TEST BANK for Physics of Everyday Phenomena 10th Edition by Thomas Griffith, Juliet Brosing

TEST BANK for Physics of Everyday Phenomena 10th Edition by

Thomas Griffith, Juliet Brosing TABLE OF CONTENTS CHAPTER 1: Physics, the Fundamental Science CHAPTER 2: Describing Motion CHAPTER 3: Falling Objects and Projectile Motion CHAPTER 4: Newton's Laws: Explaining Motion CHAPTER 5: Circular Motion, the Planets, and Gravity CHAPTER 6: Energy and Oscillations CHAPTER 7: Momentum CHAPTER 8: Rotational Motion of Solid Objects CHAPTER 9: The Behavior of Fluids CHAPTER 10: Temperature and Heat CHAPTER 11: Heat Engines and the Second Law of Thermodynamics CHAPTER 12: Electrostatic Phenomena CHAPTER 13: Electric Circuits CHAPTER 14: Magnets and Electromagnetism CHAPTER 15: Making Waves CHAPTER 16: Light Waves and Color CHAPTER 17: Light and Image Formation

CHAPTER 18: The Structure of the Atom CHAPTER 19: The Nucleus and Nuclear Energy CHAPTER 20: Relativity CHAPTER 21: Looking Deeper into Everyday Phenomena

Chapter 1: Physics, the Fundamental Science2) Describing Motion MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) People sometimes have difficulty distinguishing between scientific explanations of common events and other kinds of explanation (superstition, prejudice, magic, etc.). Which of the following best helps to identify a scientific explanation?

A) The explanation goes against the results of public opinion polls.

B) The explanation changes according to the social status of the observer.

C) We can test the explanation by comparing its predictions to measurement results.

D) The explanation relies on local folklore.

2)

The main reason that physics is perceived to be difficult is because people think that

A) all of its concepts seem incompatible with our everyday experience.

B) it frequently changes its explanations of common occurrences.

C) the laws of physicsare often shown to be wrong.

D) math is required tounderstand its ideas.

3)

The metric system of units is based on which number?

A) 2 B) 8 C) 10 D) 16

4)

Which of the following is a correct metric unit for volume?

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A) Smidgens B) Drops C) Microns D) Liters

5) A new system of units is invented where the basic unit of length is the "dak." The "dak" is defined as equal to 2 inches, and there are 2.54 centimeters in an inch. How many "daks" are there in a centimeter?

A) 4 B) 0.197 C) 2 D) 0.254

6) Suppose that, as it evaporates in the upper atmosphere, a raindrop's diameter changes from one millimeter to one micrometer. Its diameter has decreased by a factor of

A) 10, i.e., it is one tenth of the initial size.

B) 100, i.e., it is one hundredth of the initial size.

C) 1,000 (or, 103), i.e., it is one thousandth of the initial size.

D) 1,000,000 (or, 106), i.e., it is one millionth of the initial size.

7) Your new weed-cutter requires, as fuel, a gas-to-oil mixture of 20-to-1 (20 parts of gas mixed with one part of oil). You have 1/2 of a gallon of gas. How much oil, in gallons, should you add to make it all into fuel for the weed-cutter?

A) 2 B) 1/2 C) 1/20 D) 1/40

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8) Students often fail to include units with their answers. Science teachers say that units are important. In which one of the following situations would you insist that units be included?

A) Your brother asks if you would like a large soda for lunch.

B) A friend offers you two per mile to help pay for gas on a trip.

C) Your manager says you can take a break when the project you are working on is halfway finished.

D) A police officer says you did not stop at a red light.

9)

In which of these relations will S double if T is doubled?

A) S = 10T B) T = 1/S C) T = S*S D) S = 1/T

10)

Physics is considered the "Fundamental Science" because

A) if a person understands physics, he or she does not need to know anything about other sciences.

B) physics offers theonly exact explanations of how things work; other sciences only provideapproximate answers.

C) it makes the most use of mathematics.

D) the ideas andconcepts of physics are an important part of the foundation of othersciences.

11)

The development of physics concepts depends heavily on measurements because

A) measurements areneeded to prove ideas true or false.

B) withoutmeasurements, we would not know what to explain with physics.

C) measurementsinvolve mathematics.

D) physicists like numbers more than words.

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12)

The study of everyday phenomena allows us to

A) develop an understanding of the concepts used to describe more abstract concepts.

B) develop an appreciation of the physical universe around us.

C) develop our intuition and adjust our "common sense" to understand these phenomena.

D) All of these choices are correct

13) A certain parcel of real estate is sold for 7.0 Mega dollars. What is the correct scientific notation for this selling price?

A) 7.0 ×106 dollars B) 7 ×106 dollars C) 70 ×105 dollars D) 10 ×107 dollars

14) If a car travels at a constant speed, the distance the car travels in a certain time can be found using the relation d = st where d represents distance, s speed, and t time. This relationship can be expressed in words as

A) distance equalsspeed minus time.

B) multiply speed andtime to obtain the distance traveled.

C) distance equalsspeed divided by time.

D) speed is thereciprocal of time and the inverse of distance.

15) If 2 people can knit a total of 12 socks per hour, how many socks can five people knit in an 8 hour work day?

A) 200 B) 240 C) 120 D) 36

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16) One inch is defined as 2.54 centimeters. The correct expression for a one-inch length, expressed in meters, is A) 2.54 × 102 meters.

B) 2.54 × 101 meters.

C) 2.54 × 10-2 meters.

D) 2.54 × 10-1 meters.

17) It's well known that lightning strikes tall objects more frequently than short objects.

Which of the following explanations of this phenomenon could be checked for validity?

A) Tall objects always contain more structural steel than short objects.

B) Tall objects are always pointed at the top.

C) Short objects do not attract lightning because they do not conduct electricity.

D) All of these choices could be checked for validity.

18) Suppose a theory is used to make a prediction. A measurement is carried out to test the prediction. The measurement is found to have a value far larger than the prediction. This means

A) the theory must be completely incorrect and must be rejected entirely.

B) nothing becausetheories are not facts; theories often make incorrect predictions but are stillregarded as true by scientists.

C) the measurement must be incorrect; theories by definition cannot be incorrect.

D) the theory mighthave correct elements but must be modified to account for some unforeseeninfluences.

19)

By expressing relationships between quantities using mathematics, we can

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A) describe the relationships more exactly; words cannot possibly describe a relationship.

B) avoid needing tobe concerned with units.

C) make ourstatements more compact and make manipulations easier.

D) make understanding our ideas more comfortable for everyone, including nonscientists.

20)

In order to gain a more scientific worldview, the student is encouraged to

A) perform simple experiments at home.

B) perform experiments, but only in the laboratory.

C) refrain from experiments; they are all too complicated.

D) consult the oldest books available.

21)

Which of the following is not a major subfield of physics?

A) electricity and magnetism B) thermodynamics C) statistics D) optics

22) A person claims that he can start fires by using his mental powers. If we start with the hypothesis that his claim is true, we can

A) put him in a room with just a newspaper and watch him start a fire.

B) do nothing; thisis not a testable hypothesis.

C) make him explain how he starts fires with his mind.

D) watch a video ofhim starting a fire with his mind.

23)

The study of rainbows would fall under what subfield of physics?

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A) mechanics B) thermodynamics C) optics D) electricity and magnetism E) atomic physics

24)

The key distinction between explanations provided by science and religion is

A) truth.

B) simplicity.

C) beauty.

D) testability.

25)

The principal advantage of metric units over English units is that

A) metric units areof more convenient size.

B) conversions between metric units are easier.

C) metric units are more familiar.

D) there are fewer metric units to remember than English units.

26) Suppose you are told that the force on a body (F) is given by the product of its mass (m) and the acceleration of the body (a). Which of the following mathematical equations is the correct expression of this relationship?

A) F = m/a B) F = m + a C) F = a/m D) F = m × a E) F = 1/(m × a)

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27) At night you get in your car to drive to the store. The car starts but none of the lights work. Which of the following activities would NOT be considered part of the scientific method?

A) Slam the hood down hard.

B) Check the fuse in the light circuit.

C) Check the wiring from the battery to the lights.

D) Replace the light bulbs with new bulbs.

28) A scout steps off a distance of 120 steps. If each step is 70 cm, what is the distance in meters?

A) 8.4 m B) 84 m C) 840 m D) 8400 m

29)

The metric unit most comparable in size to the English inch unit is the

A) micrometer.

B) millimeter.

C) centimeter.

D) meter.

E) kilometer.

30)

Which of the following units is NOT appropriate for measuring volume?

A) cup B) liter C) centimeter D) pint E) milliliter

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31) If you start with the number 3.0 and move the decimal point one unit to the left, you wind up with 0.30. If you move the decimal point a total of five units to the left, the result is the same as that of dividing the original number by

A) 10.

B) 103.

C) 104.

D) 105.

32) The liter is a metric unit of volume. The U.S. customary unit of volume most nearly equal to the liter is the

A) quart.

B) cup.

C) teaspoon.

D) gallon.

33)

Which of these is not important to the development of scientific explanations?

A) measurement B) communication C) debate D) All of these choices are important.

34) Two different hypotheses are developed to explain why balls bounce. Experiments using basketballs show each hypothesis works equally well. To decide which one is more likely to be correct, you could

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A) find out which one was developed by the more educated person.

B) use the one that involved more mathematics.

C) ask threephysicists and choose the hypothesis that got the most votes.

D) try an experimentusing baseballs.

35) When a scientist wants to strengthen a theory, she can make predictions of measurable events. The theory becomes stronger when

A) the theory is voted upon in a democratic process.

B) she and otherscientists observe and measure the events, and they find that the events agreewith the prediction.

C) her supervisorgives the prediction government funding.

D) the measurement process goes against the prediction, thereby proving the theory valid.

36) In order to avoid cooking disasters, a numerical recipe has an advantage over purely verbal directions. That is, verbal directions can become longwinded and put the cook at risk of distraction. On the other hand, a numerical recipe like "two parts water to one part rice"

A) is easily set to music.

B) is useful for any amount of rice, because it is a ratio.

C) is also useful in the periodic table of elements.

D) obeys Newton's three laws of motion.

37) When trying to make sense of the universe, it is useful to study everyday physics of things you see in your hometown, even in your own kitchen, because

A) no one knows anyof the physical principles that govern the universe outside our planet,Earth.

B) we expect thesame laws govern physics in your hometown and everywhere else in theuniverse.

C) only astrology governs the planets.

D) when you finish,you can eat the experiment.

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38)

The numerical factor 109 corresponds to what quantity?

A) a million B) a billion C) a millionth D) a trillionth

39)

Which of the following objects can you use to roughly visualize a length of 1 meter?

A) the diameter of a human hair B) the length of an ant on the sidewalk C) the length of a 2 liter bottle of soda pop D) the height of a kitchen counter E) the length of a football field

40) Scientists generally agree that global warming has resulted mostly from an increase in what substance in the atmosphere?

A) nitrogen B) carbon monoxide C) carbon dioxide D) sulphur dioxide

41) The increase in the average atmospheric temperature for the entire planet Earth over the last few centuries can be explained by the

A) greenhouse effect.

B) increase in size of gaps in the ionosphere.

C) melting of the polar icecaps.

D) change in the average salt levels in the oceans.

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42)

Which of the following is not considered to be a fossil fuel?

A) coal B) uranium C) natural gas D) crude oil

43) Historical measurements of the average surface temperature of the Earth have shown an accelerating pace since

A) 1850.

B) 1900.

C) 1940.

D) 1980.

44)

Applications of semiconductor technology include

A) more powerful antibiotics.

B) photovoltaic cells.

C) efficient car batteries.

D) fossil fuel burning electric generators.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

45) The metric unit of length closest to our English mile unit is the .

46) The distance around the earth at the equator is about 40,000 kilometers. This can be written as mega meters.

47)

The subfield of

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48) Four cars are required to take a group of 16 students on a trip. If there were 36 students to transport cars would be needed.

49) After making observations and finding some rules as to how nature works, a scientist proceeds to make a(n) to explain the observed rules.

50) To prepare two servings of hot cereal, a cook mixes 1/3 cup of ground cereal with one cup of hot water. To prepare six servings will require cup(s) of cereal and cup(s) of hot water.

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Answer Key Test name: Chap 01_10e 1) C 2) D 3) C 4) D 5) B 6) C 7) D 8) B 9) A 10) D 11) A 12) D 13) A 14) B 15) B 16) C 17) D 18) D 19) C 20) A 21) C 22) A 23) C 24) D 25) B 26) D Version 1

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27) A 28) B 29) C 30) C 31) D 32) A 33) D 34) D 35) B 36) B 37) B 38) B 39) D 40) C 41) A 42) B 43) D 44) B 45) kilometer 46) 40 47) mechanics 48) 9 49) hypothesis 50) [1, 3]

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Chapter 2: Falling Objects and Projectile Motion MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) An auto, starting from rest, undergoes constant acceleration and covers a distance of 1250 meters. The final speed of the auto is 50 meters/sec. How long does it take the car to cover the 1250 meters?

A) 30 s B) 50 s C) 0.05 s D) 72,000 s

2)

A car traveling at constant speed

A) does not turn.

B) travels more distance in a second the longer the car travels.

C) can change direction.

D) cannot begoing uphill.

3) An auto moves 10 meters in the first second of travel, 15 more meters in the next second, and 20 more meters during the third second. The acceleration of the auto is A) 3.33 m/s2.

B) 9.8 m/s2.

C) 30 m/s2.

D) 5 m/s2.

E) zero m/s2.

4)

A quantity that is a measure of how the velocity of a body changes with time is

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A) distance.

B) speed.

C) acceleration.

D) time.

5) The following quantities relate to the rate of change of position. Which pair will always have the same magnitude?

A) average speed and average velocity B) average speed and instantaneous speed C) average velocity and instantaneous velocity D) instantaneous speed and instantaneous velocity

6)

The acceleration of a body cannot be zero at a point where

A) the instantaneous velocity is zero.

B) the instantaneous velocity is positive but decreasing.

C) the average velocity is positive.

D) None of these choices are correct.

7) A student releases a ball from rest on an inclined plane and measures that it travels a distance of 0.8 m in a time of 4.0 s. The average speed of the ball is

A) 3.2 m/s.

B) 1.0 m/s.

C) 0.2 m/s.

D) 2.0 m/s.

8) A student releases a ball from rest on an inclined plane and measures that it travels a distance of 0.5 m in a time of 2.0 s. The acceleration of the ball is

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A) 0.125 m/s2.

B) 0.25 m/s2.

C) 0.5 m/s2.

D) 1.0 m/s2.

9) A car travels a distance of 100 km. For the first 30 minutes it is driven at a constant speed of 80 km/hr. The motor begins to vibrate and the driver reduces the speed to 40 km/hr for the rest of the trip. The average speed for the entire trip is

A) 60.0 km/hr.

B) 53.3 km/hr.

C) 50.0 km/hr.

D) 47.5 km/hr.

E) 40.0 km/hr.

10) Initially you are driving at 55 mi/hr. If you come to rest in 7.5 s while traveling 450 ft, what is your average speed while stopping? (There are 5280 ft in one mi.)

A) 55 mi/hr B) 0.016 ft/s C) 120 ft/s D) 60 ft/s

11)

If your average speed for a 6 hr trip is 60 mi/hr, the distance traveled is A) 10 mi.

B) 60 mi.

C) 120 mi.

D) 360 mi.

12) You travel 2640 feet in thirty seconds while in a 65 mi/hr zone. (There are 5280 ft in one mi.) Your average speed is Version 1

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A) larger than the speed limit.

B) exactly the speed limit.

C) less than the speed limit.

13) In a speedometer test zone on a highway, you drive 4 miles in 5 minutes. During the test, your speedometer reading is 45 mi/hr. Your speedometer reading is

A) lower than your actual speed.

B) equal to your actual speed.

C) higher than your actual speed.

14) Your car can accelerate at 8.0 m/s2, and there are 1609 m in one mile. So you can go from zero to 60 mi/hr in about

A) 3.35 s.

B) 2.74 s.

C) 1.34 s.

D) 0.37 s.

15)

In order to go from rest to 50 m/s in 10 s, a jet must be able to accelerate at A) 2 m/s2.

B) 5 m/s2.

C) 20 m/s2.

D) 50 m/s2.

16) If the braking distance for your car at a certain speed is 200 ft and, after reacting to a situation, you have managed to stop your car in 5.0 s, then the magnitude of the acceleration was

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A) 16 ft/s2.

B) 25 ft/s2.

C) 32 ft/s2.

D) 50 ft/s2.

17) A student plots data for the velocity of a body versus the time on a graph. The area under the curve on the graph may be identified as

A) acceleration.

B) averagevelocity.

C) averagespeed.

D) distance.

18) Suppose a graph of distance traveled by a body versus time is constructed. The slope of the graph at any point may be identified with

A) instantaneousacceleration.

B) instantaneousvelocity.

C) average acceleration.

D) average speed.

19)

A policeman walks on his beat back and forth. His average speed is determined from

A) his velocitydivided by the time.

B) time divided byhow far he ends up from the starting point.

C) his totaldistance covered divided by the time.

D) time divided byhis total distance covered.

20) A car is driven between two nearby towns at an average speed of 50 miles/hour. The magnitude of the average velocity of the car

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A) will always be the same as the average speed.

B) will always be less than the average speed.

C) will be the sameas or greater than the average speed.

D) will be the sameas or less than the average speed.

E) will always be greater than the average speed.

21) A car starts from rest and reaches 20 m/s in 5 seconds. The average acceleration of the car is A) zero m/s2.

B) 1.0 m/s2.

C) 2.0 m/s2.

D) 4.0 m/s2.

E) 10.0 m/s2.

22)

Which of the following is not an appropriate unit for measuring acceleration?

A) miles/hr/s B) ft/s2 C) m/s D) km/min/s E) m/min2

23) A car rolls down an incline starting from rest. A graph of position versus time is made for this motion. One can get the

A) distance traveled from the slope of the graph.

B) instantaneous velocity from the slope of the graph.

C) acceleration from the slope of the graph.

D) velocity from the area under the graph.

E) acceleration from the area under the graph.

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24) A car is traveling at the velocity of 20 m/s on a flat road when it reaches the bottom of a hill. It coasts up the hill, coming to rest in 8 seconds. The average acceleration of the car while on the hill is A) 10 m/s2.

B) 2.5 m/s2.

C) 0 m/s2.

D) -2.5 m/s2.

E) -10 m/s2.

25)

Which of the following quantities relating to motion is not a vector?

A) speed B) velocity C) acceleration D) All of these choices are correct.

26) Two velocity vectors are added: one of magnitude 2.0 m/s and one of magnitude 5.0 m/s.

Not knowing the respective directions, we can say that the magnitude of the sum of the vectors will be A) 7.0 m/s.

B) between 7.0 m/s and 3.0 m/s.

C) between 7.0 m/s and 2.0 m/s.

D) less than 2.0m/s.

E) 3.0 m/s.

27) The velocity of a body is graphed as a function of time. The slope of the graph at any point may be identified with

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A) instantaneous velocity.

B) average velocity.

C) instantaneous speed.

D) instantaneous acceleration.

E) average acceleration.

28)

A quantity that is a measure of how the distance traveled changes with time is

A) speed.

B) force.

C) acceleration.

D) momentum.

29) A body travels at an initial speed of 2.4 m/s. Given a constant acceleration of 0.5 m/s2, what is the speed of the body at time 18 seconds later?

A) 2.4 m/s B) 3.6 m/s C) 4.5 m/s D) 9.0 m/s E) 11.4 m/s

30) A car is decelerating at the rate of 2 km/s2. If its initial speed is 66 km/s, how long will it take the car to come to a complete stop?

A) 3.3 s B) 132 s C) 33 s D) 330 s

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31) For the first hour a car is driven at a constant speed of 90 km/hr. The motor begins to vibrate and the driver reduces the speed to 45 km/hr for another 2 hours. The average speed for the entire trip is

A) 90.0 km/hr.

B) 25.5 km/hr.

C) 60.0 km/hr.

D) 67.5 km/hr.

E) 45.0 km/hr.

32) A car moving initially at 30 m/s comes gradually to a stop in 900 m. What was the acceleration of the car?

A) -0.5 m/s2 B) -5 m/s2 C) -10 m/s2 D) -20 m/s2

33)

An object moving at 30 m/s has an acceleration of -2.0 m/s/hr. Its speed

A) increases veryquickly.

B) increases veryslowly.

C) decreases veryslowly.

D) decreases veryquickly.

34) A sprinter moving at 10 m/s slows down at a rate of 2 m/s2. How fast is the runner moving after 3 seconds?

A) 0 m/s B) 4 m/s C) 7 m/s D) 16 m/s

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35) A car driver takes Turn 1 at Daytona International Speedway at a steady 120 mph all the way through the turn. The radius of this turn is 1000 feet. Which statement is true?

A) Its velocity is constant because its speed is constant.

B) Its speed is constant so its acceleration is zero.

C) Change of direction at constant speed means a change in velocity.

D) Its velocity changes only if its speed decreases.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

36) Suppose a body sliding up a ramp is decelerating at a constant rate. Its speed will by the same amount each second.

37) A car starts from rest and after 10 seconds is traveling at 30 m/s. Assuming that it continues to accelerate at the same rate it will take another seconds to reach 60 m/s.

38) A car accelerates uniformly. It starts from rest and reaches 36 m/s after 9.0 seconds.

During the 9.0 seconds it has traveled m.

39) The tip of the second hand of a clock moves in a circle of 20 cm circumference. In one minute the hand makes a complete revolution. Its average velocity over that time is cm/s.

40) A speed of 150 km/hr is equivalent to (Round your answer to the nearest whole number.)

41)

mph. (There are 1.609 km in a mile.)

From a graph of speed versus time for a body sliding down a ramp, one can get the from the slope of the curve.

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42)

If you are traveling 80 mph, how many hours does it take you to go 160 miles?

SECTION BREAK. Answer all the part questions.

43) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

43.1) An object's distance traveled as a function of time is shown in the graph. The graph shows

A) an objectexperiencing an acceleration.

B) an object withincreasing speed.

C) an object turningin a circle.

D) an object moving forward.

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44) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

44.1)

Refer to the graph of velocity versus time. The object moves forward

A) in region A. B) in region B. C) in regions A and C. D) The object always moves forward.

E) The object never moves forward.

44.2) Refer to the graph of velocity versus time. The acceleration of the object is equal to zero

A) in region A. B) in region B. C) in region C. D) in regions A and C. E) The acceleration is never equal to zero.

44.3) Refer to the graph of velocity versus time. The magnitude of the acceleration of the object is largest Version 1

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A) in region A. B) in region B. C) in region C. D) The object does not accelerate.

45) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

45.1) Refer to the graph of distance versus time. The velocity of this object at the start of the motion is

A) positive.

B) zero (it is notmoving).

C) negative.

D) It is not possible to tell from the graph.

45.2) Refer to the graph of distance versus time. For the entire motion, the average velocity is

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A) positive.

B) zero (it is notmoving).

C) negative.

D) It is not possible to tell from the graph.

45.3)

Refer to the graph of distance versus time. The speed of the object is largest

A) in region A. B) in region B. C) in region C. D) in region D. E) in region E.

46) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

46.1) Refer to diagram of billiard balls F, K, M, and T. Each arrow represents the velocity of the ball. If billiard ball M is traveling straight upward at 2.5 m/sec, then

A) billiard ball Mmust be faster than T. B) billiard ball Fis the slowest of the four.

C) billiard ball Khas the same velocity as M. D) nothing about their speeds can be said, because they are all moving in different directions.

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47) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

47.1)

Refer to the speedometer in Figure 2.3. The speedometer reading 75 mph is

A) approximately 2 kilometers per minute.

B) exactly 1 mile per minute.

C) 200 meters per second.

D) the only speed atwhich mph and km/h are equal.

48) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

Refer to the diagram of Racetrack X.

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48.1) This special racetrack is all curve and no straightaway. If a driver takes her car around this track counterclockwise and at constant speed, then greater acceleration will occur at any place the turning radius is

A) larger.

B) smaller.

C) inward.

D) outward.

48.2) Refer to the diagram of Racetrack X. It is acceleration on this track.

for a racer to have uniform

A) impossible;anywhere B) impossible; atsome places C) possible;everywhere D) guaranteed; at some places

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Answer Key Test name: Chap 02_10e 1) B 2) C 3) D 4) C 5) D 6) B 7) C 8) B 9) C 10) D 11) D 12) C 13) A 14) A 15) B 16) A 17) D 18) B 19) C 20) D 21) D 22) C 23) B 24) D 25) A 26) B Version 1

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27) D 28) A 29) E 30) C 31) C 32) A 33) C 34) B 35) C 36) decrease 37) 10 38) 162 39) 0 40) 93 41) instantaneous acceleration 42) 2 43) Section Break 43.1) D 44) Section Break 44.1) A 44.2) E 44.3) B 45) Section Break 45.1) B 45.2) C 45.3) D 46) Section Break 46.1) A 47) Section Break 47.1) A Version 1

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48) Section Break 48.1) B 48.2) A

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Chapter 3: Newton's Laws: Explaining Motion MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) Neglecting friction, if a Cadillac and Volkswagen start rolling down a hill together, the heavier Cadillac will get to the bottom

A) before the Volkswagen.

B) after the Volkswagen.

C) at the same time as the Volkswagen.

2) A bullet is fired straight down from a hovering helicopter. If we neglect air friction, then the speed of the bullet

A) increases at about 10 m/s each second.

B) is a constant.

C) is zero.

D) decreases at about 10 ft/s during the flight.

3) Suppose you throw a ball vertically downward with a speed of 10 m/s. Neglecting air friction, what would be the approximate speed of the ball one second later?

A) -10 m/s2 B) 10 m/s2 C) 15 m/s D) 20 m/s E) 30 m/s

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4) Which of the curves in the figure best shows the speed of an object falling from rest without air friction?

A) A B) B C) C

5) If you drop a ball in the absence of air resistance, it accelerates downward at approximately 10 m/s2. If instead you throw the ball upward, then its downward acceleration after release is approximately A) less than 10 m/s2.

B) equal to 10 m/s2.

C) greater than 10 m/s2.

6) A person standing at the edge of a cliff throws one rock straight up and another rock straight down at the same initial speed. The rock that was thrown has less speed at impact.

A) upward B) downward C) each rock has the same speed just before impact

7)

You toss a ball straight up in the air. At the highest point, the ball's

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A) velocity and acceleration are zero.

B) acceleration is zero but not its velocity.

C) velocity is zeroand the acceleration is downward.

D) velocity is zeroand the acceleration is upward.

8) (Ignore air resistance for this problem.) Two identical balls are thrown simultaneously from the top of a very tall cliff. Ball A is thrown downward with an initial velocity of 6 m/s, while ball B is thrown straight upward with an initial velocity of 10 m/s. After one second has elapsed, the

A) acceleration of ball A is upward.

B) velocity of ball A is 10 m/sec2.

C) acceleration of ball A is greater than that of ball B. D) velocity of ball B is approximately zero.

E) acceleration of both balls is zero.

9) A football is thrown upward at some angle above the horizontal. If we neglect air friction, then we can conclude that the acceleration vector of the football is

A) opposite to the velocity vector.

B) zero.

C) along the direction of motion.

D) down.

10) An iron robot falls from rest at a great height. Neglecting air resistance, what is its approximate speed after it has fallen for 3.5 seconds?

A) 10 m/s B) 10 m/s2 C) 20 m/s D) 35 m/s

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11) An iron robot falls from rest at a great height. Neglecting air resistance, approximately what distance has it fallen in the first 4 seconds?

A) 40 m B) 80 m C) 10 m D) 160 m

12) The acceleration due to the Earth's gravity, in English units, is 32 ft/s2. In the absence of air friction, a ball is dropped from rest. Its speed on striking the ground is exactly 60 miles/hr.

For what time interval was the ball falling? (There are 5280 feet in one mile.)

A) 5 s B) 6.1 s C) 4.125 s D) 2.75 s

13) The acceleration due to the Earth's gravity, in English units, is 32 ft/s2. In the absence of air friction, a ball is dropped from rest. Its speed on striking the ground is exactly 132 ft/s. From what height was the ball dropped?

A) 165 ft B) 272 ft C) 132 ft D) 421 ft

14) In a laboratory on Earth, all the air is pumped from a large tube. A feather and a steel ball are simultaneously released from rest inside the tube. What happens next?

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A) Both objects float weightless inside the tube.

B) The steel ball falls and hits the bottom before the feather.

C) The feather falls and hits the bottom before the steel ball.

D) Both objects fall and hit the bottom at the same time.

15) In order to find the depth of a well, you drop a stone into it and time its fall. It hits the water after falling for 3 s. The depth of the well is about

A) 30 m.

B) 45 m.

C) 90 m.

D) 15 m.

16) A stone is thrown upward from a bridge at a speed of 10 m/s. It narrowly misses the bridge on the way back down and hits the water at 30 m/s. The bridge is about

A) 3 m high.

B) 20 m high.

C) 50 m high.

D) 40 m high.

17) A 10 kg object dropped from a certain window strikes the ground in 4.0 s. Neglecting air resistance, a 5 kg object dropped from the same window strikes the ground in A) 1.0 s.

B) 2.0 s.

C) 4.0 s.

D) 8.0 s.

18) An object is thrown upward at 5.0 m/s, and experiences only the force of gravity once thrown. One second later the object is

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A) rising at about 5 m/s.

B) rising at about 2 m/s.

C) neither rising nor falling.

D) falling at about 5 m/s.

19) A rifle bullet is fired horizontally at the same instant another bullet is allowed to drop from rest at the same height. Which bullet strikes the earth first?

A) the bullet from the rifle B) the bullet allowed to drop C) both strike at the same instant

20) A ball is thrown straight up. It reaches its highest point and then falls back. Which of the following is the correct statement?

A) Throughout its motion, the ball's velocity is zero.

B) At the highest point in its motion, the ball's acceleration is zero.

C) At the highest point in its motion, the ball's velocity is zero.

D) Throughout its motion, the ball's acceleration is zero.

E) At the highest point in its motion, the ball's velocity and acceleration are zero.

21) A body released from rest falls with an acceleration of about 10 m/s2. If the same body is thrown upward at an angle, and air resistance is negligible, its acceleration after release will be approximately A) downward and less than 10 m/s2.

B) downward and equal to 10 m/s2.

C) downward and greater than 10 m/s2.

D) upward and equal to 10 m/s2.

E) upward and greater than 10 m/s2.

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22)

The acceleration of a body is given by the slope of a graph plotting

A) distancetravelled versus time.

B) time versus velocity.

C) velocity versusdistance travelled.

D) velocity versustime.

E) time versusdistance travelled.

23) If air resistance can be ignored, which of the following graphs will be a straight line for a falling object?

A) distance travelled versus time B) distance travelled versus velocity C) time versus distance travelled D) velocity versus time E) velocity versus distance travelled

24) A ball is allowed to drop from rest. If the upward direction is positive, then after 2 seconds its velocity will be approximately

A) -20 m/s.

B) -10 m/s.

C) 10 m/s.

D) 20 m/s.

25)

After 1 second, a ball dropped from rest will have fallen about

A) 1.0 m.

B) 2.5 m.

C) 5.0 m.

D) 10 m.

E) 20 m.

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26) A ball is thrown straight up with an initial velocity of 10 m/s. After 3 seconds its velocity will be approximately

A) -20 m/s.

B) -30 m/s.

C) 0 m/s.

D) 30 m/s.

E) 20 m/s.

27) A ball is projected upward with an initial velocity of 10 m/s. It will reach its maximum height in approximately

A) 1 s.

B) 1.5 s.

C) 2 s.

D) 2.5 s.

E) 3 s.

28) A ball thrown upward reaches its maximum height and then falls back. If air resistance is negligible, its acceleration is

A) less on the way up than on the way down.

B) less on the way down than on the way up.

C) the same up and down but zero at the top.

D) the same at all points in the motion.

29) Ball A is thrown upward with a velocity of 20 m/s. Two seconds later ball B is thrown upward with a velocity of 10 m/s. Which ball is first to return to the thrower's hand?

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A) A will arrive first.

B) A and B will arrive at the same time.

C) B will arrive first.

30) A bullet is fired horizontally at a target 40 m away. The velocity of the bullet as it leaves the gun is 100 m/s. How much, approximately, will the bullet drop on its way to the target?

A) 0.05 m B) 0.4 m C) 0.8 m D) 1.0 m E) 2.0 m

31) fall?

During the first 5 seconds after a ball is dropped from rest, approximately how far will it

A) 25 m B) 50 m C) 125 m D) 250 m E) 500 m

32) A 10 pound iron ball and a 2 pound iron ball are dropped simultaneously from a height of 100 meters. Neglecting air resistance, which ball will reach the ground first?

A) the 10 lb ball B) the 2 lb ball C) They will reach the ground at the same time.

33) A man standing on a bridge throws a stone horizontally with a speed of 20 m/s. The stone hits the water below 4 s later. The bridge is approximately

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A) 40 m high.

B) 60 m high.

C) 80 m high.

D) 20 m high.

34)

The motion of a falling object is commonly investigated with the aid of a

A) stethoscope.

B) microscope.

C) kaleidoscope.

D) stroboscope.

35) A ball rolls off a shelf and hits the floor below 0.25 second later. To find the speed of the ball as it left the shelf, we would need

A) the distancemeasured along the floor to the point of impact.

B) to repeat the experiment.

C) the height of the table.

D) the weight of the ball.

36) Assuming g = 10 m/s2 and that air resistance is negligible, in 1/2 second a ball dropped from rest will fall

A) 0.3 m.

B) 0.8 m.

C) 1.0 m.

D) 1.25 m.

E) 2.25 m.

37) One day while measuring acceleration with his pulse as a timing source, Galileo became so excited that his pulse rate increased. His results for acceleration that day were probably

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A) higher thanusual.

B) lower thanusual.

C) more accurate than usual.

D) unchanged.

38)

A ball is thrown across the street. During its flight, the ball's speed is lowest at

A) the beginning of its flight.

B) the end of itsflight.

C) the highest point of its flight.

D) The speed is constant throughout the flight

39)

Which of the following does not move like a projectile?

A) a monkey jumping from a tree B) the seeds at a watermelon seed spitting contest C) an airplane flying at a constant altitude D) a rock kicked up by a truck wheel

40) The acceleration due to gravity near the surface of the Moon is about one-sixth of the value near the Earth's surface. If a rock were dropped from equal heights on the Moon and Earth, the time it would take the rock from the Moon to hit the ground would be

A) six times longer than on Earth.

B) the square root of six times longer than on Earth.

C) the same time as on Earth.

D) the square root of six times shorter than on Earth.

E) six times shorter than on Earth.

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41) The acceleration due to gravity near the surface of Mars is about one-third of the value near the Earth's surface. If a rock fell from rest for the same amount of time on Mars and Earth, the final speed of the rock would be

A) three timesfaster than on Earth.

B) the square rootof three times faster than on Earth.

C) the same speed as on Earth.

D) the square rootof three times slower than on Earth.

E) three timesslower than on Earth.

42)

Which of these graphs would be correct for the speed of a ball thrown upward?

A) A B) B C) C D) D

43) Two people stand on different floors of an outdoor stairway. One is 6 m above the ground and the other is 12 m above the ground. The person on the lower floor throws a ball upward with a speed of 15 m/s and the other person just drops hers. Ignoring air resistance, which ball hits the ground at a higher speed?

A) the one thrown upward B) the one that is dropped C) They both hit the ground with the same speed.

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44) A ball is thrown at an angle above the horizontal. The horizontal speed of the ball is 20 m/s and the ball covers a distance of 10 m. The maximum height of the arc through which the ball travels is approximately

A) 1.2 m.

B) 5 m.

C) 10 m.

D) 0.31 m

45) Two projectiles are launched 50° above horizontal but with different initial speeds.

Which of the following must be true while the projectiles are in the air? (Ignore air resistance.)

A) The projectiles will reach the same maximum height.

B) The horizontal speeds of both projectiles are the same.

C) The horizontal accelerations of both projectiles are the same: zero.

D) The one with larger initial speed will experience a larger vertical acceleration.

46) Which of the three curves show the speed of an object that is beginning to experience significant air resistance?

A) Object U B) Object G C) Object K

47) To get a clean "swish"—nothing but net—on the basketball floor, you must shoot the ball so that its velocity vector is at least above horizontal when it gets to the hoop.

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A) 45° B) 58° C) 32° D) 30°

48) For identical cannons and identical projectiles and identical initial speeds, but different pointing angles, the maximum distance for its projectile is attained for the cannon which launches at

A) 32° above horizontal.

B) 45° above horizontal.

C) either 32° or 58° above horizontal.

D) zero degrees—a flat trajectory.

49) A baseball pitcher throws a fastball at 98 mph. He also has a slower "changeup" pitch, 75 mph, which he throws identically, same windup and same release angle from shoulder height.

Which pitch gets to home plate with a flatter trajectory—i.e., velocity vector closer to horizontal?

A) the fastball B) the changeup C) They each have same trajectory, since the distance to home plate is the same.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

50) During batting practice, two baseballs have the same speed when leaving the bat of Babe Ruth. One ball goes over the outfield fence for a home run, and the other can be caught by an infielder. The difference between the two swings is that the home run ball starts out at an angle 45°.

51) A body whose velocity increases by a constant amount each second is exhibiting motion for which the is constant.

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52) For a bullet fired horizontally, its value until it is stopped.

velocity will retain a constant non-zero

53) The time of flight of a projectile, fired horizontally over level ground, is independent of its horizontal .

54) A football is kicked at an angle, giving it a horizontal velocity of 25 m/s. At the highest point in its path, the football will have a velocity of m/s and a horizontal acceleration 2 of m/s .

55) A gravity.

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Answer Key Test name: Chap 03_10e 1) C 2) A 3) D 4) B 5) B 6) C 7) C 8) D 9) D 10) D 11) B 12) D 13) B 14) D 15) B 16) D 17) C 18) D 19) C 20) C 21) B 22) D 23) D 24) A 25) C 26) A Version 1

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27) A 28) D 29) B 30) C 31) C 32) C 33) C 34) D 35) A 36) D 37) A 38) C 39) C 40) B 41) E 42) A 43) A 44) D 45) C 46) B 47) C 48) B 49) A 50) closer 51) acceleration 52) horizontal 53) velocity 54) [25, zero] 55) projectile

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Chapter 4: Newton's Laws: Explaining Motion MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) All except one of the following require the application of a net force. Which one is the exception?

A) changing an object from a state of rest to a state of motion B) changing an object's speed without changing its direction of motion C) maintaining an object in motion at a constant velocity D) maintaining an object in uniform circular motion E) changing an object's direction of motion without changing its speed

2) A common experience is to find that a steady pull is required to keep an object moving, even on a level surface, when friction is present. Analyzing this experience in light of the laws of motion, the accepted conclusion is that

A) the laws of motion do not apply where there is friction.

B) a frictional forceexactly opposes your pull and the first law applies.

C) the object isreally accelerating but it is not apparent.

D) your pull is canceled by the third law reaction force.

E) the laws of motion only apply when you start pulling or stop.

3) The starship Enterprise locks onto an alien ship (whose mass is much greater than the Enterprise's mass) with its tractor beam (think of this as a futuristic rope) and starts to pull the alien ship toward it. Neither ship has its propulsion engines running. Which ship has greater acceleration towards the other?

A) the Enterprise B) the alien ship C) They both move with equal acceleration.

D) Neither ship can move because there is no friction in outer space.

4)

The force that accelerates a car on a level road is exerted by the

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A) road on thetires.

B) gears on the axle.

C) tires on theroad.

D) engine on thegears.

5) A 10-pound sack of potatoes falls from an airplane. As the velocity of the falling sack increases, so does the air resistance on it. When the air resistance equals 10 pounds, the acceleration of the sack will be A) 100 ft/s2.

B) 9.8 m/s.

C) 9.8 m/s2.

D) zero.

A single constant 10-pound force F1 acts on a body, causing it to accelerate. Then, while 6) F1 continues to act, a second constant force F2 is applied to the body, which comes to a momentary stop. The magnitude of F2 is

A) zero.

B) a bit less than 10 pounds.

C) exactly 10 pounds.

D) larger than 10 pounds.

E) There is not enough information to tell.

7)

The frictional force, due to air resistance, acting on an object is always

A) greater than thenet force.

B) in the directionof the object's motion.

C) in the oppositedirection to the object's motion.

D) in the upward direction.

E) smaller than object's weight.

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8) An elevator is being lifted upward at a constant speed by a steel cable. All frictional forces are neglected. In this situation, forces on the elevator are such that

A) the upward forceby the cable is smaller than the downward force of gravity.

B) the upward force by the cable is equal to the downward force of gravity.

C) the upward forceby the cable is greater than the downward force of gravity.

D) None of these choices are correct (the elevator goes up because the cable is being shortened, not because an upward force is exerted on the elevator by the cable).

9) The erroneous idea that an object needs a force on it to keep moving even at constant velocity was held by

A) Aristotle.

B) Galileo.

C) Newton.

10) Two pieces of kryptonite, #1 and #2, have identical masses, but the net force applied to #1 is 400 N and to #2 is 20 N. The acceleration

A) of #1 is larger.

B) of each piece of kryptonite is the same.

C) of #2 is larger.

D) depends on the weight of each piece of kryptonite.

11) A body sliding on a table is observed to gradually slow down. The correct statement is that the body slows down because

A) no force acts on the body.

B) no net force acts on the body.

C) it is the natureof the body to slow down by itself.

D) a net force actson the body.

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12) A car rounds a curve while maintaining constant speed. Which of the statements is correct?

A) The acceleration of the car is zero.

B) No net force acts on the car.

C) The velocity of the car is zero.

D) The velocity of the car is constant.

E) A net force acts upon the car.

13) Two blocks of different mass are connected by a string. The system is accelerated across a smooth horizontal surface by a force supplied by a rubber band connected to the less massive block. The tension in the connecting string will be

A) greater than theforce pulling the leading block.

B) the same as theforce pulling the leading block.

C) less than theforce pulling the leading block.

D) zero.

14) The acceleration of gravity on the Moon's surface is about 1/6 of that on the Earth's surface. An object on the Earth is to be taken to the Moon. We can state that, compared to the Earth,

A) the object's mass and weight will be the same on the Moon.

B) the object's masswill be the same but the weight will be less on the Moon.

C) the object's masswill be less but the weight will be the same on the Moon.

D) the object's mass and weight will be less on the Moon.

15) A block, moving on a frictionless horizontal surface on Earth, requires a force if it is to be stopped. Now suppose that the same block, moving with the same speed on a frictionless horizontal surface on the Moon, where gravity is less, is to be stopped in the same time. We can say that, compared to the Earth,

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A) less force is required to stop the block on the Moon.

B) the forcerequired would be the same.

C) greater force isrequired to stop the block on the Moon.

D) the block could not be stopped.

16) A calculus book weighing 20 N rests on the floor of a classroom. In this case, the magnitude of the force exerted by the floor on the book is equal to

A) 9.8 N. B) 0 N. C) 2.04 N. D) 20 N.

17) Suppose one's hand exerts a force of 12 N upward on a book weighing 10 N. The reaction to the force of the hand on the book is a force of

A) 10 N exerted by the Earth on the book.

B) 10 N exerted by the book on the Earth.

C) 12 N exerted by the book on the hand.

D) 10 N exerted by the book on the hand.

E) 2 N exerted by the book on the hand.

18) A block of mass 3.0 kg is acted upon by a single force, producing an acceleration of 2.0 2 m/s . The force has a value of A) 6.0 N. B) 5 N. C) 3.0 N. D) 1.5 N.

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19) A 10.0 kg block on a smooth horizontal surface is acted upon by two forces: a horizontal force of 70 N acting to the left and a horizontal force of 30 N to the right. The acceleration of the block will be A) 2.3 m/s2 to the right.

B) 4.0 m/s2 to the right.

C) 10.0 m/s2 to the left.

D) 4.0 m/s2 to the left.

20) A crate is acted upon by a net force of 100 N. An acceleration of 4.0 m/s2 results. The weight of the crate is

A) 25 lb.

B) 25 N. C) 25 kg.

D) 245 N. E) 245 lb.

21) A parachutist jumping from an airplane reaches a terminal velocity when the force of air resistance is 980 N. The mass of the parachutist is

A) 220 lb.

B) 980 lb.

C) 980 kg.

D) 100 lb.

E) 100 kg.

22) An elevator of mass 500 kg is caused to accelerate upward at 3.0 m/s2 by a force in the cable. What is the force exerted by the cable?

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A) 1,500 N B) 4,900 N C) 6,400 N D) 2,900 N E) zero

23) When a net horizontal force of 250 N acts on a 50-kg cart that is free to roll on a level surface, A) the cartaccelerates at 9.8 m/s2.

B) the cartaccelerates at 5 m/s2.

C) the cartaccelerates at 12500 m/s2.

D) the cartaccelerates at 0.20 m/s2.

E) the cart does notaccelerate because it pushes back on the person with a force of 250 N.

24) A child, whose weight is 150 newtons, lifts a pumpkin from the ground with a force of 50 newtons. The force the pumpkin exerts on the child is

A) more than 50newtons.

B) 50 newtons.

C) greater than zerobut less than 50 newtons.

D) zero.

25) A certain force causes a 50 kg person to accelerate at 1.0 m/s2. The same force applied to a 75-kg person would cause

A) a greateracceleration.

B) the same acceleration.

C) a smalleracceleration.

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26) You stand on a scale to measure your weight. The reaction to the force the Earth exerts on you is

A) the force the scale exerts on you.

B) the force theEarth exerts on the scale.

C) the force you exert on the scale.

D) the force the scale exerts on the Earth.

E) the force youexert on the Earth.

27) The surface gravity of Mars is 3.7 m/s2. If a person with mass of 100 kg were parachuting on Mars, what would be the force exerted by air resistance at terminal velocity?

A) 980 N B) 490 N C) 370 N D) 100 N

28)

A dog weighs 200 N. What is his approximate weight in pounds (lb)? (1 lb = 4.45 N)

A) 200 lb.

B) 91 lb.

C) 32 lb.

D) 45 lb.

E) 20 lb.

29) The force exerted on a body by moving air is proportional to the projected area of the body. Which falling body will have the larger terminal velocity, a flying squirrel with its wing membranes extended or a grey squirrel with the same mass?

A) the flying squirrel B) the grey squirrel C) Both will have same terminal velocity.

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30) Your weight is 120 lb. Suppose you are standing on a scale in an elevator moving up with a constant speed of 4 m/s. What would be the reading on the scale?

A) 480 lb.

B) 120 lb.

C) 70 lb.

D) 30 lb.

E) 0

31) Your mass is 50 kg. Suppose you are standing on a scale in an elevator that starts moving up and increases its speed at the rate of 3 m/s every second. What would be the reading on the scale?

A) 740 N B) 640 N C) 340 N D) 150 N E) 0 N

32) Your mass is 50 kg. Suppose you are standing on a scale in an elevator that is approaching a top floor and decreasing its speed at the rate of 3 m/s every second. What would be the reading on the scale?

A) 740 N B) 640 N C) 340 N D) 150 N E) 0 N

33) Consider two blocks, one made of wood and the other of lead. They have the same dimensions but the lead is much more massive. If they are dropped and fall long enough to reach terminal velocity, which block experiences a larger force from air resistance?

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A) the lead block B) the wood block C) The force on each is equal.

D) It isn't important because air resistance can be ignored.

34) In this diagram a force acting on a block is shown by the arrow labeled F. The mass of the block is known, as is the size of the force, but the observed acceleration is larger than F/m and so another force must act on the block. In which direction (A, B, C, or D) is this force?

A) A B) B C) C D) D

35)

Three forces act on the object in the sketch. In what direction will the object move?

A) upward B) to the left C) to the left and up D) to the right E) to the right and up

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36) The acceleration due to gravity is smaller on Mars than the Earth, so the Mars rovers that explore the surface are lighter on Mars than they are on Earth. If the rovers roll across a flat plain, then the force required to accelerate the rovers is

A) less than would be required on Earth.

B) the same as would be required on Earth.

C) more than would be required on Earth.

37) A father and his young daughter are on very clean ice, so there is very little friction (the father has more mass than the daughter). The father pushes his daughter forward and she slides away at a speed of 3 m/s. The father's velocity is

A) smaller than 3m/s in the opposite direction as his daughter.

B) zero.

C) smaller than 3m/s in the same direction as his daughter.

D) 3 m/s in the same direction as his daughter.

E) 3 m/s in the opposite direction as his daughter.

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38) A shiny, spherical, metal alien jumps out of a perfectly good airplane and skydives for a few seconds. Its photographic friend snaps photos of the alien with a special camera that also captures the forces on the object.

This diagram shows a few of the snapshots, but they are out of order. Place them in order, from the instant it jumps out of the plane and begins free-fall until the time it attains terminal velocity.

Assume that the parachute has not deployed yet. If any of the diagrams depict a situation not physically possible, omit it from the ordering.

A) L, Y, J, Q B) J, Y, L, J C) L, Q, J D) Q, Y E) L, J, Q

39) A physics professor places a soda pop can on the table and asks a student to identify the forces acting upon the can and the directions of each force. The two forces acting on the soda pop can are

A) the gravitational force downward and normal force from the table downward.

B) the gravitational force downward and normal force from the table upward.

C) the gravitational force upward and normal force from the table downward.

D) the gravitational force upward and normal force from the table upward.

40) When an object is at rest, and stays at rest, it might have several forces acting on it.

However,

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A) the forces are all in the same direction.

B) there can only beone force opposite gravity, since weight depends on mass.

C) the forcesbalance out to net force of zero.

D) dynamic equilibrium can never be achieved except in the total absence of all forces.

41) In the trajectory of a thrown object, like a baseball, the gravitational force is always downward. However, the force of air resistance is always

A) upward.

B) horizontal.

C) tangent to the trajectory and in the direction opposite the velocity.

D) perpendicular to the trajectory.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

42) A blob of green cheese at the Cheese Institute on the Earth has a mass of 8.1 kg. The same cheese blob in outer space will have a mass of kg.

43) A light body and a heavy body are both given identical accelerations. The body acted upon by the larger force is the body.

44) A light body sliding on a smooth horizontal surface collides with a heavy body. During the instant of contact the force exerted by the light body on the heavy body is (equal to, greater than, less than) the force exerted by the heavy body on the light body.

45) A body of mass 1 kg is pushed across a horizontal table by a force of 2 N. The observed acceleration is 1.7 m/s2. The force of friction opposing the motion is N.

46)

The net force acting on a body gives the direction of the

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47)

The amount of inertia a body has can be measured by finding its

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48)

The force of the floor pushing up on you to counter your weight is an example of a force.

49) Newton's Law states that no force is required to keep a moving object in motion. Why, then, do you have to pedal continuously to ride a bicycle along a flat road? force

50) A ball hangs at rest from a string attached to the ceiling. The string pulls up on the ball with a force equal to its weight. The reaction to the upward force of the string on the ball is a (direction) force exerted by the on the .

SECTION BREAK. Answer all the part questions.

51) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

51.1) An object is acted upon by the three forces shown. In order to move the object upward,

A) any upward force must be applied.

B) an upward force of at least 5 N must be applied.

C) an upward force of at least 25 N must be applied.

D) an upward forceof at least 30 N must be applied.

E) an upward forceof at least 55 N must be applied.

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52) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

52.1) A shiny, spherical, metal alien jumps out of a perfectly good airplane and skydives for a few seconds. Its photographic friend snaps photos of the alien with a special camera that also captures the forces on the object. Refer to the set of snapshots Q, J, Y, and L. Which snapshot depicts the forces just after the parachute has fully opened?

A) Snapshot Q B) Snapshot J C) Snapshot Y D) Snapshot L

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Answer Key Test name: Chap 04_10e 1) C 2) B 3) A 4) A 5) D 6) D 7) C 8) B 9) A 10) A 11) D 12) E 13) C 14) B 15) B 16) D 17) C 18) A 19) D 20) D 21) E 22) C 23) B 24) B 25) C 26) E Version 1

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27) C 28) D 29) B 30) B 31) B 32) C 33) A 34) D 35) E 36) B 37) A 38) E 39) B 40) C 41) C 42) 8.1 43) heavy 44) equal to 45) 0.3 46) acceleration 47) mass 48) normal 49) frictional 50) [downward, ball, string] 51) Section Break 51.1) A 52) Section Break 52.1) C

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Chapter 5: Circular Motion, the Planets, and Gravity MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) Earth's gravity attracts a person with a force of 120 lbs. The force with which the Earth is attracted towards the person is

A) billions andbillions of tons.

B) 120 lbs.

C) small but notzero.

D) zero.

2) Which planets exhibit retrograde motion, that is, periodically appear to reverse their direction of motion across the sky?

A) only Mars, Mercury, and Venus B) only Mars, Jupiter, and Venus C) only Mars, Jupiter, and Saturn D) only Venus, Saturn, and Jupiter E) All of the planets show retrograde motion.

3) After their rocket engines shut off, astronauts experience weightlessness in the orbiting Space Shuttle,

A) but they are notaccelerating, since nothing actually has weight in space.

B) and they areaccelerating because they are actually in free-fall.

C) and they are accelerating because they have constant velocity as they pass overhead.

D) but they cannot accelerate because their rocket engines are shut off.

4) A rock that weighs 100 lb on Earth is taken to the Moon. Which of the following statements accurately describes what would be observed?

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A) The rock is easier to lift because its mass is less on the moon.

B) The rock is easier to lift because its weight is less on the moon.

C) The rock is more difficult to lift because the Moon's radius is less than Earth's.

D) The rock is just as difficult to lift on the Moon as it is on Earth because its mass hasn't changed.

5) For reasons known only to them, a group of extraterrestrials offers you your choice of three gold ingots. One weighs 10 lb on Earth, the second weighs 10 lb on Jupiter, and the third weighs 10 lb on the Moon. To get the most gold, you should choose the ingot that weighs 10 lb on

A) Earth.

B) Jupiter.

C) the Moon.

D) No difference; 10 lbs is 10 lbs wherever you go.

6)

An object weighs 30 newtons on Earth. What is its approximate mass?

A) 640 kg B) 30 g C) 12 kg D) 3 kg E) 294 kg

7)

An object undergoes uniform circular motion. Which pair of vectors is perpendicular?

A) its centripetal acceleration and the centripetal force B) its centripetal acceleration and velocity vectors C) All three vectors are mutually perpendicular: centripetal acceleration, centripetal force, and velocity.

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8)

Which of the following is NOT a vector?

A) acceleration B) mass C) weight D) velocity E) All of these choices are correct.

9) A banked curve in a roadway is designed for a speed of 35 mph. During an ice storm cars should be able to safely negotiate this curve at 35 mph, because at this speed

A) the necessary centripetal force is supplied entirely by gravity.

B) (and at all speeds) the acceleration vector of the car points down, helping maintain stability.

C) the necessarycentripetal force is supplied entirely by the normal force from the road.

D) the centrifugalforce of the car exactly balances the centripetal force.

10) The mass of an apple on the Earth is 0.2 kg. On the Moon, the mass of the same apple would be

A) greater than 0.2kg.

B) 0.2 kg.

C) greater than zerobut less than 0.2 kg.

D) zero.

11) Arnold can bench press 315 pounds in his gym in California. That is exactly six big 45pound weight plates and the 45-pound bar. He can lift all that one time, but he cannot lift 325 pounds even once. At the NASA gym on the Moon, Arnold would

A) be able to bench press more than 315 pounds.

B) be able to benchpress the bar and more than 6 weight plates.

C) be unable to bench press 315 pounds due to weak gravitational field of the Moon.

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12) Six identical blocks of steel, each with mass 10.0 kg, are taken to the Moon. On the Moon, their combined mass is

A) zero.

B) 10.0 kg.

C) 360 kg.

D) 60.0 kg.

13) Two cars that have the same mass are moving around a circular track at the same constant speed. The track is perfectly level. If car 1 is at the inner edge of the track and car 2 is at the outer edge, then

A) the frictionalforce on car 1 is greater than the frictional force on car 2.

B) the frictionalforce on car 1 is less than the frictional force on car 2.

C) the frictional forces on both cars are equal and greater than zero.

D) the frictional force on both cars is zero.

14) A cyclist races around a circular track at the constant speed of 20 m/s. The radius of the track is 40 m. The centripetal acceleration of the cyclist is A) zero.

B) 10 m/s2, toward the center of the track.

C) 10 m/s2, downward.

D) 20 m/s2, in the direction of travel.

15) A man weighs 650 N while on the surface of Earth. If he is transported to the planet Mythos, which has the same mass as Earth but a radius that is five times larger than Earth's, his weight would be

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A) 16,250 N. B) 3,250 N. C) 650 N. D) 130 N. E) 26 N.

16) The orbit of Comet UX209 about the Sun is not a circle but it orbits once every 365 days, just as Earth does. UX209 is closer to the Sun in April than it is in October. Thus, the speed of UX209 as it moves along its orbit is

A) steadilyincreasing all year long.

B) greater in Aprilthan in October.

C) greater inOctober than it is in April.

D) steadily decreasing all year long.

E) the same all year long.

17) An asteroid moving around the Sun happens to experience only negligible forces from other objects in the solar system. The path of this asteroid will be

A) a sinusoid.

B) a parabola.

C) an ellipse.

D) a straight line.

18) A car travels around a curve with constant speed. The correct statement from the following is

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A) the car has anacceleration directed inward toward the center of the curve.

B) the velocity ofthe car is constant.

C) the car has an acceleration directed outward from the center of the curve.

D) the car has zero acceleration.

E) the car has an acceleration directed in the instantaneous direction of the velocity vector.

19) A ball is whirled on the end of a string in a horizontal circle at constant speed. Suddenly, the string breaks. Immediately after the string breaks, the ball will

A) have a horizontal velocity away from the center of the circle.

B) have a horizontal velocity that is tangential to the circle.

C) have a horizontal velocity toward the center of the circle.

D) have a horizontal velocity partly in away from the center of the circle and partly tangent to the circle.

E) have no horizontal velocity.

20) Car A travels with speed v around curve number one, which has a radius r. Car B travels with speed 2v around curve number two, which has a radius 2r. The acceleration will be

A) greater for carA. B) greater for carB. C) zero for bothcars.

D) the same for bothcars.

21) If a ball at the end of a string is whirled in a vertical circle at constant speed, the tension will be

A) the same throughout the motion.

B) greatest at thehighest point in the motion.

C) greatest at thelowest point in the motion.

D) greatest at a point where the string is instantaneously parallel to the ground.

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22)

The first scientist to determine that the orbits of the planets are ellipses was

A) Galileo.

B) Kepler.

C) Ptolemy.

D) Copernicus.

E) Newton.

23) The heliocentric model of the solar system gained preference over the early Greek epicycle model because

A) the heliocentric model gave a more accurate description of observed planetary motions.

B) the heliocentricmodel was simpler.

C) only theheliocentric model could explain retrograde motion.

24) According to Newton's Law of Gravitation, if the distance between two bodies is doubled the attractive force between them becomes

A) unchanged.

B) twice aslarge.

C) half aslarge.

D) four times aslarge.

E) one quarter aslarge.

25) The Sun and Moon both have an effect on the tides. Which one has the larger effect, and why?

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A) the Moon, because its force differs more between the surface and center of the Earth B) the Sun, because its force differs more between the surface and center of the Earth C) the Moon, because it exerts a larger force on the ocean D) the Sun, because it exerts a larger force on the ocean E) Both the sun and Moon equally affect the tides.

26) Suppose a planet has a mass of 10 times that of the Earth and a radius that is 100 times that of the Earth. The acceleration of gravity on the surface of the planet, expressed in units of the Earth's acceleration of gravity, g, is

A) g.

B) 10 g.

C) g/10.

D) 1000 g.

E) g/1000.

27) Suppose an artificial satellite has been put into circular orbit about the Earth, at a distance from the center of the Earth equal to 1/4 the distance from the Earth's center to the Moon's center. In terms of the Moon's period Tm, what will be the period of the satellite?

A) 16 Tm B) 8 Tm C) Tm D) Tm/8 E) Tm/16

28) On a two-lane highway (not divided), a car headed north experiences a centripetal acceleration directed toward the west. Simultaneously, a truck passes the car, headed south in the other lane. The direction of the centripetal acceleration on the truck is

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A) west.

B) east.

C) north.

D) south.

29)

What are the units for the constant G used in Newton's law of universal gravitation?

A) kg2/m2 B) kg m /s2 C) (N m2)/kg2 D) N/m2 E) None of these choices are correct

30) If you are ever fortunate enough to experience a total eclipse of the Sun, you can be sure that it will happen when the Moon is

A) in its "firstquarter" phase.

B) in its "lastquarter" phase.

C) in the "newMoon" phase.

D) full.

E) No way to tell; it's a matter of chance.

31) In Vienna, there is a Ferris wheel designed so that the passengers ride in a standing position. If one of the passengers were standing on a bathroom scale while the ride rotated at a constant speed, the scale would read lowest at

A) the lowest pointin the ride.

B) the highest pointin the ride.

C) the point in the ride where they were ascending most rapidly.

D) the point in the ride where they were descending most rapidly.

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32) During a new Moon, when the Sun and the Moon are on the same side of the Earth, the people who live next to the ocean will see about how many high tides per day?

A) one B) two C) three D) four

33) Two artificial satellites are in circular orbits about the Earth. Which of the two will be moving more slowly along its orbit?

A) the one with the smaller mass B) the one with the larger mass C) the lower one D) the higher one

34)

A full Moon is just now rising. Approximately what time of day is it?

A) 6 PM (sunset) B) midnight C) 6 AM(sunrise) D) noon E) It could be any time of day.

35) If a curve is banked to accommodate cars traveling at 15 m/s, what will happen during an ice storm (no friction with the road) to a car moving at a faster speed?

A) It will gradually slide down the bank.

B) It will continue to follow the curve as if there were no ice.

C) It will gradually slide up the bank.

D) It will slide up the bank and then slide down the bank, oscillating in its vertical position.

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36)

In his model of the motions of the planets, Copernicus

A) assumed that the Earth is the center of the solar system.

B) revived the idea that our solar system is heliocentric (Sun-centered).

C) found that the planets move in paths shaped like ellipses.

D) was able to make predictions that were much more accurate than Ptolemy's model.

37)

In order to move in a perfectly circular path, the net force on an object must

A) always changemagnitude but not direction.

B) always changedirection but not magnitude.

C) always change both magnitude and direction.

D) have a constant magnitude and direction.

E) equal zero.

38) Two stars of different mass move directly toward each other. As the distance between the stars decreases, the speed of the stars

A) gets smaller for both.

B) stays the same for both.

C) increases for both.

D) stays constant for the larger one and increases for the smaller one.

E) stays constant for the smaller one and decreases for the larger one.

39)

If you took a Ferris wheel ride in space while sitting on a bathroom scale, your weight

A) would start smalland continually increase.

B) would be zero forthe entire ride.

C) would be constantand larger than zero for the entire ride.

D) would start large and continually decrease.

E) would increase and decrease just as on Earth.

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40) Two cyclists of different mass take a turn on a level road. They follow the same path and are moving the same constant speed for the turn. Which of the following statements is correct?

A) The acceleration is zero for both.

B) The acceleration is larger for the less massive cyclist.

C) The acceleration is larger for the more massive cyclist.

D) The acceleration is not zero but is the same for both.

If Newton's law of universal gravitation turned out to be Gm1m2/r rather than Gm1m2/r2, 41) tides on Earth

A) would still occur because each side of the Earth would feel a different gravitational force from the Moon.

B) would not happen because the force of gravity from the Moon would be too strong.

C) would not occurbecause the Sun would cancel out the Moon's gravity.

D) would not occur because gravity would then be a repulsive force.

42) If two bicyclists move around a circular track of radius 100 m, at the same speed, 20 m/s, but in opposite directions, then A) one has centripetal acceleration of 4 m/s2 and the other has centrifugal acceleration of 4 m/s2.

B) they have opposite accelerations, +4 m/s2 (inward) and -4 m/s2 (outward).

C) they have equal size accelerations, 4 m/s2.

D) they might havedifferent accelerations, depending on whether they have identical mass ornot.

43) You spin your little brother on a "helicopter" ride, which means you hold hands and spin around a vertical axis, usually resulting in the little brother's feet lifting off the ground. During the "ride", the acceleration of your brother is

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A) inward towardyou, and you must pull him inward.

B) inward towardyou, but you push him outward.

C) tangential to the circular path, and that is why it takes two hands to give helicopter rides.

D) outward from you,but he pushes you inward.

E) outward from you because circular paths always have centrifugal acceleration.

44) When you swing your partner at an old-time square dance, you lock elbows and your partner is also swinging you. As a result, you both move in a circle. For this reason,

A) you must pull your partner toward you and your partner must push you.

B) you both must push outward against each other.

C) you and your partner must simultaneously pull each other.

D) your pull cancels out your partner's pull, making for zero net force and no acceleration.

45) until

Kepler's three laws of planetary motion were useful but not considered fully explained

A) Galileo developed the telescope for astronomical observation.

B) Vivaldi composed his astronomical concerto, "The Four Seasons."

C) Pythagoras developed his famous theorem about right triangles and the Golden Ratio.

D) Newton introduced the law of universal gravitation for astronomical and terrestrial objects.

46) Acceleration due to gravity is 9.8 m/s2 on the surface of Earth, and at orbits 200 miles above the surface of Earth, where the space shuttle orbits, the acceleration is A) greater than 9.8m/s2 .

B) exactly 9.8 m/s2—same as on the surface of Earth.

C) less than 9.8m/s2.

D) undetermined, because it depends on the mass of the spacecraft or satellite.

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FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

47) The of a body decreases as it is moved away from the surface of the Earth.

48)

A body moving in a circular path at constant speed exhibits acceleration because its is changing.

49)

A car can move at constant speed on a level curve on a highway as long as the force of between the pavement and tires is sufficient to provide the necessary centripetal

force.

50)

A car could move at constant speed on an icy curve which is banked for (all, one, no) speed(s) of the car.

51) A person weighing 500 N rides on a Ferris wheel sitting on a bathroom scale. At the highest point of motion, the scale reads 200 N while the person continues to move in a circular path. The centripetal force on the person at this point is N.

52)

To explain the retrograde motion of planets, Ptolemy introduced the concept of .

53) If a person sits on a bathroom scale while riding on a Ferris wheel, the reading on the scale will be lowest while passing through the point (indicate a point in the path).

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54) Two satellites are launched into circular orbits about the Earth. The one closer to the Earth has a period of 90 minutes. The one farther away will have a period which is (longer than, shorter than, or the same as) 90 minutes.

55) If the Earth rotated more slowly so that the length of a day was longer, the radius of a communications satellite in synchronous orbit would be .

56)

A lunar eclipse can only happen when the moon is

(what moon phase).

Strictly speaking, Newton's law of universal gravitation, F = Gm1m2/r2, is valid only if 57) the masses are either point masses or .

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Answer Key Test name: Chap 05_10e 1) B 2) E 3) B 4) B 5) C 6) D 7) B 8) B 9) C 10) B 11) B 12) D 13) A 14) B 15) E 16) B 17) C 18) A 19) B 20) B 21) C 22) B 23) B 24) E 25) A 26) E Version 1

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27) D 28) A 29) C 30) C 31) B 32) B 33) D 34) A 35) C 36) B 37) B 38) C 39) C 40) D 41) A 42) C 43) A 44) C 45) D 46) C 47) weight 48) velocity 49) friction 50) one 51) 300 52) epicycles 53) highest 54) longer than 55) larger 56) full Version 1

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57) perfect (uniform) spheres

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Chapter 6: Energy and Oscillations MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) Which of the following is not an energy unit?

A) N·m B) Joule C) Watt D) calorie E) kWh

2)

If work was done on an object, the object must have

A) changed only itsdirection of motion.

B) accelerated.

C) experienced a frictional force.

D) changed itsposition.

3) A brick slides across a horizontal rough surface and eventually comes to a stop. What happened to the kinetic energy of the brick?

A) Nothing; it is still in the brick but is now called potential energy.

B) It was converted to other energy forms, mostly heat.

C) It was converted to a potential energy of friction.

D) It was simply destroyed in the process of stopping.

4)

Which of the following is possessed by a moving object, but not by a stationary object?

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A) energy B) mass C) inertia D) kinetic energy

5)

The power of an engine is a measure of

A) the rate at whichit can perform work.

B) its volume.

C) its ability tooutperform a horse.

D) the total amount of work it can perform.

6) Which has the greater kinetic energy—a 1-ton car moving at 30 m/s or a half-ton car moving at 60 m/s?

A) the half-ton car B) the 1-ton car C) Both have the same kinetic energy.

D) It cannot be determined because the mass of the cars can't be found.

7) A 20 N ball and a 40 N ball are dropped at the same time from a height of 10 meters. Air resistance is negligible. Which of the following statements is accurate?

A) After 1 second has elapsed, both balls have the same kinetic energy, since they have the same acceleration.

B) The heavy ball has a greater acceleration and falls faster.

C) Both balls hit the ground at the same time but gravity does more work on the heavy ball than on the light ball.

D) The light ball has a greater speed, since it can accelerate faster than the heavy ball.

8)

When work is done by a force on an object, which of the following is true?

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A) The speed of the object must change.

B) The object does an equal amount of work on the force.

C) The work done is equal to the change of total kinetic energy of the object plus any energy appearing as heat, light, or sound.

D) The object must change height above the ground.

E) The force cannot take energy away from the object.

9) A block sits on a slight incline, held at rest by the frictional force between the block and the incline. Which of the following statements is true?

A) The frictional force performs no work, since there is no motion of the block.

B) The work by the frictional force is equal to the gravitational potential energy of the block.

C) The work done by the frictional force is negative, since the force of friction opposes the direction that the block is being tugged by gravity.

D) The work done by gravity is entirely converted into heat because of the friction present.

E) None of these choices are true.

10) Initially, a blue automobile has twice the kinetic energy that a red automobile has. Both are braked to a stop; both have the same amount of braking force. The red auto will stop in as the blue auto.

A) half thedistance B) the same distance C) twice the distance D) four times the distance E) one fourth the distance

11) A mass hangs from a spring that is fixed to the ceiling. The mass is now pulled down and released so the mass oscillates up and down. Which of the following statements is true?

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A) The kinetic energy of the oscillating mass is a constant.

B) Adding mass to the spring will make it oscillate faster.

C) The restoring force of the spring is equal to the weight of the mass.

D) The gravitational force on the mass oscillates at the same frequency as the mass.

E) None of these choices are true.

12) Jim exerts a force of 500 N against a 100-kg desk that does not move. Virgil exerts a force of 400 N against a 60-kg desk that moves 2 m in the direction of the push. Mik exerts a force of 200 N against a 50-kg desk that moves 5 m in the direction of the push. The most work is done by

A) Jim. B) Virgil.

C) Mik. D) Virgil and Mik, who do equal amounts of work.

13) Suppose you climb the stairs of an eight-story building, about 24 m high, and your mass is 70 kg. The gravitational potential energy you gain is about

A) 16,500calories.

B) 40 calories.

C) 16,500 Joule.

D) 40 Joule.

14) Virgil rides a skateboard (combined mass 100 kg) at 4 m/s, and Jill rides a bicycle (combined mass 64 kg) at 5 m/s.

A) Virgil has the greater kinetic energy.

B) Jill has thegreater kinetic energy.

C) Virgil and Jillhave equal kinetic energies.

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15) An object with a kinetic energy of 40 J is stopped in a distance of 0.01 m. The average force that stops the object is

A) 40,000 N. B) 4,000 N. C) 400 N. D) 40 N. E) 0.4 N.

16) A quarterback of mass 85 kg is running at 10 m/s. Also, a tackle of mass 100 kg is running at 9 m/s.

A) The tackle has the greater kinetic energy.

B) The quarterback and the tackle have equal kinetic energies.

C) The quarterback has the greater kinetic energy.

17)

For a 0.2-kg frog to jump to a height of 0.6 meter requires an energy of about

A) 12 Joule.

B) 1.2 Joule.

C) 0.6 Joule.

D) 6.0 Joule.

18) A 3.0-kg cat runs to the left at 10 m/s and a 8-kg dog runs to the right at 4.0 m/s. The total kinetic energy is

A) -35 Joule.

B) 0.

C) -86 Joule.

D) 146 Joule.

E) 214 Joule.

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19) A child riding on a swing, Andrea, rises to a height 1.0 m above the lowest point.

Another child of equal mass, Brian, has a speed at his lowest point that is twice as great as Andrea’s speed at her lowest point. Brian will rise

A) to a height whichdepends on the mass.

B) to the sameheight.

C) twice ashigh.

D) four times ashigh.

20) A box is moved 10 m across by a floor a force of 25 N acting along the direction of motion. The work done by the force is

A) 250 J. B) 125 J. C) 35 J. D) 25 J. E) 2.5 J.

21) A box is moved 20 m across a smooth floor by a force making a downward angle with the floor, so that there is effectively a 10 N force acting parallel to the floor in the direction of motion and a 5 N force acting perpendicular to the floor. The work done is

A) 300 J. B) 200 J. C) 100 J. D) 20 J. E) 5.0 J.

22) A box is pushed across a rough horizontal floor by a force acting parallel to the floor in the direction of motion. A force doing negative work on the body is

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A) gravity.

B) the appliedforce.

C) friction.

D) the normal reaction force of the floor upward on the body.

E) a fictitious force.

23) A box is pushed across a rough horizontal floor by a force acting parallel to the floor in the direction of motion. A force doing no work during the motion is

A) the appliedforce.

B) gravity.

C) friction.

D) All of the forces are doing work.

24) The kinetic energy of a body is correctly given by which of the following expressions? (m=mass, v=speed)

A) mv B) 2mv2 C) mv2 D) (½)mv2 E) (½)mv

25) A refrigerator weighing 1500 N is to be lifted onto a truck bed that is 1.0 m above the ground. When pushed up a slanting ramp 2.0 m in length a force of only 750 N is required to move it at constant velocity. Neglecting friction and comparing the work involved in lifting the refrigerator straight up to the work in pushing it along the ramp, there is A) less work required when the ramp is employed.

B) more work required when the ramp is employed.

C) an equal amount of work is required in each case.

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26)

Which of the following is not a unit of power?

A) watt B) kilowatt C) joule/second D) kilowatt-hour E) horsepower

27) If the speed of a car is doubled but the brakes apply the same force, the distance required to stop the car changes by a factor of

A) ¼.

B) ½.

C) 1.

D) 2.

E) 4.

28) A painter of mass 70 kg climbs 3.0 m up a ladder. The painter's potential energy has increased by

A) 2058 J. B) 1029 J. C) 686 J. D) 261 J. E) 210 J.

29) by

The potential energy of a spring of constant k that has been stretched a distance x is given

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A) B) kx.

C) D) kx2.

E)

30)

A pendulum swings through 10 cycles in 2 seconds. The frequency of the pendulum is

A) 10 Hz. B) 5 Hz. C) 2 Hz. D) 0.5 Hz. E) 0.1 Hz.

31) A grandfather clock that is regulated by a pendulum is taken to the Moon, where the acceleration of gravity is less. Compared to an identical clock on Earth, the grandfather clock on the Moon will

A) run fast.

B) keep time at the same rate.

C) run slow.

32) A mass hangs on a spring held in a physicist's hand. When the mass is pulled down and then released, it oscillates with a period of 2.0 s. This system is taken to the Moon, where the acceleration of gravity is less. The spring on the Moon is held in an astronaut's hand, and the mass, when pulled down and released, will

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A) oscillate with a longer period.

B) oscillate with an unchanged period.

C) oscillate with a shorter period.

D) not oscillate at all.

33) A grandfather clock that is regulated by a pendulum is orbiting the Earth aboard the space station. Compared to an identical clock on Earth, the grandfather clock aboard the space station will

A) run fast.

B) keep time at the same rate.

C) run slow.

D) not run at all.

34) A mass hangs on a spring held in a physicist's hand. When the mass is pulled down and then released, it oscillates with a period of 2.0 s. This system is taken to the space station orbiting the Earth. The spring is held in an astronaut's hand, and the mass, when pulled down and released, will

A) oscillate with a longer period.

B) oscillate with ashorter period.

C) oscillate with anunchanged period.

D) not oscillate at all.

35)

In order for a body to exhibit simple harmonic motion there must be

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A) a constant force pushing the body away from the center.

B) a constant force drawing the body toward the center.

C) a force pushingthe body away from the center and increasing with distance away from thecenter.

D) a force drawingthe body toward the center and increasing with distance away from thecenter.

E) a force drawing the body toward the center and decreasing with distance away from the center.

36) A ball at the end of a string is swinging as a simple pendulum. Assuming no loss in energy due to friction, we can say for the ball that

A) the potential energy is maximum at each end of the motion.

B) the mechanical energy changes and is maximum where the kinetic energy is minimum.

C) the mechanical energy changes and is maximum where the kinetic energy is maximum.

D) the kinetic energy does not change but the potential energy does.

37) A body is suspended from a spring hanging vertically. The body is then pulled downward so the spring stretches. Consider the change in the elastic potential energy (EPE) of the spring and the change in gravitational potential energy (GPE) as the body is pulled down.

A) The GPE decreases while the EPE increases.

B) The GPE decreases but the EPE is unchanged.

C) The EPE increases but the GPE is unchanged.

D) The GPE increases along with the EPE. E) Both the GPE and the EPE decrease.

38) A bullet of mass 0.010 kg and speed of 500 m/s is brought to rest in a wooden block after penetrating a distance of 0.20 m. The work done on the bullet by the block is

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A) -1250 J. B) 1250 J. C) -2.5 J. D) 2.5 J. E) zero.

39) On a frictionless tabletop, a force is applied to an object: the object's velocity is horizontal and the force is perpendicular to the tabletop. Which of the following is true?

A) The applied force is friction.

B) The total energy of the object does not change.

C) There cannot be more than one force on the object.

D) The force does work on the object.

40) A worker in a warehouse uses a rope passing through some pulleys to lift a heavy crate.

The worker exerts a force five times less than the weight of the crate but has to move the rope four times as far as the crate moves. This situation

A) can happen because the extra distance traveled makes up for the smaller force applied.

B) can happen because there is friction in the pulleys so the work done by the worker will not equal the work done on the crate.

C) cannot happen because a crate that heavy would lift the worker, rather than the worker lifting the crate.

D) cannot happen because the work done by the worker is less than the work done on the crate.

41)

Work is done on an object to increase its total energy. Which one of the following is true?

A) The total work done must be equal to the energy lost to heat and sound.

B) Both the kinetic energy and potential energy can increase.

C) If the potential energy increases, then the kinetic energy must decrease.

D) The object must have a larger speed and smaller height above the ground.

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42) Two springs are hung from a ceiling and carry identical masses. The first spring has a spring constant twice as large as the second spring. The masses on each spring are pulled down from their equilibrium positions the same distance and are then released. The amplitude of the oscillation is

A) the same for bothsprings.

B) larger for thefirst spring.

C) larger for the second spring.

D) It is not possible to know which is larger without knowing the mass.

43) A mass attached to a spring is drawn back 2 cm from equilibrium and released. If a second spring were used that had a smaller spring constant than the first but the mass was the same, which of the following would be larger?

A) amplitude B) frequency C) period D) initial restoring force

44)

If the kinetic energy of an object increases, then

A) the potential energy must decrease.

B) the total energy must increase.

C) there can only be one force on the object.

D) the speed must increase as well.

45)

If an object has a larger potential energy than kinetic energy,

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A) the speed of the object will increase.

B) the speed of the object will not change.

C) the speed of the object will decrease.

D) It is not possible to predict what the speed will be; it depends on the situation.

46)

A simple machine allows you to move .

masses even though you apply

A) larger; smallerforce over a longer distance B) smaller; kineticenergy spread over the entire path C) stationary but not moving; many Newtons of force D) smaller; potential energy deficits

47) Can the gravitational force of Earth do positive or negative work on a geosynchronous communication satellite, once it is on its circular orbit?

A) No, because the satellite has zero acceleration.

B) No, because the force is always perpendicular to the orbital path.

C) Yes, because centripetal forces always do positive work.

D) Yes, because its speed is constant.

48) When you lift a heavy 5.0 kg crate straight up from ground level to a height of 2.0 m above ground level, then you have changed the crate's gravitational potential energy by A) 98 m2/s2.

B) 98 J. C) an undetermined amount, because it depends on how fast you lifted it.

D) 98 N. E) 98 kg m/s.

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49) The potential energy of a spring is 0.3 J when it is compressed 0.04 m to the left of its equilibrium position. This is its leftmost position. What is its kinetic energy at this point?

A) -0.3 J B) zero C) 0.3 J D) 375 N/m

50) The potential energy of a spring is 0.3 J when it is compressed 0.04 m to the left of its equilibrium position. This is its leftmost position. What is its kinetic energy when it returns to the equilibrium point?

A) 0.25 J and moving to the right B) zero C) -0.25 J and moving to the left D) 0.25 J and at rest

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

51) A spring wound clock makes use of energy to drive the mechanism.

52) A horizontal force acts on a block that is initially at rest but free to move across a smooth horizontal surface. The work done by this force (increases; does not change; decreases) the kinetic energy of the block.

53) In pole-vaulting, in addition to gravitational potential energy there is potential energy in the bent pole which is analogous to potential energy stored in a under compression.

54) Other things being equal, the pole-vaulter having the greatest going into the jump should jump the highest.

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55)

A small radio-controlled car's motor rated at 6 watts output is capable of performing Joules of work in 15 seconds.

56) The swing.

of a pendulum is the amount of time the pendulum takes for one full

57) When a force acts in a direction opposite to the motion, done on the object.

work is said to be

58) A ball of mass 5 kg attached to a string is swung in a horizontal circle of radius 0.5 m. If the tension in the string is 10 N, the work done by the tension in one revolution is J.

59)

Total mechanical energy of a system is conserved when there are no forces doing work on the system.

60) The conversion of the initial potential energy of a person on a sled on a smooth icy slope into kinetic energy at the bottom is an example of the principle of conservation of .

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Answer Key Test name: Chap 06_10e 1) C 2) D 3) B 4) D 5) A 6) A 7) C 8) C 9) A 10) A 11) E 12) C 13) C 14) C 15) B 16) C 17) B 18) E 19) D 20) A 21) B 22) C 23) B 24) D 25) C 26) D Version 1

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27) E 28) A 29) E 30) B 31) C 32) B 33) D 34) C 35) D 36) A 37) A 38) A 39) B 40) D 41) B 42) A 43) C 44) D 45) D 46) A 47) B 48) B 49) B 50) A 51) elastic potential 52) increases 53) spring 54) kinetic 55) 90 56) period Version 1

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57) negative 58) zero 59) non-conservative 60) energy

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Chapter 7: Momentum MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) When a baseball bat hits the ball, the impulse delivered to the ball is increased by

A) "followthrough" on the swing, which increases contact time.

B) rapidly stopping the bat after impact.

C) letting the bat recoil upon impact.

D) The impulse cannot be changed.

2)

One form of the proper metric unit for momentum is

A) Joule.

B) Kg·m.

C) Kg·m/s2.

D) N·sec.

3) Suppose you are out on a frozen lake, where there is no friction. Which of the following would start you moving towards the shore?

A) shouting at someone on the shore B) removing a shoe and throwing it away from the shore C) removing a shoe and throwing it towards the shore D) None of these choices would work.

4) A gun is made of a super-low-weight but strong material. The bullet for the gun is more massive than the gun itself. For such a gun

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A) recoil problems would be lessened.

B) the gun, if unsupported, would have a recoil velocity higher than the bulletvelocity.

C) conservation of momentum is not satisfied.

D) the bullet would go faster with less powder.

5)

The purpose of an air bag in an auto is to

A) decrease the forceapplied to you during a collision.

B) reduce the impulseon you during a collision.

C) make your momentumchange occur over a shorter time during a collision.

D) reduce your speedjust before a collision.

6) A bowling ball, moving to the east at a speed of 1.4 m/s, collides head-on with a stationary beach ball of the same diameter but less than one twentieth the mass. After the collision, the beach ball moves with a speed of 1.6 m/s. Which of the following is then true?

A) The bowling ball has a velocity of slightly under 1.4 m/s, to the east.

B) The beach ball has more momentum than the bowling ball.

C) The bowling ball recoils to the west with nearly the same speed as before the collision.

D) The bowling ball and the beach ball have the same momentum after the collision.

7) Which of the following mathematical expressions should be used to calculate the momentum of an auto?

A) weight × speed B) mass ×acceleration C) weight × force D) mass ×velocity

8)

The momentum of a truck is increased by a factor of 2; its weight does not change. Thus,

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A) its acceleration is doubled.

B) its speeddoubled.

C) its speedincreased by a factor of 4.

D) its kinetic energy doubled.

9)

A quantity which is conserved in the collision of a car and a truck is

A) kinetic energy.

B) potential energy.

C) momentum of the car.

D) momentum of thetruck.

E) totalmomentum.

10) A ping-pong ball is dropped vertically onto a stationary bowling ball resting on the floor.

Which of the balls experiences the greater force as a result of the collision?

A) the bowling ball B) the ping-pong ball C) Neither, both experience forces of the same size.

D) It's impossible to tell from this data.

11)

A tennis ball bounces off a brick wall. Which of the following is true?

A) The total momentum of the ball, wall, and Earth is conserved in this process.

B) The momentum of the ball is conserved in this process.

C) If the collision is elastic, then the ball's velocity does not change in this process.

D) None of these choices are true.

12) Object A moving due east collides with object B moving due west. After the collision, A is moving 20° north of due east. What must be true of B after the collision?

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A) B must be moving 20° south of due east.

B) B must be moving 20° south of due west.

C) At least part of B's velocity must be toward the south.

D) At least part of B's velocity must be toward the west.

E) None of these choices are true.

13) Force F, acting for time T and over a distance D, gives impulse I. To get the same impulse using half the force, it would be necessary for the force to act

A) over a distance 2D. B) over a distance 4D. C) over half the distance D. D) for a time 2T. E) for half the time T.

14) An 80-kg football player travels to the right at 8 m/s and a 120-kg player on the opposite team travels to the left at 4.0 m/s. The total momentum is

A) 240 kg m/s to the left.

B) 160 kg m/s to theright.

C) zero.

D) 160 kg m/s to theleft.

E) 1120 kg m/s to theright.

15) Two people sit face to face on nice skateboards that are free to roll without friction. They push each other with a force of 40 N and move apart. Person X, whose mass (including the skateboard) is 50 kg, moves to the left at 3 m/s. Person Z, whose mass (including the skateboard) is 60 kg,

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A) moves to the right at 2.5 m/s.

B) moves to the right at 1 m/s.

C) moves to the right at 4 m/s.

D) moves to the right at 10 m/s.

16) In attempting to pull a 1500-kg car out of a ditch, Arnold exerts a force of 300 N for three seconds, Bob exerts a force of 500 N for two seconds, and Cecil exerts a force of 200 N for four seconds. Who provided the greatest impulse?

A) Arnold B) Bob C) Cecil D) They all exert an equal impulse on the car.

17) A 30-kg child runs at 3.0 m/s and jumps onto a shopping cart and holds on for dear life.

The cart has a mass of 20 kg. Assuming the child rides on the cart after the collision, the speed of the child and shopping cart just after the child jumps on is

A) zero.

B) 1.8 m/s.

C) 2.5 m/s.

D) 3.0 m/s.

18) In a head-on automobile collision, a person's momentum could be reduced from 2000 kg m/s to zero in just 0.1 s. If this occurs, the average force exerted to stop the person is

A) 20,000 N. B) 2,000 N. C) 200 N. D) This can't be answered without knowing the person's mass.

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19) A child runs at 3.0 m/s and jumps onto a sled, initially at rest. If the child's mass is 36 kg, and if the child and sled slide off together at 2.0 m/s after the collision, the sled's mass is

A) 12 kg.

B) 18 kg.

C) 36 kg.

D) 48 kg.

20) A fire fighting vehicle of mass 12,000 kg is at rest but free to roll with no resistance. If you push it forward with a force of 500 N, the momentum at the end of 10 s of pushing will be

A) 5000 kg m/s.

B) 20,000 kgN/s.

C) 0.416 m/s.

D) zero.

21)

The average force required to accelerate a 0.20-kg ball from rest to 30 m/s in 0.002 s is

A) 75,000 N. B) 15,000 N. C) 3,000 N. D) 0.003 N

22) A friend drops a package to you from a window 16 feet above where you first catch it. It drops an additional 3 feet as you bring it to a stop with a constant force. In order to calculate the force required, you need

A) the time it takesfor you to stop the package.

B) the mass of the package.

C) no additionalinformation.

23)

The principle that total momentum does not change during a brief collision is a result of

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A) the definition of the kilogram.

B) the definition of the newton.

C) Newton's firstlaw and Newton's second law.

D) Newton's first law and Newton's third law.

E) Newton's second law and Newton's third law.

24) A box is moved 10 m across a smooth floor by a force F making a downward angle with the floor, so that there is effectively a 4 N force acting parallel to the floor in the direction of motion and a 3 N force acting perpendicular to the floor. The force F acts for 20 seconds. The impulse delivered to the box by the floor during this process has magnitude

A) 100 Ns. B) 80 Ns. C) 60 Ns. D) zero.

E) Can't tell without knowing the weight of the box.

25) A box is pushed eastward across a rough horizontal floor by a force acting parallel to the floor. A force providing an impulse directed westward on the body is

A) gravity.

B) the appliedforce.

C) friction.

D) normal reaction force of floor upward on body.

E) a fictitiousforce.

26) A box is pushed across a rough horizontal floor by a force acting parallel to the floor in the direction of motion. A force providing no impulse during the motion is

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A) gravity.

B) friction.

C) the applied force.

D) None of these choices are correct.

27) A 3 kg block, initially moving due east at 6 m/s, is acted upon by an impulse having magnitude 6 Ns and direction due west. The final velocity of the block is

A) 8 m/s east.

B) 4 m/s east.

C) 4 m/s west.

D) 8 m/s west.

28) Moving at a constant speed, an elevator lifts a 1000 N package 10 meters in 3 seconds.

During this time, the impulse delivered to the package by the elevator floor is

A) 10,000 Ns up.

B) 3,000 Ns up.

C) 10,000 Nm up.

D) zero.

29)

Collisions between which pairs of objects is likely to be most nearly elastic?

A) a steel ball and a cotton ball B) two steel balls C) a steel ball and a baseball D) two baseballs

30)

If the speed of a car is tripled, the impulse required to stop the car changes by a factor of

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A) 9.

B) 3.

C) 1.

D) 1/3.

E) 1/9.

31) A painter of mass 80 kg climbs 3.0 m up a ladder. The painter has gained momentum in the amount of

A) 240 J. B) 784 J. C) 2352 J. D) Can't say without knowing his velocity change (if any)

32) During a collision, which of these is an indication that the total kinetic energy has changed?

A) Heat is generated.

B) Deformation occurs.

C) Sound is produced.

D) All of these choices are indication that the kinetic energy has changed.

E) None of these choices are correct.

33) Suppose a ball is dropped from shoulder height, falls, makes a perfectly elastic collision with the floor, and rebounds to shoulder height. Compare the magnitudes of the impulses delivered to the ball by gravity and by the floor during this entire motion.

A) The impulse delivered by the floor is half as large as the impulse delivered by gravity.

B) The impulse delivered by the floor is twice as large as the impulse delivered by gravity.

C) The two impulses have the same magnitude.

D) The floor delivers an upward impulse, but gravity does not deliver a total impulse.

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34) Although Newton's second law, F = ma, is valid for collisions, it is difficult to use it generally in this form for collisions because

A) the acceleration is too small.

B) the force F is not constant.

C) the acceleration occurs during a time interval too short to measure easily.

D) the acceleration is too small and the force F is not constant.

E) the force F is not constant and the acceleration occurs during a time interval too short to measure easily.

35) Suppose two boys are trapped on the ice atop a frozen pond, and that the ice is completely frictionless. The boys are initially at rest, but they do have a baseball. They begin to play catch with the ball. Which of these is true?

A) The boys only move while the ball is in the air.

B) They will be stuck on the ice until rescued.

C) The more times they throw and catch the ball, the faster they will get to shore.

D) If after a few throws the ball is not caught and rolls away, the boys will be stuck on the ice.

36) A bullet of mass 0.010 kg and speed of 200 m/s is brought to rest in a wooden block after penetrating a distance of 0.30 m. This process takes 0.04 second. The magnitude of the impulse delivered to the bullet by the block during this time is

A) zero.

B) 0.98 N. C) 1.0 Ns. D) 2.0 Ns. E) 4.0 Ns.

37) A bullet is fired into a wall and comes to rest. Considering only the bullet as the system we can say that

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A) the total kinetic energy is conserved.

B) the momentum is conserved.

C) neither totalkinetic energy nor momentum is conserved.

D) both totalkinetic energy and momentum are conserved.

38) A car moving east collides with a truck moving north. The vehicles have the same speed but the truck has twice the mass of the car. If the vehicles stick together after the collision, what is the path followed by the vehicles after the collision?

A) A B) B C) C D) D E) E

39) A racquetball is dropped from a height of one meter. It bounces off the floor and rises toa height of 0.8 m. The collision with the floor was

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A) an elasticcollision.

B) a partiallyinelastic collision.

C) a perfectlyinelastic collision.

D) impossible to tell without knowing the mass of the ball.

40) A toy car and a toy truck at rest have a compressed spring in between them. The truck has more mass than the car. The spring is released and the two cars move in opposite directions.

Which of the following is true?

A) The magnitude of the truck's momentum is the same as the car's.

B) The magnitude of the truck's momentum is larger than the car's.

C) The magnitude of the truck's momentum is smaller than the car's.

D) It is not possible to tell which has more momentum without knowing the speeds.

41) Consider a system containing three objects that move with different velocities. The objects can interact with each other through forces. In this system

A) the total kinetic energy of the objects will not change unless an outside force is applied.

B) the objects can only collide if an outside force is applied.

C) any collisions between the objects must be elastic.

D) the total momentum of the objects cannot change unless an outside force acts on the system.

42)

If a single force acts on a moving object

A) the momentum ofthe object will change only if the force is in the same direction as thevelocity of the object.

B) the momentum ofthe object must change.

C) the momentum of the object can only change magnitude, not direction.

D) the momentum of the object can only change direction, not magnitude.

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43) Two astronauts of equal mass are holding on to each other and moving at a speed of 30 m/s. They push off of each other and one of the astronauts moves in the same direction as the two were initially moving but at 60 m/s. The velocity of the second astronaut is

A) 60 m/sbackward.

B) 30 m/sbackward.

C) zero.

D) 30 m/sforward.

E) 60 m/s forward.

44) If you were standing on a cart that was at rest and free to roll (ignore friction) and someone threw a 10 kg ball at you, you would

A) not move if youcaught the ball because you are more massive than the ball.

B) roll backwardfaster if you caught the ball.

C) roll backwardfaster if the ball bounced off of you elastically.

D) roll backwardfaster if you caught the ball higher above the ground.

45) An oil tanker heading due west, straight into a strong wind, reaches a speed of 5 m/s and then shuts down its engines to drift. The forward-facing flat surfaces of the tanker catch a total of 60,000 N of force from the wind. This wind force is pointing backwards, to the east. The tanker's mass is 100,000 metric tons, which is 100 million kg. If the wind blows at the same strength for 5 minutes, then how much has the wind changed the tanker's speed?

A) 1.2 m/s B) 1.08 m/s C) 0.018 m/s D) 0.18 m/s

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46) A robot spacecraft is sent to Mars to explore the Martian polar ice cap. Designers can surround it with a set of inflatable balloons that pop out like automobile air bags as soon as the spacecraft's re-entry parachute opens up.

When the spacecraft lands, it will be able to roll for a few meters across the surface of Mars. The popout balloons have an advantage to the spacecraft, because A) they cancel outthe normal force of the surface of Mars.

B) they decrease thekinetic energy.

C) they increase thetime of impact and lessen the stopping force.

D) the impulse that stops the spacecraft for landing is less with these balloons.

47) A rocket obeys the principles of recoil. However, it is much more difficult to apply Newton's second law to a rocket because

A) Newton's three laws do not apply in outer space.

B) there is actuallysideways momentum, because a rocket motor is just a wellcontrolledexplosion.

C) the rocket pushesagainst air but the air is a fluid.

D) as the rocketmotor fires the total mass of the rocket changes.

48) When a single boxcar in the freight yard hooks onto a stationary string of four boxcars, there is some kinetic energy lost. Which of the following could account for the missing energy?

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A) Sound energy in the loud CLANG when they hook together.

B) Heat energy in the clamping mechanism between cars as it opens and then captures the fifth boxcar.

C) Sound energy in the loud CLANG when they hook together and heat energy in the clamping mechanism between cars as it opens and then captures the fifth boxcar.

49) A big defensive lineman picks up a fumbled football and begins rumbling toward the end zone. His mass is 150 kg, and his velocity is 6.0 m/s, west. A brave wide receiver, whose mass is 90 kg, must stop that lineman and he is right in the lineman's path, so it has to be a head-on collision. How fast must the wide receiver be running if he wants to drop the lineman in his tracks and save the day?

A) 88 mph B) 0.60 m/s C) 8.3 m/s D) 10 m/s

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

50) The total momentum of a system will change during a collision unless the force is zero.

51) If heat, sound, or deformation of solid bodies results from a collision, there will be a change in the total .

52) A moving cue ball strikes another ball of equal mass that is initially at rest on the flat planar surface of the pool table. If the collision is elastic, the direction of the velocity of the cue ball after the collision will be to the direction of the velocity of the other ball.

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53)

The impulse required to bring an auto to a stop is ordinarily provided by forces.

54)

If a bullet is fired into a wooden block and remains lodged in the block, the collision was .

55) was

If a bullet is fired into a solid wooden block and comes out the other side, the collision inelastic.

56) If the same impulse is applied to a ping-pong ball and a baseball, the change in the pingpong ball's momentum will be the baseball's.

57) A force acts on an object for a time. If one eighth the force had acted for twice as long, the impulse would have been as much as before.

58) A 60 kg boy standing on a skateboard with frictionless wheels and negligible mass throws a 3 kg ball straight up with a speed of 4 m/s. If the boy was at rest before the throw, his speed after the throw will be .

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Answer Key Test name: Chap 07_10e 1) A 2) D 3) B 4) B 5) A 6) A 7) D 8) B 9) E 10) C 11) A 12) C 13) D 14) B 15) A 16) B 17) B 18) A 19) B 20) A 21) C 22) B 23) E 24) E 25) C 26) D Version 1

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27) B 28) B 29) B 30) B 31) D 32) D 33) C 34) E 35) C 36) D 37) C 38) B 39) B 40) A 41) D 42) B 43) C 44) C 45) D 46) C 47) D 48) C 49) D 50) external 51) kinetic energy 52) perpendicular 53) frictional 54) inelastic 55) partially 56) the same as Version 1

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57) one quarter 58) zero

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Chapter 8: Rotational Motion of Solid Objects MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) An isolated object is initially spinning at a constant speed. Then, although no external forces act upon it, its rotational speed increases. This must be due to

A) an increase in the rotational inertia.

B) an increase in the mass.

C) an increase in the angular momentum.

D) a decrease in the rotational inertia.

E) impossible, angular momentum conservation is violated.

2)

The bigger diameter gears on the rear wheel of a multi-speed bike allow the rider to

A) increase the rotational inertia of the wheel.

B) exert more forceon the wheel.

C) exert more torqueon the wheel.

D) decrease the rotational inertia of the wheel.

3) Three horses are side-by-side on a merry-go-round: one at the edge, one near the axis, and one in between. Each horse has the same rotational speed. Which horse has the greatest linear speed?

A) the horse at the edge B) the horse in the middle C) the horse nearest the axis D) The linear speed is the same for all three horses.

4) A hoop and a sphere have the same diameter and the same mass. Which one will have a larger rotational inertia?

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A) the hoop B) the sphere C) Both will require the same time to reach the bottom.

5)

A torque acting on a body tends to produce

A) equilibrium.

B) linear velocity.

C) a new center of gravity.

D) rotational motion.

6)

The angular momentum of an isolated object can be changed only by

A) changing its rotational inertia.

B) applying atorque.

C) applying a forcealong the axis of rotation.

7)

The rotational inertia of an object depends on

A) its color.

B) how fast it is spinning.

C) how its mass isdistributed about the spin axis.

D) the amount oftorque applied to it.

E) None of these choices are correct.

8) A football thrown with a spinning motion is more stable than one thrown without spin because

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A) there is no net torque on a spinning object.

B) air flows more easily around spinning objects.

C) the torquegenerated by the spinning action is conserved.

D) the angularmomentum of a spinning object can only be changed by applying a torque.

9) An object is moving in a horizontal circle, in a clockwise direction (as viewed from above). In which direction does its angular momentum vector point?

A) to the viewer's left B) away from the viewer C) toward the viewer D) from the ball toward the center of the circle

10)

Using a longer-handled wrench to loosen a tight nut allows you to

A) exert more force on the nut.

B) apply more torqueto the nut.

C) increase the rotational inertia of the nut.

D) pull harder on the wrench.

11) A figure skater is spinning with her arms extended. She now pulls her arms close to her body. What happens?

A) Her rotational acceleration decreases.

B) Her rotational inertia decreases.

C) The net external torque on her increases.

D) Her lever arm gets shorter.

12) A dancer begins performing a pirouette with arms extended. (A pirouette is a complete spin about a vertical axis.) This motion is completed most easily when the rotational inertia is decreased by

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A) bending at thewaist at a right angle.

B) extending the arms and one leg straight out to the sides.

C) holding the arms straight up and extending one foot straight out to the side.

D) bringing the arms and legs in a line with the body.

13) Because the rotational inertia is higher, it is hardest in springboard diving to perform a forward somersault in

A) the straightposition (no bending at knees or waist).

B) the pike position(bending at the waist but not the knees).

C) the tuck position (bending at both the waist and knees).

14) When a bicycle pedal is at the top of its motion, you can exert the greatest torque on the crank by

A) pushing straight down on the pedal with your foot.

B) hooking your toesunder the pedal and pulling upward.

C) pushing straightforward on the pedal with your foot.

15) A solid disk and a hollow disk with the same mass and diameter are released together (from rest) to roll down an incline. The solid disk reaches the bottom first. From this information we can say that the rotational acceleration was

A) larger for thehollow disk.

B) larger for thesolid disk.

C) the same for both disks.

D) impossible to know without a measurement of time.

16) In a stable stack of identical boards at the edge of a table, the center of gravity of the top board

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A) must lie above the table.

B) need not lie overanything.

C) must lie above the bottom board.

D) must lie abovethe next lower board.

17)

You stand with your heels against a wall and bend ninety degrees forward at the waist.

A) You fall forward because your center of gravity moves ahead of your base of support.

B) You fall forwardbecause of the momentum you gain when you move.

C) You are able tomaintain your balance.

D) You fall forward because the muscles in your feet aren't strong enough to stop you.

18) A constant torque is applied to a flywheel. Which of the following mechanical quantities will be constant?

A) rotational energy B) angular momentum C) rotational velocity D) rotational acceleration E) linear velocity of a particle on the rim

19) A flywheel is used to minimize changes in rotational velocity as the torque or the load changes. The rotational inertia of a flywheel should be chosen to be

A) anything—itdoesn't matter.

B) as small aspossible.

C) as large aspossible.

20) Three different bodies—a uniform sphere, a uniform disk, and a hoop—all have same radius and same mass. The body with the largest rotational inertia will be

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A) the sphere.

B) the disk.

C) the hoop.

D) None, as all have the same value of rotational inertia.

21) In using a long steel rod as a lever to move a large rock, where should the fulcrum be placed for a person to use the least amount of force to move the rock?

A) close to the person B) exactly halfway between the person and the rock C) anywhere in between; it makes no difference D) close to the rock

22)

The angular momentum of a rotating body is conserved when

A) no net torqueacts on the body.

B) no net force actson the body.

C) when the body has a constant rotational acceleration.

D) the shape of the body does not change.

23) When an ice skater twirling on the point of a skate draws her arms in she ends up whirling faster. This is because

A) rotational energy is conserved.

B) linear momentumis conserved.

C) angular momentumis conserved.

D) a net externaltorque acts on the skater.

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24) A gyroscope consists of a wheel mounted on an axle aligned along a north-south direction. The south end of the axle is suspended by a rope attached to the ceiling, and the north end is manually held at rest. The wheel is spinning rapidly, so that its angular momentum vector points north. Suddenly the north end is released. Since there is spin, the north end of the axle will begin to move

A) north.

B) east.

C) down.

D) west.

E) south.

25)

The rotational velocity of a 45 rev/min phonograph record in rad/s is approximately

A) 45 rad/s.

B) 4.7 rad/s.

C) 0.75 rad/s.

D) 283 rad/s.

E) 15.7 rad/s.

26) The armature (or spinning portion) of a motor is accelerated uniformly from rest to a rotational velocity of 1500 rev/min in 10 seconds. The rotational acceleration of the motor is A) 150 rad/s2.

B) 15.7 rad/s2.

C) 31.4 rad/s2.

D) 75 rad/s2.

E) zero.

27)

Which of the following is an appropriate unit for describing rotational acceleration?

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A) m/s2 B) rad/min C) rev/min D) rev/m/s E) rev/min2

28) A wheel is spinning on an axle. The linear velocity of a point on the rim is simply the product of the radius times the rotational velocity, as long as the rotational velocity is measured in units of

A) deg/s.

B) rev/min.

C) rad/s.

D) rev/s.

E) deg/min.

29)

Torque in the metric system is measured in units of

A) N. B) N s.

C) N rad.

D) N/m.

E) N m.

30) A top of rotational inertia 4.0 kg m2 receives a torque of 2.4 Nm from a physics professor. The rotational acceleration of the body will be A) 1.2 rev/s2.

B) 6.0 rad/s2.

C) 1.0 rad/s2.

D) 6.0 rev/s2.

E) 0.6 rad/s2.

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31) A merry-go-round, having a radius of 2.4 m, is set in motion starting from rest, by students applying a force of 600 N tangential to the rim of the wheel. After three seconds of torque, the students let go and measure the rotational speed: 1.50 rad/s. The rotational inertia of the merry-go-round is A) 900 kg m2.

B) 1440 kg m2.

C) 1800 kg m2.

D) 2880 kg m2.

E) 5000 kg m2.

32) A student plays on a see-saw with her experimental android robot, Robby. The student has a weight of 300 N and is seated 2.8 m from the axis of rotation. Robby balances her when he is seated 0.7 m from the axis. Robby's weight is

A) 1000 N. B) 500 N. C) 667 N. D) 725 N. E) 1200 N.

33) A solid disk and a hoop have different diameters but identical masses. Which one has a larger rotational inertia?

A) the solid disk B) the hoop C) It is impossible to know without knowing the diameters.

D) It is impossible to know without knowing the torques acting on the two objects.

34) A moving bicycle exhibits less stability when the angular momentum of the wheels is less, which means

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A) its forward speedis also slower.

B) its forward speed is faster.

C) the inverse of the forward speed equals the torque.

35)

If the net force on a body is zero, the net torque on the body is

A) always zero.

B) not necessarily zero.

C) certainly notzero.

36)

If the net torque on a body is zero, the net force on the body is

A) always zero.

B) not necessarily zero.

C) certainly not zero.

37) It is possible using the analogies between linear motion and rotational motion to write an expression for rotational kinetic energy. The formula for rotational kinetic energy (assuming τ is torque, α is rotational acceleration, I is rotational inertia, and ω is rotational velocity) is A) ½ τ α2.

B) ½ I α2.

C) ½ I ω2.

D) ½ τ ω2.

38)

If there is a net torque on a wheel, then

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A) there must be a net force on the wheel.

B) the wheel must have a nonzero rotational acceleration.

C) the wheel cannotbe spinning.

D) the angularmomentum of the wheel cannot change direction.

39)

If you push directly on the handle of a closed door and it does not swing open, then

A) its rotational inertia must be much larger than your torque.

B) the net torque onthe door must be zero.

C) the lever arm must be very small.

D) the angular momentum of the door is larger than your force.

40) sun

When a planet moves closer to the Sun in an elliptical orbit, its rotational inertia about the

A) does not changebecause the mass of the planet is constant.

B) gets smallerbecause its distance from the Sun is smaller.

C) gets smallerbecause the lever arm is shorter.

D) gets largerbecause the angular momentum must be conserved.

E) gets larger because the planet has more rotational acceleration.

41) A spinning wheel has an angular momentum that points toward the east. If an eastward force is applied to the edge of the wheel,

A) the angularmomentum of the wheel will change direction but not magnitude.

B) the angular momentum will get larger.

C) the angularmomentum will get smaller.

D) the angular momentum of the wheel will not change.

42) The stability of a bicycle is due to angular momentum of the wheels when the bicycle is moving forward. The stability is due to the net angular momentum vector, which

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A) points upward, perpendicular to the surface of Earth, thereby canceling the weight of the bicycle and rider.

B) points to the rider's left.

C) increases when the bicycle slows down due to conservation of energy.

D) is actually zero, since the back wheel cancels the angular momentum of the front wheel.

43) Even a little first-grader can stay up on a bicycle if he can get his bicycle moving fast enough because

A) the angular momentum of the wheels wants to stay horizontal, due to conservation of angular momentum.

B) the first-grader'sweight causes a torque too small to make the bicycle fall sideways whenmoving.

C) pedaling faster is easier once you are stable, and more pedaling increases net angular momentum.

D) All of these choices are correct

44)

In principle, a first-grader could measurably move the Earth if

A) she pushed herhardest on the Earth.

B) she had a long enough lever.

C) she ran herfastest opposite the spin of the Earth.

D) she was at the North Pole and had a bicycle wheel spinning opposite the spin of Earth.

45)

The advantage that a lever can give you is that

A) with a smallforce, you can move a large weight.

B) with a small lever, you can move a large weight.

C) with a large force, you can torque a large weight.

D) with a smalltorque, you can lift a large weight.

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46) Holding out your hands sideways helps you keep your balance along a narrow set of stepping-stones because

A) the arms outward balance your weight.

B) arms inward onlyadd to your weight.

C) with armsoutward, you've increased your total rotational inertia relative to the pivotpoint: your feet.

D) moving the armsoutward puts a counter-torque on the stepping-stones.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

47) Just as torque is the rotational analogue of force in linear motion, rotational inertia is the rotational analogue of in linear motion.

48) When a mechanic uses an extension arm on his wrench to loosen a stubborn nut, he is exerting additional torque because of an increase in the (two words) of the force.

49) The angular momentum of a rotating body is constant when the net the body is zero.

on

50) A merry-go-round is set into motion with a child on board. The rotational speed of the merry-go-round as the child moves inward along a radius.

51) If the net force on a body is zero the net torque not necessarily, cannot be) zero.

(is always, is

52) If a solid disk and a hoop are to have the same mass and rotational inertia, then the hoop must have a radius.

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53) If an object has an rotational acceleration larger than zero, its rotational be changing with time.

must

SECTION BREAK. Answer all the part questions.

54) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

54.1) The figure above shows two yo-yos that have the same mass and rotational inertia. The one on the right has a thicker axle than the one on the left. The torque produced by gravity is

A) larger for theyo-yo on the right.

B) larger for theyo-yo on the left.

C) the same for both yo-yos.

D) zero; there is no net torque on the yo-yos.

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Answer Key Test name: Chap 08_10e 1) D 2) C 3) A 4) A 5) D 6) B 7) C 8) D 9) B 10) B 11) B 12) D 13) A 14) C 15) B 16) D 17) A 18) D 19) C 20) C 21) D 22) A 23) C 24) D 25) B 26) B Version 1

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27) E 28) C 29) E 30) E 31) D 32) E 33) C 34) A 35) B 36) B 37) C 38) B 39) B 40) B 41) A 42) B 43) D 44) B 45) A 46) C 47) mass 48) lever arm 49) torque 50) increases 51) is not necessarily 52) smaller 53) velocity 54) Section Break 54.1) A

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Chapter 9: The Behavior of Fluids MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) Archimedes' Principle states that...

A) an object immersedin a fluid is buoyed up by a force equal to the weight of the displacedfluid.

B) the pressure of afluid is inversely proportional to the temperature of the fluid.

C) the pressure in afluid is directly related to the depth below the surface of the fluid.

D) the velocity of afluid is directly proportional to the pressure exerted on the fluid.

2) One morning you discover that a tire on your auto is in need of air. As you add air to the tire, which of the following statements is true?

A) The density of the air in the tire gets smaller.

B) The pressure of the air in the tire increases.

C) The number of atoms of air in the tire stays the same.

D) All of these statements are true.

3) A clown at the circus blows up a balloon with helium. This balloon will not float to the ceiling unless

A) the pressure ofthe helium inside the balloon is greater than the atmospheric pressure.

B) the weight of the balloon is less than the weight of the air displaced by the balloon.

C) the balloon andthe helium it contains weigh less than the air displaced by the balloon.

D) the pressure of the helium inside the balloon is less than the atmospheric pressure.

4)

A balloon inflated with helium is able to float toward the ceiling because

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A) the weight of the balloon is greater than the weight of the air displaced by the balloon.

B) the density of thegas inside the balloon is greater than the density of the atmosphere.

C) the pressure ofthe gas inside the balloon is less than the atmospheric pressure.

D) the pressure of the gas inside the balloon is greater than the atmospheric pressure.

E) the balloon andthe gas it contains weigh less than the air displaced by the balloon.

5)

A child is drinking a liquid with a straw. Which of the following statements is true?

A) The fluid is being pulled up into the straw.

B) Longer straws work better because the pressure is larger deeper down.

C) The pressure inside the straw depends on the viscosity of the liquid.

D) The pressure in the straw is reduced and the liquid is pushed upward by atmospheric pressure on the surface of the liquid.

6)

A sharp knife can more easily cut objects than can a dull knife because

A) a greater force can be applied with a sharp knife.

B) a greater pressure can be applied with a sharp knife.

C) dull knives cannot apply large forces.

D) sharp knives have edges that can fit between the molecules of the object.

7) The skinny tires of a 10-speed racing bicycle require more air pressure than the fat tires on an equally massive mountain bike because

A) the racing bike moves faster.

B) the racing biketouches the ground over a smaller area than the bike with fat tires.

C) the area ofcontact of the racing bike's tires is greater than that of the bike with fattires.

D) the racing bike exerts more force on the ground.

8) act?

An ant and an elephant are swimming in a lake. On which does the greater buoyant force

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A) The ant B) The elephant C) The same buoyant force acts on both.

D) Neither is floating, so no buoyant force is acting at all.

9) If you hold a light tissue in your hands and gently blow across its top, the tissue will rise slightly because

A) blowing across thetissue removes all of the air, and then the air below the tissue pushes thetissue up.

B) collisions of the moving air with the tissue cause it to rise.

C) the pressure ofmoving air is less than that of static air.

D) according to Archimedes' Principle, moving air exerts more buoyant force.

10)

A hot air balloon derives its lift from the property of fluids as stated by

A) Bernoulli's Principle.

B) Boyle's Law. C) Pascal'sPrinciple.

D) Archimedes'Principle.

11) If you sit in a boat near the edge of a river channel, you might notice the water moving more quickly on the side away from the shore (the channel side). If you are initially moving with the river, you will be pushed

A) into the channel because the water pressure is larger on the shore side.

B) into the channel by the turbulent flow of the water.

C) toward the shore because the water flow is laminar around the boat.

D) toward the shore because the water pressure is smaller on the shore side.

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12) An ice cube in a glass of water is pushed to the bottom of the glass and held there with a straw. Consequently, the buoyant force on the ice cube is now

A) exactly balancedby the force exerted only by the straw.

B) exactly balanced by the weight of the ice cube.

C) greater than whenthe cube was floating at the top.

D) the same as whenthe cube was floating at the top.

13) A boat floating in a large pool is loaded with wood blocks. The water level at the pool's edge is marked with a red line. The blocks are now thrown overboard and float outside the boat.

When the water becomes calm again,

A) the red line isslightly lower than the water level.

B) the red line isslightly higher than the water level.

C) the red line is still at the water level.

14) A boat floating in a large pool is loaded with solid iron bars. The water level at the pool's edge is marked with a red line. The iron is now thrown overboard. When the water becomes calm again,

A) the red line isslightly lower than the water level.

B) the red line isslightly higher than the water level.

C) the red line isstill at the water level.

15) An iceberg is floating in the ocean with 10% of its volume extending above the ocean's surface. What can you say about the iceberg?

A) Its weight is less than the water it displaces.

B) It displaces only 90% of its weight in water.

C) As it melts, a smaller fraction of its volume will extend above the surface.

D) Its density is close to but smaller than the density of water.

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16) If the atmospheric pressure is 15 lb/in2, what is the corresponding downward force on the top of a horizontal square area 5 inches on each side?

A) Zero B) 15 lbs.

C) 75 lbs.

D) 375 lbs.

17) It is observed that, as bubbles rise in a deep column of water, the diameter of the bubbles increases. This is best explained by

A) Bernoulli's Principle.

B) Boyle's Law. C) Archimedes'Principle.

D) Pascal's Principle.

18) Hot coffee is poured into a cylindrical container until it is nearly full. The container is immediately sealed by stretching a rubber balloon across the container mouth and tightly sealing the edges. Twenty minutes later, you observe that the still intact rubber seal

A) has bulged outward in the center of the mouth of the container.

B) is still flat across the entire mouth of the container.

C) has bulged outward only at the edges of the container mouth.

D) has sagged inward toward the coffee.

19) Three individuals stand with all of their weight on the heel of one foot: a man of weight 600 N and a heel area of 100 cm2, a child of weight 200 N and a heel area of 25 cm2, and woman of weight 450 N and a heel area of 2 cm2. The one exerting the least pressure on the ground is

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A) the man.

B) the child.

C) the woman.

D) All of these choices exert the same.

20) A silver dollar, a quarter, and a penny (these are in order of decreasing diameter) lie at the bottom of a wishing well filled with water. The coin experiencing the largest downward force on its top surface due to the water pressure is the A) silverdollar.

B) quarter.

C) penny.

D) All of these choices experience the same downward force.

21) A hydraulic jack is used to lift a load of weight 4000 N. The load-bearing cylinder has a radius of 4 cm, and the other piston has a radius of 1 cm. What force must be exerted on the smaller piston to support the load?

A) 100 N B) 250 N C) 1000 N D) 4000 N E) 16,000 N

22) A gas originally occupies a volume of 0.5 m3 at a pressure of 100 kPa. It is slowly allowed to expand until the volume is 2.5 m3. Assuming the temperature is kept constant, the final pressure will be

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A) 500 kPa. B) 100 kPa. C) 50 kPa. D) 20 kPa. E) 10 kPa.

23) In U.S. customary units, air pressure is measured in pounds per square inch. In the metric system, it is measured in Pascals, and one Pascal is equal to

A) one pound per square foot.

B) one newton persquare meter.

C) one newton per square centimeter.

D) one metric tonper hectare.

E) None of these choices are correct.

24) Suppose a little bubble of air has gotten into the top of a mercury barometer. If a person uses a barometer in the usual way, the reading of atmospheric pressure will be

A) correct.

B) higher than theactual value.

C) lower than theactual value.

25) The density of ice is about 900 kg/m3, and the density of water is about 1000 kg/m3. A cubic block of ice one meter on a side floats in water. Assuming that the lowest square face of the cube is horizontal, the height of the block above the water line is

A) 0.9 m.

B) 0.8 m.

C) 0.5 m.

D) 0.2 m.

E) 0.1 m.

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26) The density of aluminum is 2700 kg/m3. An aluminum block has a mass of 2.5 kg. The buoyant force exerted on this block when it is completely submerged in water of density 1000 kg/m3 is approximately

A) 0.0091 N. B) 0.93 N. C) 2.5 N. D) 9.1 N. E) 24.5 N.

27) One section of a pipe carrying water has a cross-sectional area of 16 cm2; in this section the water has flow velocity of 1.0 m/s. Another section of this pipe has a constricted crosssectional area of 4 cm2. If the flow is steady, what is the water velocity in the constricted section?

A) 4.0 m/s B) 2.0 m/s C) 1.0 m/s D) 0.50 m/s E) 0.25 m/s

28) How does the velocity of air moving over the top of the wing of an airplane in flight compare to the velocity of air moving under the wing?

A) The velocities are the same.

B) The velocity over the wing is greater.

C) The velocity under the wing is greater.

29) The glass in a window is 35 inches wide and 20 inches tall, and standard atmospheric pressure is 14.7 pounds per square inch. What net force would result on the glass if the air pressure outside the house were 1% lower than the air pressure inside?

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A) 103 pounds inward B) 103 pounds outward C) 10300 pounds inward D) 10300 pounds outward E) There would be no net force.

30) According to Bernoulli's equation, the pressure in a fluid will tend to decrease if its velocity increases. Assuming that a wind speed of 1 m/s causes a pressure drop of 0.645 Pa, what pressure drop is predicted by Bernoulli's equation for a wind speed of 5 m/s?

A) 1.29 Pa B) 1.94 Pa C) 3.325 Pa D) 16.125 Pa

31) Two cylindrical pipes both carry an ideal fluid (zero viscosity) in laminar flow. Pipe A has radius RA = 8 cm and flow velocity vA = 2 cm/s. Pipe B has radius RB = 4 cm and flow velocity vB = 4 cm/s. Compared to the rate of flow in pipe A, that in pipe B is

A) the same.

B) half aslarge.

C) twice aslarge.

D) It depends on the length of the pipe.

32) Some people say that, based on the arrangement of its molecules, glass should be considered a liquid. If we think of glass as a liquid, in which of these properties is it most unlike other common liquids?

A) weight B) density C) transparency D) viscosity

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33) A uniform wooden plank floats in a swimming pool. The plank weighs 100 pounds, and exactly 10% of its volume is above the waterline. The maximum weight of iron which could be suspended from underneath the plank without causing the whole combination to sink to the bottom of the pool is

A) exactly 10pounds.

B) somewhat morethan 10 pounds.

C) somewhat lessthan 10 pounds.

D) More information is needed.

34) A person wearing snowshoes can walk across a blanket of freshly fallen snow without sinking far into the snow because

A) the snowshoes reduce the force of the person on the snow.

B) the large area ofthe snowshoe concentrates the force of the person to a point smaller than thefoot.

C) snowshoes cover a larger area than a foot and so the pressure is reduced.

D) snowshoes push less dense snow out of the way so the person stands on more solid ice below.

35)

Atmospheric pressure decreases as one moves to higher elevations because

A) the force ofgravity is weaker on a mountain than at sea level.

B) it is much colder on a mountain than at sea level.

C) the air moves at higher speeds near mountains than over the oceans.

D) there is much less air above a mountain than above the oceans.

36) A block that has a density of 900 kg/m3 is placed in water (density 1000 kg/m3). The block will

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A) sink to the bottom.

B) sink until it isalmost, but not entirely, submerged.

C) sink until it isentirely submerged and then remain in place just below the surface.

D) sink just a little bit with most of the block above the water.

E) rest on the water with none of the block submerged.

37) Imagine a steel pipe that doesn't leak from the sides and is already filled with water.

Water enters at a rate of 2 kg/s but leaves at a rate of 1 kg/s. Which of the following is true?

A) The water pressure inside the tube rises as water is added.

B) The tube is narrower where the water enters than where it leaves.

C) The water flow must be laminar.

D) It is not possible for this situation to occur.

38) The best shape for an automobile to have is one that is streamlined both in the front and in the back. The reason for this is

A) to avoid unevenair flows that might push the vehicle sideways.

B) to improve fuel efficiency when driving in reverse.

C) to use the viscosity of the air to help propel the automobile forward.

D) to ensure the airflow remains laminar all the way around the vehicle.

39) A dump truck has a loosely tied canvas over its empty bed, which is full of still air. As the truck speeds down the highway, the canvas will tend to

A) get pushed onto the load.

B) billow outward from the load.

C) smooth out in a level, horizontal plane.

D) lay limply in a jumbled pile.

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40) One morning you discover that a tire on your auto is in need of air. This is visible: it has flattened significantly. Significant flattening indicates low air pressure

A) only if all tiresare equally flattened; otherwise it is just low atmospheric pressure.

B) because more ofthe tire's surface area is required to provide same amount of force.

C) and less weight.

D) and highertemperature.

41) Storm winds blowing at high speed over a roof can destroy the roof of a closed-up house because of Bernoulli's Principle. What happens is

A) the roof is pushed inward and collapses.

B) the wind insidethe house blows out the roof from the inside.

C) the higherpressure inside lifts the roof off the walls.

D) friction rips up the roof and blows it apart.

42) A baseball pitcher throws a curveball, and Bernoulli's Principle gives a fair description of why it takes such a drastic curve. If that pitcher could throw the exact same pitch on the Moon, then

A) it would curve more drastically, because gravity is so much weaker on the Moon.

B) it would curvemore drastically, because there is no counterforce from air pressure on theMoon.

C) it would curve but not as much as on Earth, since the Moon's gravity is so weak.

D) it would notcurve at all, because the Moon has no atmosphere.

43)

Which of the following statements is true?

A) A floating ocean liner will displace its own volume of water.

B) A submerged submarine will displace its own weight of water.

C) A floating ocean liner will displace its own weight of water.

D) None of these statements are true.

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44) Even though your car weighs several thousand pounds, it can easily be raised above your head by a pneumatic lift at the service station by a small motor pumping fluid through a pipe.

This an illustration of

A) Pascal'sPrinciple.

B) Archimedes'Principle.

C) Bernoulli'sLaw. D) Newton's 3rd Law.

45) A sealed hot air balloon is capable of rising to high altitudes when it is initially released.

As the air in the balloon cools, however, it eventually comes back down to the ground because

A) what goes up mustcome down.

B) objects heavierthan air can only fly through the air with the help of a motor.

C) the object comesdown when the air in it eventually leaks out.

D) objects can onlyfloat in a fluid if their density is less than that of the fluid.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

46) Suppose you have a helium-filled weather balloon above the house. As a storm leaves, the atmospheric pressure rises. Assuming the air temperature is the same, the volume of the balloon will .

47)

Pascal's Principle states that an increase of pressure on an enclosed fluid is transmitted throughout the fluid.

48) If a barometer were to be made using water as the liquid instead of mercury, the length of the barometer tube for water would be than the tube for a standard mercury barometer.

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49) A piece of soft wood floats in water with half of its volume submerged. If it is placed in mercury which has a density about 13.6 times that of water, it will float (higher, lower, the same) compared with floating in water.

50)

The operation of hydraulic brakes in a car is based upon

Principle.

51) Other things (density, altitude, temperature) being equal, a moving gas exerts less pressure than a stationary gas. This is predicted by (2 words).

52) A gas initially is at a pressure of 35 kPa. If its volume is halved while the absolute temperature is kept constant the new pressure will be kPa.

53)

A fluid that flows very slowly compared to water has a high

54)

When the flow of air over an object is laminar,

.

drag is created on the object.

55) The carburetor of a car is a pipe with a constriction. Compared to the velocity of flow of a mixture of air and gasoline in the main pipe, the velocity in the constriction will be .

The pressure in the constriction will be than the pressure in the main pipe.

56) Suppose you have 10 helium-filled party balloons tied to a digital camera, so you can take photos of the core of a storm. With 10 balloons the camera will slowly but surely rise. As a storm approaches the atmospheric pressure drops. Assuming the air temperature and density are the same, the volume of each balloon will increase. When you let go, the speed of ascent will be .

57)

Aerodynamic lift results from

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Answer Key Test name: Chap 09_10e 1) A 2) B 3) C 4) E 5) D 6) B 7) B 8) B 9) C 10) D 11) A 12) C 13) C 14) B 15) D 16) D 17) B 18) D 19) A 20) A 21) B 22) D 23) B 24) C 25) E 26) D Version 1

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27) A 28) B 29) B 30) D 31) B 32) D 33) B 34) C 35) D 36) B 37) D 38) D 39) B 40) B 41) C 42) D 43) C 44) A 45) D 46) decrease 47) uniformly 48) longer 49) higher 50) Pascal's 51) Bernoulli's equation 52) 70 53) viscosity 54) less 55) greater / less 56) faster Version 1

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57) Bernoulli

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CHAPTER 10 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) The temperature of a sample of a substance is a way to gauge

A) the averagemomentum of the fastest 50% of the molecules in the sample.

B) the kinetic energy of the fastest moving molecule in the sample.

C) the average momentum of the molecules in a sample.

D) the average kineticenergy of the molecules in that sample.

2)

After I dip a cup of water from the ocean, I can conclude that

A) the temperatures are the same but the water in the cup has more energy.

B) the temperature ofthe water in the cup is the same as the temperature of the water in theocean.

C) the ocean temperature is higher because it has more molecules in it.

D) the ocean temperature is higher because it never loses its heat.

3)

Heat is a form of energy, and it has long been known that heat energy will naturally flow

A) from hot to coldobjects.

B) from cold to hotobjects.

C) from solids to liquids, but only when the solid is melting.

D) from liquids to solids, except when the solid is melting.

4) The amount of heat is often measured in calories. If I add 1 calorie of heat energy to 1 gram of water, the temperature of the water will

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A) decrease by1°F. B) decrease by1°C. C) stay the same, since water has a very high specific heat.

D) increase by1°F. E) increase by1°C.

5) On a cold winter's morning you awake and step out of bed. One foot is on the tile floor and the other is on a rug on the floor. Which statement is true?

A) The tile feels colder because it is smoother than the rug.

B) The tile feels colder because it is connected to the cold ground outside.

C) The tile feels colder because it conducts heat more rapidly away from your foot.

D) The tile feels colder because it cannot absorb water like the rug can.

6) Two identical objects, one light colored and the other dark colored, are at the same elevated temperature, 50°C. You now place them in a dark, much cooler room. Which object will reach the room's temperature first?

A) the light colored object B) the dark colored object C) Both reach room temperature at same time.

D) As strange as it seems, neither object will ever reach room temperature because energy conservation prevents the loss of energy.

7) Two identical objects, one light colored and the other dark colored, are at the same cool temperature. Then, you place them outside, on a warm day, in direct sunlight. Which object will warm up faster?

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A) the dark one B) the light one C) Both warm up at the same rate.

D) As strange as it seems, neither object will ever warm up because energy conservation prevents the addition of energy.

8)

The lowest possible temperature a body can approach is called

A) "mighty" cold.

B) absolute zero.

C) triple point.

D) criticaltemperature.

E) triple absolutezero.

9)

Water freezes at 273 on the

scale.

A) Fahrenheit B) Celsius C) Rankin D) Kelvin E) Vernier

10)

When the temperature of the air in a balloon is raised, the volume of the balloon

A) increases.

B) stays the same.

C) decreases.

11) Objects A and B are at the same temperature. Object A now has its temperature increased by one Fahrenheit degree, while B has its temperature increased by one Kelvin degree. Which object now has higher temperature?

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A) object A B) object B C) Both have the same temperature.

D) It is impossible to tell from this data.

12)

Which process does not transfer heat energy between objects?

A) convection B) radiation C) reflection D) conduction

13) A mixture consists of 70 g of ice and 60 g of liquid water, both at 0°C. (The latent heat of fusion of water is 80 cal/g and the specific heat capacity of water is 1.0 cal/g C°.) The amount of heat that must be added to melt all of the ice is about

A) 4000 cal.

B) 5600 cal.

C) 21,600 cal.

D) 32,400 cal.

14) While studying for this quiz you realize that you still have 100 g of lukewarm coffee at 40°C left in a paper cup. When you pour 20 g of boiling water into the cup, the temperature of the resulting coffee-like mixture will be now

A) 50°C. B) 60°C. C) 67°C. D) 70°C. E) 80°C.

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15) A box of graham crackers is labeled "120 Calories per serving." Assuming this means 120 kcal, and recalling that 4.16 J = 1 cal, the energy of a serving of the graham crackers is about A) 5 × 105 J. B) 5 × 104 J. C) 4.2 × 103 J. D) 120 J.

16) The temperature of 100 g of water is to be raised from 10°C to 90°C. (The specific heat capacity of water is 1.0 cal/g C°) The energy needed to do this is about A) 1 ×103 cal.

B) 5 ×103 cal.

C) 6 ×103 cal.

D) 8 ×103 cal.

E) 5.4 ×104 cal.

17)

Which of the following temperatures is the lowest?

A) 0°C B) 0°F C) 263 K D) All of these choices are the same.

18)

Absolute zero is the temperature

A) on the coldest day recorded at Nome, Alaska.

B) at which an idealgas would exert zero pressure.

C) of the freezingpoint of water.

D) of the boiling point of liquid helium.

E) of the freezing point of mercury.

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19) Four samples of steel, lead, alcohol, and glass all have the same mass and are all initially at 20°C. After 100 calories of heat are added to each sample, the final temperatures are 38.2°C for the steel, 85.6°C for the lead, 23.4°C for the alcohol, and 30°C for the glass. Which of these four materials has the largest specific heat capacity?

A) the steel B) the lead C) the alcohol D) the glass E) All of these choices have the same heat capacity, since all absorbed 100 cal of heat.

20) On a cold day, a metal fence post feels colder to the touch than a tree. This sensation of different temperatures is explained by the fact that

A) the temperature of the tree is higher.

B) the specific heatcapacity of the metal is higher.

C) the specific heatcapacity of the wood in the tree is higher.

D) the thermalconductivity of the metal is higher.

E) the thermalconductivity of the wood in the tree is higher.

21)

The term heat in physics is

A) equivalent to temperature.

B) equivalent to internal energy.

C) energytransferred to a body because of a difference in temperature.

D) any energytransferred to a body that raises the temperature of the body.

E) the same as work.

22) During the course of a demonstration the professor is called away. When he returns he finds a beaker of water that was at room temperature is now at a slightly higher temperature.

There is a stirring rod on the desk and a cigarette lighter. The professor can assume that the temperature increase is due to

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A) heat added to the system.

B) mechanical work done on the system.

C) either heat added or mechanical work done.

23) Heat flows into a gas in a piston and the gas performs some work on its surroundings.

The amount of work done is less than the heat added. In this situation,

A) the internal energy of the gas decreased.

B) the internalenergy of the gas increased.

C) the internalenergy of the gas did not change.

D) the gas experienced a phase change.

E) energy is not conserved and so it cannot happen.

24) Compare the internal energy of one gram of steam to that of one gram of water if both are at 100°C.

A) The internal energy of the steam will be higher.

B) The internal energy of the water and steam are the same.

C) The internal energy of the water will be higher.

25) An ice cube of mass 100 g and at 0°C is dropped into a Styrofoam cup containing 200 g of water at 25°C. (The latent heat of fusion of water is 80 cal/g and the specific heat capacity of water is 1.0 cal/g C°.) Assuming the cup does not exchange any heat with the outside, what will happen?

A) All of the water will freeze.

B) Some of the water will freeze.

C) Nothing will happen.

D) Some of the ice will melt.

E) All of the ice will melt.

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26)

Heat is added to an ideal gas and the gas expands. In such a process the temperature

A) must always increase.

B) must alwaysdecrease.

C) will remain thesame if the work done equals the heat added.

D) will remain the same if the work done is less than the heat added.

E) will remain the same if the work done exceeds the heat added.

27) Hot cider is poured into a metal cup. Shortly thereafter the handle of the cup becomes hot. This is due to the process of

A) radiation.

B) convection.

C) conduction.

D) It will remain the same if the work done exceeds the heat added.

28) A physics student has to make a choice in the color of paint to put on her geosynchronous communication satellite, MYSAT1. Considering most of its orbit is in sunlight, the decision of a light versus dark color paint will depend on which concept below?

A) A light paint would be better for keeping the satellite cool in sunlight.

B) A dark paint would be better for keeping the satellite cool in sunlight.

C) A light paint would be better in the sunlight and in Earth's shadow for preventing overheating.

D) A dark paint would overheat the satellite when it passes through Earth's shadow but not in sunlight.

29)

Which of the following units is not an energy unit?

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A) Joule B) Kilowatt-hour C) Horsepower D) Kilocalorie E) Calorie

30) The temperature of a 50 g sample of aluminum is raised from 20oC to 60oC when 440 cal of heat are added. The specific heat capacity of the aluminum is

A) not calculable from this data.

B) 0.11 cal/g Co. C) 15.4 cal/g C°.

D) 0.91 cal/gC°.

E) 0.22 cal/gC°.

31) If you stand near a large fire, your face will be cooler if you place your hand between your face and the fire. Your hand is preventing heat flow by

A) latent heat.

B) conduction.

C) convection.

D) radiation.

32)

Whenever a gas is compressed,

A) work must be done on the gas.

B) its internal energy must get smaller.

C) heat must leavethe gas.

D) the temperature of the gas must get smaller.

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33) After working hard outside on a hot summer day, placing a towel soaked in cold water on your head can feel very good. The reason the towel feels cold to you is that

A) low temperature heat from the towel conducts to your head, lowering your temperature.

B) cold air radiatesfrom the towel to your head.

C) cold air from the towel convects to your head.

D) heat conducts fromyour head to the towel, lowering your temperature.

34) You lose your left sandal during a hot afternoon at the beach. Thus, you must hike back to your vehicle with one bare foot across the burning sand. Why does the bare foot get so much hotter?

A) The sandal insulates the right foot from the hot sand.

B) The sandal conducts heat away from your right foot and into the sand.

C) The sandal is in the shadow of your foot, but the sand is not.

D) Heat flows from your right foot into your left foot and then out into the sand, thus cooling off your right foot.

35)

Which object is hotter?

A) Object 1 at T = 0° C B) Object 2 at T = 0° F C) Object 3 at T = 0 K

36) The air at the beach is the same temperature everywhere, but you feel cooler under a beach umbrella because

A) the sandunderneath you cools off more rapidly than the water vapor in the air.

B) the umbrella gets hot, which thereby cools off the air underneath it.

C) solar radiationis not heating up your skin.

D) a convection cell forms under the umbrella, thereby cooling you off.

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37)

When you apply an alcohol swab to your skin, it feels cool because

A) your skin transfers a bit of heat to the liquid alcohol and the alcohol evaporates.

B) the density of alcohol is less than 1 g per cm3.

C) germs are destroyed by the alcohol, and they give off cold heat as they die.

D) of nothing—it is an illusion, because evaporating alcohol is actually hotter than liquid alcohol.

38) An ice cube is floating in a glass of water with the water level just reaching the top of the glass. If the temperature in the surrounding area is above freezing, the ice cube will melt. When it does,

A) water will beginto spill over the top of the glass.

B) the water levelin the glass will remain unchanged as the ice continues to melt.

C) the water levelin the glass will begin to go down.

D) it is impossibleto tell what the water level will do from the information given.

39) Water in a dish is set on a table in an initially empty closed room and begins to evaporate.

The temperature of the water will A) begin toincrease.

B) begin todecrease.

C) remain thesame.

D) not be able to bepredicted based on the information given.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

40) During a phase change the temperature of a system will be as heat is added.

41)

The first law of thermodynamics is an extension of the principle of conservation of that we first met in mechanics.

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42)

Heat will not be transferred between two bodies that are at the same .

43)

The transfer of heat from a furnace to the house through ducts is by the process of .

44) A student uses a thermometer calibrated in Kelvin units. A temperature change of 20 K is equivalent to a change of how many degrees on the Celsius scale? .

45) The internal energy of a system such as helium gas can be identified as the total mechanical energy of the .

46) When water boils, the primary form of heat flow in the water is (conduction, convection, radiation).

47)

When heat is added to a solid object, the

of the object must increase.

48) The process in which some substances may remain in a liquid state even though their temperature may dip below the freezing point is known as

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Answer Key Test name: Chap 10_10e 1) D 2) B 3) A 4) E 5) C 6) B 7) A 8) B 9) D 10) A 11) B 12) C 13) B 14) A 15) A 16) D 17) B 18) B 19) C 20) D 21) C 22) C 23) B 24) A 25) D 26) C Version 1

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27) C 28) A 29) C 30) E 31) D 32) A 33) D 34) A 35) A 36) C 37) A 38) B 39) B 40) constant 41) energy 42) temperature 43) convection 44) 20 45) atoms 46) convection 47) temperature 48) supercooling

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CHAPTER 11 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) The second law of thermodynamics says that the total amount of entropy, or randomness, in the universe cannot decrease. However, we see all around us objects that become more ordered—for example, the development of a biological organism or water that freezes. The decrease in entropy, or randomness, in such cases does not violate the second law because

A) energy must beremoved.

B) energy must be added.

C) there is always agreater increase in entropy somewhere else.

D) water and living things do not have entropy.

2) Why couldn't you use an electric motor to turn an electrical generator that in turn provides the electrical energy for the motor?

A) No energy converter is 100% efficient.

B) Yes, you can do this.

C) Motors require AC and generators produce DC.

3) Shown are four figures that represent the heat flow in a heat engine. The thickness of the arrows represents the amount of heat flow. TH is the high-temperature reservoir, TC is the lowtemperature reservoir, QH is heat to/from TH, QC is heat to/from TC, and W is work. Which figure best represents a real heat engine?

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A) A B) B C) C D) D

4)

Energy added to a cyclical heat engine

A) is completely converted to external work.

B) is converted towork and to waste heat.

C) is used to generate work that is greater than the added energy.

D) is converted toincreased internal energy in the engine plus external work.

5)

The primary function of any heat engine is to

A) create a large amount of energy from a small amount of heat.

B) create heat.

C) convert heat intowork.

D) destroy energy andreplace it with work.

6)

The work performed by a heat engine

A) equals the heat energy exhausted from the engine.

B) equals the heat energy entering the engine.

C) equals the change in the internal energy of the engine.

D) equals the net heat flow into the engine.

7)

The change in internal energy during one complete cycle of a heat engine

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A) equals zero.

B) equals the netheat flow into the engine.

C) equals the heat energy exhausted from the engine.

D) equals the heat energy entering the engine.

8)

One important feature of the Carnot cycle is that it

A) maximizes the entropy of a heat engine operating between two temperatures.

B) specifies the operating temperatures of any heat engine.

C) converts all ofthe heat flowing into an engine to work.

D) predicts themaximum efficiency of a heat engine operating between two temperatures.

9)

The efficiency of an engine can be defined as the

A) ratio of work doneto energy input.

B) total amount ofwork performed.

C) ratio of work doneto energy exhausted.

D) ratio of heat exhausted to heat intake.

10)

If a Carnot heat engine is run in reverse, it becomes

A) a heat engine with the smallest possible efficiency.

B) an engine that hasa negative efficiency.

C) arefrigerator.

D) nothing. It can'tbe run in reverse because to do so would violate the second law ofthermodynamics.

11)

A correct statement of the Second Law of Thermodynamics is

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A) the random motion of gas molecules will be decreased if energy is added to a gas.

B) there is no process that can make heat flow from a cold object to a hot object.

C) no heat engine can have an efficiency greater than 30%.

D) heat will not flow spontaneously from a cold object to a hot object.

12)

The amount of disorder in a system is called

A) density.

B) entropy.

C) temperature onthe Kelvin scale.

D) pressure.

13)

The overall direction of change in the universe is toward

A) a state of increased mass in the universe.

B) increased energy content of the universe.

C) a state ofincreased organization.

D) a state ofgreater disorder.

14) An ideal heat engine is operating between high and low temperature reservoirs. Suppose that now the low temperature reservoir has its temperature lowered, but no other changes are made. This temperature change affects the engine efficiency in which of the following ways?

A) The efficiency decreases.

B) The efficiency is unchanged.

C) The efficiency increases.

D) There is now no way to calculate the efficiency.

15) Some power plants extract energy from the warm ocean currents. A major disadvantage to these power plants is that

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A) the efficiency isquite low.

B) there is no low temperature reservoir.

C) the amount of heat released to the environment is unacceptable.

D) the cost of warmocean water is quite high.

16)

In one cycle of any heat engine

A) the net heat flow is zero.

B) the internalenergy of the engine does not change.

C) more heat flowsfrom the engine than enters the engine.

D) the net work done is larger than the heat exhausted.

17)

A Carnot engine is

A) equivalent to the gasoline internal combustion engine.

B) currently in production for the new generation of imported cars.

C) a theoretical engine having the highest possible efficiency for the temperatures involved.

D) one that would violate the second law of thermodynamics.

18)

A Carnot engine

A) consists of only isothermal processes.

B) consists of only processes which do not involve heat flow.

C) consists ofconstant temperature and constant volume processes.

D) absorbs heat at asingle high temperature and rejects heat at a single low temperature.

E) consists of zero heat flow and constant pressure processes.

19) A Carnot engine operating between reservoirs at 500°C and 300°C would have an efficiency of approximately

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A) 0.11.

B) 0.26.

C) 0.50.

D) 0.67.

E) 0.74.

20) A heat engine having an efficiency of 0.20 takes in 2000 J of energy from the hot reservoir in one cycle. In the same time, how much work will it perform?

A) 0 J B) 400 J C) 1000 J D) 120 J E) 33,333 J

21) A heat engine takes in 500 J of energy from the hot reservoir in one cycle while performing 100 J of work. The amount of heat transferred to the cold reservoir in the same time is

A) 500 J. B) 400 J. C) 300 J. D) 200 J. E) zero.

22) A heat pump is capable of delivering more energy to the home than goes into the operation of the pump itself, when conditions are favorable. Which of the following statements is correct?

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A) A heat pump transfers some energy from the outdoors.

B) A heat pump violates the second law of thermodynamics.

C) A heat pump violates the first law of thermodynamics.

D) A heat pump, like the Carnot engine, is a theoretical device that is not useful in practice.

E) A heat pump is more efficient when the outside temperature is colder.

23) A refrigerator transfers heat from a colder body to a hotter body while energy is used to operate the device. This is

A) allowed only if the internal energy of the refrigerator increases.

B) consistent with Clausius's statement of the second law.

C) possible if entropy of the contents of the refrigerator increases.

D) impossible unless the refrigerator uses a Carnot cycle.

24)

Entropy is

A) another term for heat.

B) a quantity that is conserved in any thermal process.

C) a quantity thatincreases as the disorder of a system increases.

D) something thatnever locally decreases in any process.

25) An inventor has created a heat engine that extracts energy from geothermal hotspots and geysers like Old Faithful at Yellowstone National Park. She claims to turn all of the geothermal energy into work. Such a device is

A) a violation of the first law of thermodynamics.

B) consistent withClausius's statement of the second law of thermodynamics.

C) only possible for a Carnot cycle.

D) a violation ofKelvin's statement of the second law of thermodynamics.

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26) A heat engine that would take in 1000 J of heat from a reservoir at 500 K and exhaust 500 J to a reservoir at 300 K, converting the other 500 J of heat to work, is

A) thermodynamicallypossible.

B) possible only for a Carnot cycle.

C) notthermodynamically possible.

27)

Which of these is characteristic of an ideal (Carnot) heat engine?

A) It does not create waste heat.

B) It cannot be used to cool a house.

C) It creates more energy than it consumes.

D) It causes no increase in entropy.

If, for an ideal heat engine, QH , QC, and W are, respectively, the heat absorbed, the heat 28) exhausted, and the work done per cycle, which of these is true?

A) QH cannot be more than W. B) QC cannot be more than QH. C) W cannot be more than QC. D) QH cannot be more than QC.

29) Some people claim that the theory of evolution violates the second law of thermodynamics, since that theory holds that order develops out of disorder, corresponding to a decrease in entropy. This claim

A) is incorrect; thesecond law says only that the total entropy in a closed system increases.

B) is correct,thereby disproving the theory evolution.

C) if incorrect, would mean that the theory of evolution must be true.

D) None of these choices are correct.

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30) Suppose 150 Joules of work is done on a system and that 300 Joules of heat are delivered to the system. Which of these is predicted by the first law of thermodynamics?

A) The internal energy U of the system increases by 450 J, since Q = +300 J and W = 150 J. B) The internal energy U of the system decreases by 150 J, since Q = -300 J and W = +150 J. C) The internal energy U of the system increases by 150 J, since Q = +300 J and W = +150 J. D) The internal energy U of the system does not change.

31)

Which of these is impossible, by the second law of thermodynamics?

A) using heat exhausted by a refrigerator to cook a meal B) an engine that generates electricity by extracting heat from cold water and dumping waste heat to warmer air C) water evaporating from a lake and then condensing to form clouds D) a single match carelessly discarded causes 1500 acres of woodland to burn

32) It is impossible to construct an engine that is more than 100% efficient. The physical law covering this case is

A) the zeroth law of thermodynamics.

B) the first law of thermodynamics.

C) Clausius's statement of the second law of thermodynamics.

D) Kelvin's statement of the second law of thermodynamics.

E) the third law of thermodynamics.

33)

The efficiency of a Carnot engine would be increased if

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A) the high temperature were lowered by 100°C. B) the low temperature were raised by 100°C. C) the high and lowtemperatures were both raised by 100°C. D) the high and lowtemperatures were both lowered by 100°C.

34)

An engine that decreases the total entropy in the universe is

A) a refrigerator.

B) a Carnot engine.

C) a heat pump.

D) impossible.

35)

A reversible engine is one that

A) does no net work.

B) causes noincrease in net entropy.

C) generates no netheat.

D) acts as a refrigerator.

36)

What method does not directly use heat for generating electricity?

A) nuclear power plants B) hydroelectric dams C) natural gas D) geothermal power E) All of these methods use heat to generate electricity.

37) Electric heaters can operate at efficiencies very close to 100%. This does not contradict the fact that Carnot engines are the most efficient heat engines because

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A) electric heaters have very low temperature exhaust.

B) electric heaters reduce the total entropy of a room.

C) Carnot engines cannot be used to heat things.

D) electric heaters are not heat engines.

38) An amount of water forms a single hexagonally symmetric snowflake. Elsewhere the same amount of water is a droplet of liquid water. Which state has higher entropy?

A) Their entropy levels are the same, since they are actually the same amount of H2O, just different phases.

B) The droplet of liquid water, since it is more unruly and can adopt almost any shape.

C) The solid water, since it has a tight restriction to hexagonal symmetry.

39) Entropy and temperature measure different properties of a sample of a substance, because temperature gauges average kinetic energy of molecules or atoms, but

A) entropy is the inverse of temperature, due to conservation of momentum.

B) low entropy substances cannot have a temperature.

C) entropy of an isolated system cannot decrease.

D) entropy measures disorderliness or unruliness.

40)

It is an advantage for an automobile engine to run at a high temperature because

A) its efficiency ishigher, since the temperature difference is what dictates efficiency.

B) gasoline onlyignites under high temperature conditions.

C) a high operating temperature cools off the fuel before ignition.

D) it allows the use of lighter engine components made from aluminum.

41)

Nuclear power stations have thermal electric generation that

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A) converts uranium into natural gas, and then ignites the natural gas.

B) converts thenucleus of uranium atoms into electrons.

C) generates heatfirst, then steam which drives a spinning turbine connected to a generator.

D) are reversible heat engines.

42) Oceanic thermal generation operates from a relatively inexhaustible source of energy in the oceans that have heat energy from

A) the energy insunlight.

B) subatomic heat.

C) the decay ofcarbon in the rock formations underlying Earth's oceans.

D) carbon dioxide in the ozone layer.

43)

An example of a reversible process would be

A) firing a bullet from a gun.

B) quickly pouring hot water into colder water.

C) striking a match.

D) slowly pouring hot water into cold while allowing the beakers to achieve ambient temperature levels.

E) None of these choices are correct.

44) According to the kinetic theory of gases, the molecules in the air in a particular room must have some kinetic energy which depends on the temperature in the room. In order to extract this energy to do mechanical work I would need for the object receiving this energy to be at a much colder temperature. This is best explained by

A) conservation of energy.

B) the law of gravity.

C) the Second Law of Thermodynamics.

D) Newton's laws of motion.

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45)

The actual source of wind energy is

A) solar energy.

B) the daily rotation of the Earth on its axis.

C) the tides.

D) the lunar cycle.

46) The efficiency of a Carnot engine is 46%. What will be the temperature of the cold reservoir if the temperature of the hot reservoir is given as 510°C.

A) 150°C B) 423°C C) 275°C D) 237°C

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

47) A process carried out at constant temperature is known as a(n) process.

48) Heat is extracted from a hot reservoir during a(n) Carnot cycle.

49)

expansion in a

In an ideal reversible process such as a Carnot cycle the entropy of the universe (increases, decreases, is unchanged).

50) A refrigerator that would transfer heat from a cold body to a hotter body without work being done would violate statement of the second law of thermodynamics.

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51) In any process, the total remains constant.

52)

A refrigerator is actually a

in all parts of the universe increases or

(two words) running in reverse.

53) When one kilogram of ice at 0°C is converted to the same amount of water at 0°C by adding heat, the change in entropy is (positive, negative, zero).

54) will

If a refrigerator door is left open while the refrigerator is on, the temperature of a house (increase, decrease, not change).

55) An automobile engine operates between a high temperature set by the burning of gasoline and the low temperature of the outside environment. If the engine has been running for some time, the engine is most efficient on (hot or cold) days.

56) A Carnot heat engine could have an efficiency of 100% only if the temperature of the exhaust were at .

57) A heat engine that converts all the heat taken in from a single temperature source to work would be in violation of what natural law? (more than one word)

58)

A good conductor of electricity is generally a good conductor of heat. True or False?

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Answer Key Test name: Chap 11_10e 1) C 2) A 3) B 4) B 5) C 6) D 7) A 8) D 9) A 10) C 11) D 12) B 13) D 14) C 15) A 16) B 17) C 18) D 19) B 20) B 21) B 22) A 23) B 24) C 25) D 26) C Version 1

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27) D 28) B 29) A 30) A 31) B 32) B 33) D 34) D 35) B 36) B 37) D 38) B 39) D 40) A 41) C 42) A 43) D 44) C 45) A 46) A The temperature of the cold reservoir will be 150°C. 47) isothermal 48) isothermal 49) is unchanged 50) Clausius's 51) entropy 52) heat engine 53) positive 54) increase 55) cold Version 1

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56) 0 K 57) second law of thermodynamics 58) True

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CHAPTER 12 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) An electron situated near another electron would feel

A) an attractivemagnetic force.

B) an attractive electrical force.

C) a repulsive magnetic force.

D) a repulsiveelectrical force.

E) no forces from the other electron.

2) Consider a proton and an electron placed near one another with no other objects close by.

They would

A) accelerate away from each other.

B) accelerate towardeach other.

C) remainmotionless.

D) be pulled together at constant speed.

E) move away from each other at constant speed.

3) Compared to the magnitude of the charge on a proton, the magnitude of the electrical charge carried by an electron is

A) exactly thesame.

B) about thesame.

C) only 1/2 as large.

D) only 1/3 as large.

4)

The charge of a proton is due to

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A) rapid spinning ofthe proton.

B) periodic pulsations of the surface of the proton.

C) the high density of the proton.

D) reasons physicistsare not yet quite sure of, but they explain charge as a property of theproton.

5) Two equal positive charges are near each other. If we increase the amount of charge on just one of them, then

A) the electric fieldpoints toward the larger charge.

B) the strength ofthe electrical force on both decreases.

C) the electric fieldat the position of the smaller charge increases.

D) the larger chargefeels a stronger electrical force and the other a weaker electrical force.

6)

A typical, neutrally charged atom has

A) just as many electrons as protons.

B) no neutrons in the nucleus.

C) more protons than electrons.

D) as many electrons as protons and neutrons combined.

E) at least 1 neutron.

7) A strip of fur is rubbed against a hard rubber rod. The rod thereby acquires a negative charge because

A) electrons from theair molecules are transferred to the rod.

B) frictional forcescreate electrons.

C) rubbing causedelectrons to move from the fur to the rod.

D) friction causedprotons to be removed from the rod.

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8)

The electrical force between two charged objects depends on

A) the number of electrons in the objects.

B) the total number of protons in both objects.

C) the sum of the netcharges on the objects.

D) the product of thenet charge on each of the two objects.

E) just the magnitude of the largest charge.

9)

The electrical force between any two charged objects is

A) always attractive.

B) always repulsive.

C) dependent on thesign of the charge on each object.

D) always balanced bythe action-reaction forces.

10)

Our model for explaining the electrical interaction between charged objects

A) postulates that anelectric field surrounds each charged object.

B) makes sense onlyat very high speeds.

C) depends on theexistence of three kinds of charge.

D) depends very strongly on the mass of the two objects.

11) If the distance between two spherical charged objects decreases by a factor of two, then the electrical force between the objects

A) decreases by a factor of four.

B) increases by afactor of four.

C) is half asbig.

D) doubles.

E) does notchange.

12)

The electric field created by a moving negative charge

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A) points away fromthe charge.

B) describesconcentric circles about the direction of motion.

C) points in thedirection of motion.

D) points in thedirection opposite to the velocity.

E) points toward thecharge.

13)

If the potential at point A is one volt it means that

A) a charge at A haspotential energy one joule for each coulomb of charge.

B) an object at Ahas charge equal to one coulomb.

C) an electron at Acan perform one Joule of work.

D) there is a smallbattery present.

14)

A metallic object has a net charge on it. For steady state conditions, the excess charge is

A) spread evenly throughout the object.

B) in the center of the object.

C) only on the surface.

D) on the bottom of the object.

E) on the north side of the object.

15)

After a glass rod is rubbed with a nylon cloth

A) both the rod andcloth will have a positive charge.

B) the rod will havea positive charge and the cloth negative.

C) the rod will have a negative charge and the cloth positive.

D) both the rod and cloth will have a negative charge.

E) the rod will have a negative charge and the cloth will be neutral.

16) A rubber rod is rubbed with fur, so that the fur becomes positive. The rod is then used to charge an electroscope. The charge on the electroscope will be

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A) negative ifcharged by polarization.

B) positive ifcharged by contact.

C) negative ifcharged by induction.

D) positive ifcharged by induction.

E) neutral.

17) A positively charged rod is brought close to an uncharged electroscope. While the rod is close, one's finger touches the far side of the metal ball on the electroscope. The finger is removed and then the rod is taken away. The electroscope is

A) negativelycharged.

B) positivelycharged.

C) uncharged.

18) A negatively charged rod is brought close to an uncharged electroscope. While the rod is close one's finger touches the far side of the metal ball on the electroscope. After the charged rod has been removed the finger is removed. The electroscope is

A) negativelycharged.

B) positivelycharged.

C) uncharged.

19)

Comparing the electrostatic force and the gravitational force we can say that

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A) both have the same dependence on distance, both involve attraction and repulsion, but the gravitational force is stronger.

B) both have the same dependence on distance, both involve attraction and repulsion, but the electrostatic force is stronger.

C) both have thesame dependence on distance, the electro-static force can be either attractiveor repulsive while the gravitational force is only attractive, and theelectrostatic force is stronger.

D) both have thesame dependence on distance, the electrostatic force can be either attractiveor repulsive while the gravitational force is only repulsive, and theelectrostatic force is weaker.

E) the electrostatic force falls off more rapidly with distance, the electrostatic force can be either attractive or repulsive while gravitation is only attractive, and the electrostatic force is stronger.

20) A 10 µC charge is at the origin. A -15 µC charge is on the x-axis 10 cm to the right of the origin. At what point other than at infinity can a 1 µC charge be placed so that there will be no net electrostatic force on it?

A) at one point on the x-axis to the left of the positive charge B) at some point off the x-axis either above or below C) at one point between the two charges D) at one point on the x-axis to the right of the negative charge E) at no point

21) Two equal charges repel one another with a force of 4.0 × 10-4 N when they are 10 cm apart. (Coulomb's constant is k=9.0 × 109 N.m2/C2.) If they are moved until the separation is 5 cm, the repulsive force will be A) 0.25 ×10-4 N. B) 1.0 × 10-4 N. C) 4.0 ×10-4 N. D) 16 ×10-4 N. E) 64 ×10-4 N.

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22) A positive charge is fixed at the origin. A negative charge is moved along the x-axis from x = 50 cm to x = 10 cm. The potential energy of the system

A) does not change.

B) decreases.

C) increases.

23) Imagine four equal positive charges, q, placed on points of a circle of radius r at the 3, 6, 9, and 12 o'clock positions. Coulomb's constant is k. The magnitude of the electric field at the center of the circle is given by

A) 4 kq/r.

B) 4 kq/r2.

C) kq/r.

D) kq/r2.

E) zero.

24) Three equal negative charges are placed at three of the four corners of a square. The direction of the electric field at the remaining corner of the square is

A) along a side ofthe square toward one of the charges.

B) along a side of the square away from one of the charges.

C) along the lineconnecting this corner with the opposite corner, and toward that corner.

D) along the lineconnecting this corner with the opposite corner, but away from thatcorner.

E) no direction, zero field.

25) A uniform electric field has a magnitude of 10 N/C and is directed upward. A charge brought into the field experiences a force of 2.0 N upward. The charge must be

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A) +20 C. B) -20 C. C) +0.2 C. D) -0.2 C. E) -2.0 C.

26) A capacitor consisting of two parallel plates separated by 2.0 cm has a potential of 40 V on the top plate and a potential of 0 V on the bottom plate. The electric field in the middle is

A) 2000 N/C,downward.

B) 80 N/C,upward.

C) 40 N/C,downward.

D) 20 N/C,upward.

27) A capacitor consisting of two separated parallel horizontal plates has a uniform electric field directed upward. If a negative charge is placed exactly midway between the two plates, it will

A) be acceleratedupward.

B) be accelerateddownward.

C) remain atrest.

D) be accelerated to the right.

E) be accelerated to the left.

28)

The unit for electric field, N/C, can be written equivalently as

A) V/m.

B) C/V. C) V/C. D) m/V. E) V.

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29)

Two charges are shown. What is the direction of the electric field at the indicated point?

A) A B) B C) C D) D E) E

30) When you shuffle your feet on a carpet on a dry day, you can accumulate a charge. The fact that you accumulate a charge means that the carpet is

A) an insulator,because if it weren't, the charge would immediately leave you.

B) an insulator,because only insulators can be charged by contact.

C) a conductor,because charge cannot leave an insulator and move to you.

D) a conductor,because conductors always have extra electrons.

31) Two charges of equal magnitude but opposite sign are 10 cm apart. The potential is largest

A) halfway betweenthe two charges.

B) close to thepositive charge.

C) close to the negative charge.

D) far away from thetwo charges.

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32)

A charged comb attracts bits of neutral dust in the air. This happens because

A) the dust becomespolarized.

B) the dust groundsthe comb.

C) the dust becomescharged by induction.

D) the dust is a good conductor.

33) A point charge creates the electric field shown. At which of the points would the potential energy of a positive test charge have the largest value?

A) A B) B C) C D) D

34) If two metal balls each have a charge of -10-6 C and the repulsive force between them is 1 N, how far apart are they? (Coulomb's constant is k=9.0 × 109 N.m2/C2.)

A) 9.5 m B) 9.0 mm C) 9.5 cm D) 0.9 m

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35) The most common form of lightning strike from a cloud to the ground involves negative charge moving from the cloud to the ground. Just before a lightning strike,

A) the electricfield must point toward the sky.

B) the potentialenergy of the electrons in the cloud must be small.

C) the potential must be larger near the cloud.

D) there are no charges on the ground.

36) Consider the field lines of the electric dipole in this diagram, relative to the w-axis and the z-axis.

In which direction does the electric field point where the two axes intersect?

A) 45° up and to the right, parallel to the z-axis: B) 45° down and to the right, parallel to the w-axis: C) 45° down and to the left, parallel to the z-axis: D) 45° up and to the left, parallel to the w-axis:

37) You have a pair of horizontal parallel plates, with the positive plate above and the negative plate below. How will the lines of constant potential be arranged in this perspective?

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A) spherically, since all charges are either electrons or protons B) horizontally C) vertically

38) Consider horizontal parallel plates with a fixed potential difference. The upper plate has a voltage difference of 30 V with the lower plate, and they are separated by 3 cm. You move the two plates carefully to a separation of 4 cm. What is the strength of the electric field between the plates?

A) 3000volts/meter B) 1000volts/meter C) 750volts/meter D) 7.5volts/meter

39) As a given thundercloud's base elevation gets lower and lower, the possibility of lightning strike

A) is greater,because the electric field strength increases.

B) is less, sincethe electric field gets weaker.

C) is unchanged, because the thundercloud has not polarized.

40) If the plates of a charged parallel plate capacitor were moved further apart, while the charge on the plates is kept constant, the potential energy of each of the charges on the capacitor would

A) remain thesame.

B) increase.

C) decrease.

D) increase ordecrease depending on the initial plate separation.

41) If a charge of -3 x 10-6 C were allowed to fall through a potential difference of +500 V, the change in potential energy for the charge would be Version 1

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A) -1.5 × 10-4 Joules.

B) 1.5 × 10-4 Joules.

C) -1.5 × 10-3 Joules.

D) 1.5 × 10-3 Joules.

42) Electrostatic precipitators can effectively remove most of which of the following air pollutants from a smoke stack?

A) sulfur dioxide B) carbon monoxide C) nitrous oxides D) particulates

43) Two very small spherical metal objects, each with 2 Coulombs of charge, are brought together in a vacuum so that the separation distance between their centers is 1 mm. What is the force of repulsion between the two objects? (Coulomb's constant is k=9.0 × 109 N.m2/C2.)

A) 36 × 1012 N B) 36 × 1013 N C) 36 × 1014 N D) 36 × 1015 N

44) To bring a negative charge from an infinitely great distance away into the presence of a positive charge would require a amount of work to be done.

A) positive B) negative C) zero

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FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

45) A plastic rod is rubbed with fur. The rod is then touched to the metal knob of an electroscope. The sign of the charge on the electroscope after contact is .

46) A glass rod is rubbed with nylon. The rod is then brought close to the metal knob of an electroscope. A person's finger briefly touches the knob on the far side and is then removed.

After the rod is removed the charge on the electroscope will be .

47)

A positive test charge is moved closer to a negative charge. The potential of the system (indicate whether it increases, decreases, or stays the same).

48) It is observed that a negatively charged grain of soot released between the parallel plates of a capacitor moves leftward. The direction of the electric field between the capacitor plates is .

49) A negatively charged grain of soot released between the parallel plates of a capacitor moves leftward. The potential between the parallel plates (indicate whether it increases, decreases, or stays the same) from right to left, and the potential energy of the negatively charged grain of soot (indicate whether it increases, decreases, or stays the same) from right to left.

50) In a certain region of space, lines of constant positive electric potential around a positive charge get farther apart as one moves to the right. The force on a negative charge in this region will point to the .

51) A drop of water dripping from the faucet in your kitchen is electrically neutral. A charged plastic hair comb can attract the drips and drops by the process of .

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52) Negative charges feel a force potentials.

(indicate direction) values of higher electric

53) Four equal positive charges are placed at the corners of a square. The force on a +1 C charge placed at the center due to any single charge is 10 N. The value of the electric field at the center due to the charges at the corners is N/C.

54) If a negatively charged rod is brought close to (but not touching) an initially neutral object, the object becomes polarized and has charge.

55) A device used by Charles Coulomb to measure the presence or absence of electric charge is called a(n)

56)

Electrical force per unit charge is known as the

57) The change in electrical potential energy per unit of charge that is moved from one place to another is known as .

SECTION BREAK. Answer all the part questions.

58) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

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58.1) Refer to the dipole in the z, w coordinate system. Consider the electric field at a point α out on the z-axis, above and to the right of the intersection of the axes. In which direction does the electric field point at point α?

A) 45° down and tothe right, parallel to the w-axis: B) 45° up and to theright, parallel to the z-axis: C) 45° up and to theleft, parallel to the w-axis: D) 45° down and tothe left, parallel to the z-axis:

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Answer Key Test name: Chap 12_10e 1) D 2) B 3) A 4) D 5) C 6) A 7) C 8) D 9) C 10) A 11) B 12) E 13) A 14) C 15) B 16) D 17) A 18) C 19) C 20) A 21) D 22) B 23) E 24) C 25) C 26) A Version 1

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27) B 28) A 29) D 30) A 31) B 32) A 33) D 34) B 35) A 36) D 37) B 38) C 39) A 40) B 41) C 42) D 43) D 44) B 45) negative 46) negative 47) decreases 48) rightward 49) [increases, decreases] 50) left 51) polarization 52) toward 53) zero 54) no 55) electroscope 56) electric field Version 1

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57) voltage difference 58) Section Break 58.1) C

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CHAPTER 13 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) A household circuit rated at 120 volts is protected by a fuse rated at 10 amps. What is the maximum number of 100 watt light bulbs which can be lit simultaneously in parallel in this circuit without blowing the fuse?

A) 4 B) 8 C) 12 D) 20 E) 24

2)

The current (measured in amperes) in a circuit is

A) the total numberof electrons in the circuit.

B) the amount of the total energy carried by 1 Coulomb of charge.

C) the amount ofcharge (measured in Coulombs) that passes a point (in the circuit) in 1second.

D) never lethal if the current is due to positive charges.

3)

The resistance of a circuit element is a measure of

A) the amount of workthat an electron can perform.

B) the ratio of thevoltage difference between element ends to the current in the element.

C) the size of thecircuit.

D) the total energyof the charges in the circuit element.

4) A certain kind of lightbulb carries 0.5 amperes of current when connected to a 120 volt AC circuit. What is its power rating?

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A) 240 W B) 100 W C) 75 W D) 60 W

5) The resistance of a 50 watt bulb is voltage.

that of a 100 watt bulb, if both run on the same

A) one half B) one fourth C) four times D) double

6) Two identical lightbulbs are installed in two sockets connected in parallel and power is then applied to the combination so that both bulbs light. If one of the bulbs is then removed from its socket, the other one will

A) get brighter.

B) get dimmer.

C) remain equallybright.

D) go out.

7) Bulbs A, B, C, and D are identical and connected to a battery as shown. The bulb with the least current passing through it is

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A) bulb A. B) bulb C. C) both bulbs A andB. D) both bulbs C and D.

8) A flashlight bulb typically has a small metallic button at one end, and this button is surrounded by ceramic material. The chief purpose of the ceramic material is to

A) provide aconducting path to the filament.

B) shut the filamentoff if the current gets too high.

C) provide extra mass at the bottom of the bulb.

D) insulate the metalbutton from the other contact point.

9) In many ways, an electric circuit is like the plumbing system in your home. The voltage on an electric circuit corresponds to the in a plumbing system.

A) trap B) pressure C) faucet orvalve D) drain

10)

An ohm is equal to which of these?

A) a volt B) a Coulomb per second C) an ampere per second D) a volt per ampere

11) A 1.5 V flashlight battery, a 10 ohm resistor, and a flash-light lamp are available. How should the lamp be connected in a circuit so that it would glow the brightest?

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A) Connect it in series with the resistor and battery so that the bulb is next to the positive terminal of the battery.

B) Connect it directly to the battery; don't use the resistor.

C) Connect it in parallel with the battery and the resistor.

D) Connect it in series with the resistor and battery so that the bulb is next to the negative terminal of the battery.

12)

One ampere is equivalent to

A) 1 J/s.

B) 1 C/s.

C) 1 N/C. D) 1 V/m.

E) 1 ohm/volt.

13) A 9 ohm resistor and a 16 ohm resistor are connected in series in a circuit with a 5.0 volt battery. Assuming negligible internal resistance in the battery, the current in the 16 ohm resistor will be

A) 0.20 A. B) 0.5 A. C) 1.0 A. D) 12 A. E) 0.16 A.

14) A 12 ohm resistor and a 24 ohm resistor are connected in parallel across a 6.0 V battery.

The correct statement from the following is

A) the current is the same in each resistor.

B) the power dissipated is the same in each resistor.

C) the voltage difference between the ends of each resistor is the same.

D) the larger current is in the larger resistor.

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15) A 12 ohm resistor and a 24 ohm resistor are connected in series with a 6.0 V battery. The correct statement is

A) the voltage difference between the ends of each resistor is the same.

B) the powerdissipated in each resistor is the same.

C) the current ineach resistor is the same.

D) the smaller resistor carries the larger current.

16) The voltage drop across a resistor is 4.0 V for a current of 1.0 A in the resistor. What is the current that will produce a voltage drop of 8.0 V across the resistor?

A) 0.33 A B) 1 A C) 2 A D) 0.50 A

17)

The unit for electromotive force (emf) is

A) N. B) A. C) ohm.

D) N/C. E) V.

18) Three bulbs have power ratings for use on a 120 volt line: 60 watt, 100 watt and 150 watt.

The one with the largest value of resistance has power rating

A) 150 W. B) 100 W. C) 60 W. D) All of these choices have the same resistance.

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19) A heater is rated to dissipate 2880 W when connected to a 120 V source. The current drawn by the device is

A) 0.133 A. B) 24 A. C) 60 A. D) 30 A. E) 240 A.

20) An unmarked resistor is being used in a circuit. To determine its resistance by making voltage and current measurements, one should connect

A) the voltmeter and ammeter in parallel with the resistor.

B) the voltmeter and ammeter in series with the resistor.

C) the voltmeter inseries with the resistor, and the ammeter in parallel with the resistor.

D) the voltmeter inparallel with the resistor, and the ammeter in series with the resistor.

21) A student finds two ancient meters with numbered scales but no unit markings. He thinks that one is an ammeter and one is a voltmeter but doesn't know which is which. He measures the resistance of each, finding that meter A has a resistance of 5000 ohms and meter B has a resistance of 0.10 ohm. He can conclude that

A) B is thevoltmeter and A is the ammeter.

B) A is thevoltmeter and B is the ammeter.

C) A is thevoltmeter but B cannot be a useful meter.

D) B is thevoltmeter but A cannot be a useful meter.

E) neither can be a useful meter.

22) The potential difference across the terminals of a storage battery not connected in any circuit is observed to be 12 V. When it is connected to an external resistance the potential difference across the terminals is observed to be 11 V while the current in the external resistance is 3 A. What is the internal resistance of the battery?

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A) 5.5 ohms B) 2.0 ohms C) 1.0 ohm D) 0.33 ohm E) Zero ohms

23) A person discovers that the 5 ampere fuse in his car's brake light circuit is blown. Not having a spare 5 ampere fuse available, he replaces it with a new 10 ampere fuse. What is likely to happen as he uses the brakes?

A) Nothing bad happens; everything works well for a long time.

B) The brake lights shine more dimly than before.

C) The circuit overheats and the brake lights do not work.

D) The fuse blows immediately.

24) The alternating current in wide use in homes in North America is 60 cycles per second, or 60 Hz. How many times per minute does this current reverse its direction of travel?

A) 60 times B) 120 times C) 3600 times D) 7200 times E) None of these choices are correct.

25)

Which of these is an electronic instrument that can plot voltage as it varies with time?

A) an ammeter B) a galvanometer C) an electroscope D) an oscilloscope

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26)

When you pay your electric bill, what are you paying for, exactly?

A) the electrical energy you used the previous month B) the voltage you used the previous month C) the electrical charge you used the previous month D) the electrical power you used the previous month E) None of these choices are correct.

27) You have exactly 4 resistors: one 3 Ω, one 4 Ω, one 5 Ω, and one 6 Ω. How can you combine these to make a 2 Ω resistor? (The symbol Ω stands for "ohm.")

A) Connect the 3 Ω resistor in series with the 5 Ω resistor B) Connect the 3 Ω resistor in parallel with the 6 Ω resistor C) Connect the 3 Ω resistor in parallel with the 4 Ω resistor D) Connect all four resistors in parallel with each other E) You can't make a 2 Ω resistor from the choices listed

28) Three identical resistors can be connected in any combination. It's not necessary to include all three in any given combination. The number of distinct values of resistance that can be made is

A) two or fewer.

B) three.

C) four.

D) five.

E) six or more.

29) A power rating printed on a lightbulb assumes a voltage of 120 V is applied to the bulb.

If two 100 W bulbs are connected in series to a 120 V source,

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A) no current willpass through the bulbs.

B) each bulb radiates 100 W. C) each bulb radiates more than 100 W. D) each bulbradiates less than 100 W.

30) then

If the resistance in a circuit using an ideal (no internal resistance) battery is increased,

A) the current coming out of the battery does not change.

B) the voltage difference maintained by the battery does not change.

C) the power output of the battery does not change.

D) All of these choices are correct.

31) Toasters have wires in them that heat up to warm the items placed inside. For the toaster to work properly, these wires must

A) be connected to a very large voltage.

B) have lessresistance than the power cord.

C) be connected to atiny voltage.

D) have moreresistance than the power cord.

32) Resistors of 10 ohms, 20 ohms, and 30 ohms are connected in series with a battery. The 10 ohm resistor is closest to the positive terminal and the 30 ohm resistor is closest to the negative terminal. What happens as the current flows through this circuit?

A) The most current is consumed in the 10 ohm resistor, less in the 20 ohm resistor, and the least in the 30 ohm.

B) A little current is consumed in the 10 ohm resistor, more in the 20 ohm, and the most in the 30 ohm.

C) The resistors each consume the same amount of current.

D) None of the resistors consume current.

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33) The current through a circuit consisting of a single battery and single resistor is measured to be 0.25 ampere. Another identical battery and another identical resistor are added to the circuit. The current passing through the circuit is

A) 0.125 A. B) 0.25 A. C) 0.50 A. D) dependent on howthe battery and resistor are added to the circuit.

34) Three different resistance lightbulbs are connected to a 120-V outlet. The most power will be consumed by the circuit

A) when the bulbs are in series.

B) when the bulbs are in parallel.

C) when the least resistive bulb is in parallel with a series of the other two.

D) when the most resistive bulb is in parallel with a series of the other two.

E) The arrangement is unimportant because the voltage is the same in all cases.

35) An electric iron uses 8.0 A of current and has a power rating of 1100 W. The resistance of the iron is A) 0.0072 Ohms.

B) 17 Ohms.

C) 138 Ohms.

D) 8800 Ohms.

36) A copper wire from a large spool is cut into two lengths to make extension cords, one 50 feet long and the other 75 feet long. Which of the following is true?

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A) The shorter cord will dissipate more power.

B) The shorter cord will have a smaller voltage.

C) The longer cord will be able to carry more current.

D) The longer cord will have more resistance.

37) An iPod battery is rated at 3.7 volts and operates its iPod and earbuds with a direct current of 865 milliamps. What is the power rating of this iPod?

A) 16 Watts B) 234 Watts C) 3.2 Watts D) 3.7 Joules persecond

38) An iPod uses 3.7 volts with direct current of 865 milliamps. What is the equivalent resistance of the entire iPod system?

A) 4.3 ohms B) 1 ohm C) 3200 ohms D) 8.4 ohms

39) In a laptop computer, the power converter plugs into the wall's AC outlet and it plugs into the computer's DC power jack. The direct current is composed of

A) electrons moving in the wire.

B) protons moving through the wire.

C) both protons and electrons moving through the wire in the same direction.

D) exactly one half of the voltage of the AC that operates the power converter.

40) When a nerve cell fires in your big toe, it is an interaction of positive and negative ions in the membrane of the nerve cell. This membrane has structural similarities to

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A) a point charge.

B) oppositelycharged parallel plates.

C) a dipole.

D) a solid block of positive ions embedded with a few impurities in the form of negative ions.

41)

If you load up a circuit in your home with too many devices, like lightbulbs or stereos, in , then you can overload the circuit and trip a circuit breaker or blow a fuse.

A) series B) parallel C) summer D) duplicate

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

42) A resistor R is connected across a battery of negligible internal resistance. If the resistance of R is doubled, the current in R will be .

43) In the water flow analogy with an electric circuit the pressure in the fluid circuit is analogous to in the electric circuit.

44) In the water flow analogy with an electric circuit the flow meter in the fluid circuit is analogous to the in the electric circuit.

45) A one ohm, a two ohm, and a three ohm resistor are connected in parallel in an electric circuit: The resistor dissipating the most power will be the ohm resistor.

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46) A dry cell battery is no longer useful when its becomes large.

(two words)

47) A student finds three resistors in the lab: a two ohm, a five ohm, and a 10 ohm resistor.

The smallest value of resistance that the student can make using any one or any combination of the three resistors is ohms.

48)

In a series circuit, the most power is dissipated where the resistance is

49)

As the temperature of a wire increases, its

.

also increases.

50) A resistor R is connected across a battery of negligible internal resistance. If the resistance of R is cut in half, the power dissipated in R will (indicate change, if any).

SECTION BREAK. Answer all the part questions.

51) NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

Power supply :

Series connection:

Parallel connection:

51.1) What is the best way to ensure that a 40 watt bulb and a 60 watt bulb have the same voltage applied to them?

A) Connect the bulbs in series with the power supply.

B) Connect the bulbs in parallel with the power supply.

C) It can't be done; different wattage bulbs must always have different voltages.

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51.2) What is the best way to ensure that a 40 watt bulb and a 60 watt bulb have the same current within them?

A) Connect the bulbs in series with the power supply.

B) Connect the bulbs in parallel with the power supply.

C) It can't be done; different wattage bulbs must always have different currents.

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Answer Key Test name: Chap 13_10e 1) B 2) C 3) B 4) D 5) D 6) C 7) C 8) D 9) B 10) D 11) B 12) B 13) A 14) C 15) C 16) C 17) E 18) C 19) B 20) D 21) B 22) D 23) C 24) D 25) D 26) A Version 1

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27) B 28) D 29) D 30) B 31) D 32) D 33) D 34) B 35) B 36) D 37) C 38) A 39) A 40) B 41) B 42) halved 43) voltage 44) ammeter 45) one 46) internal resistance 47) 1.25 48) largest 49) resistance 50) increase 51) Section Break 51.1) B 51.2) A

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CHAPTER 14 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) Electrons flow around a circular wire loop in a horizontal plane, in a direction that is clockwise when viewed from above. This causes a magnetic field. Inside the loop, the direction of this field is

A) toward the centerof the loop.

B) radially outwardfrom the center of the loop.

C) up, toward theviewer.

D) down, away from theviewer.

2) A horizontally moving positive sodium ion enters a magnetic field that points up. The magnetic force pushes the charge out of its original path.

When viewed as shown on this page, what direction will the magnetic force point?

A) into the page B) out of the page C) There is not enough information to answer.

3)

Which of these will always produce a magnetic field?

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A) a positive charge at rest B) another magnetic field C) a moving charge D) a negative charge at rest

4) Imagine that this classroom contains a constant magnetic field that points from the front to the back. In front of you a negative charge is slowly moving horizontally to your left. As you watch, the magnetic force on the charge

A) deflects thecharge away from you.

B) deflects thecharge into a clockwise directed vertical circle.

C) deflects thecharge toward you.

D) has no effect onthe charge.

E) deflects thecharge into a counterclockwise vertical circle.

When a current is induced by a changing magnetic field B1, the current always produces a 5) second magnetic field B2 such that

A) B1 and B2 completelycancel each other out.

B) B1 and B2 combine togive a stronger magnetic field than B1alone.

C) B1 and B2 combine togive a weaker magnetic field than B1 alone.

D) It is not possible to tell whether the combined field is stronger or weaker than B1 without knowing how B1 is changing.

6)

A permanent magnet is produced when

A) magnetic fields oflarge groups of individual atoms are permanently aligned.

B) electrons becomestuck and cease to move.

C) electrical fieldsexchange electrons with the magnetic fields.

D) current is made tocirculate in a clockwise direction in a loop of wire.

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7) A positive charge is released from rest near a bar magnet. The magnetic force on the charge

A) there is no magnetic force on the charge.

B) either pole of the magnet will repel the positive charge.

C) can only be attracted toward the S pole of the magnet.

D) can only be attracted toward the N pole of the magnet.

8) A bar magnet and an electrically polarized object are placed next to each other on a table.

What happens?

A) The positive part of the object turns toward the north pole of the magnet.

B) The positive part of the object turns toward the south pole of the magnet.

C) The object and magnet accelerate toward each other until they touch and then they repel.

D) Nothing happens.

9)

A current flowing through a long, straight wire causes a magnetic field that points

A) along thewire.

B) along concentriccircles around the wire.

C) radially inwardtoward the wire.

D) radially outwardfrom the wire.

10) A little magnetic compass has a needle whose tips are clearly labeled N and S. The compass is placed next to a single circular loop of wire lying flat on a wooden table. The current in the loop is clockwise. What happens?

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A) The S tip of the needle is attracted toward the loop.

B) The N tip of the needle is attracted toward the loop.

C) The needle orients itself with the N tip pointing in the direction of the current in the segment of the loop closest to the needle.

D) The needle orients itself with the S tip pointing in the direction of the current in the segment of the loop closest to the needle.

E) None of these choices are correct.

11)

A magnetic compass points towards the north geographic pole of the Earth because

A) all magneticpoles, north or south, point that way due to the spin of the Earth.

B) the staticelectricity in the atmosphere causes the alignment of the compass.

C) there is a northmagnetic pole near the north geographic pole.

D) there is a southmagnetic pole near the north geographic pole.

12) Two identical coils of wire are placed on a single horizontal wooden broom handle. The coils are separated by a few centimeters. We now run identical currents in the same direction through each coil. The coils experience

A) no forces because the currents are identical.

B) a repulsivemagnetic force.

C) an attractivemagnetic force.

D) an attractive electrostatic force because one coil is negatively charged and the other positively charged.

E) a repulsive electrostatic force because both coils are identically charged.

13)

Which of the following cannot induce a voltage in a loop of wire?

A) moving a magnet near the loop B) moving the loop near a magnet C) expanding or contracting the loop in a region where there is no magnetic field D) changing the current in a nearby loop

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14) An ideal transformer is used to either increase or decrease the voltage in an AC circuit.

When the output voltage is greater than the input voltage of a transformer then

A) the power outputdepends on the ratio of turns in the primary and secondary.

B) the power output is the same as the power input.

C) the power output is larger than the power input.

D) the power outputis smaller than the power input.

15) A positively charged ping pong ball is sitting stationary on the floor in the center of a room. There is also a constant, uniform magnetic field in the room that points toward the ceiling.

If I now start the ball rolling toward the back of the room, the resultant motion of the ball, as observed from the ceiling, will be

A) a diagonal straight line toward the left back corner of the room.

B) a diagonalstraight line toward the right back corner of the room.

C) a horizontal,clockwise circle.

D) a horizontal, counterclockwise circle.

E) a straight linein the original direction of motion.

16) A battery is causing a large current in a solenoid (helical coil of wire). A bar magnet is held at rest nearby, aligned with the axis of the solenoid, with its south pole closest to the solenoid. The bar magnet is being repelled by the solenoid. Which of the following statements is true of the conventional current in the solenoid?

A) The current in the solenoid increases.

B) The current in the solenoid decreases.

C) The current in the solenoid is flowing counterclockwise as seen from the bar magnet.

D) The current in the solenoid is flowing clockwise as seen from the bar magnet.

E) The direction of the current in the solenoid alternates with a constant frequency.

17) Bar A has one end painted green and the other end red and may or may not be a magnet.

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A) A is not amagnet.

B) A is a magnet andthe green end is a north pole.

C) A is a magnet andthe green end is a south pole.

D) A might be a magnet; this observation does not provide enough information to determine whether or not it is.

18) The south pole of a bar magnet is moved toward an aluminum ring, along the axis of the ring. As the magnet approaches, the changing magnetic flux induces an electric current in the ring that, when seen from the bar magnet, corresponds to positive charge carriers flowing

A) clockwise.

B) counterclockwise.

C) alternating with a fixed frequency.

D) alternating witha frequency proportional to a speed of the bar magnet.

19) A horizontal straight wire carries a current from east to west. The resulting magnetic field lines are

A) straight linesperpendicular to the wire.

B) parallel to thewire from west to east.

C) parallel to thewire from east to west.

D) closed circlesperpendicular to the wire directed counterclockwise as viewed from theeast.

E) closed circlesperpendicular to the wire directed clockwise as viewed from the east.

20)

Magnetic fields affect

A) neither electriccharges in motion nor electric charges at rest.

B) both electriccharges in motion and electric charges at rest.

C) only electriccharges in motion.

D) only electriccharges at rest.

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21)

The scientist credited with discovering that electric currents produce magnetic fields was

A) Oersted.

B) Ampere.

C) Coulomb.

D) Tesla.

E) Faraday.

22)

The magnetic pole near the Earth's north geographic pole actually has to be

A) an N pole becauseit repels the S pole of your compass needle.

B) an S pole,because it attracts the N pole of your compass needle.

C) either an N or an S pole, but scientists have not determined which one yet.

23) Two long bar magnets are aligned so that north poles face each other. The magnets are separated by 1 cm, and a repulsive force between the north poles is 0.04 N. When the separation is increased to 2 cm the force will be

A) 0.010 N. B) 0.020 N. C) 0.025 N. D) 0.40 N. E) 0.050 N.

24) Two current-carrying wires are parallel to one another and separated by 1 cm. If the distance between them is increased to 2 cm the new force will be what factor times the original force?

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A) ¼ B) ½ C) 1 D) 2 E) 4

25) A long straight wire carries a current. A positive charge moves toward the wire in a direction perpendicular to the wire. The direction of the force on the charge will be

A) parallel to thewire in the direction of the current.

B) parallel to thewire opposite the direction of the current.

C) in the directionof the charge's velocity.

D) opposite thedirection of the charge's velocity.

E) There is no force.

26) Imagine a magnetic field pointing into the plane of this page. An electron moves across the paper from left to right. The direction of the magnetic force on the electron will be

A) into the plane of the paper.

B) out of the plane of the paper.

C) in the plane of the paper and toward the top of the page.

D) in the plane ofthe paper and toward the bottom of the page.

E) in the plane ofthe paper and opposite the electron's velocity.

27) The correct expression for magnetic flux through area A, where B is a constant magnetic field and A is an area perpendicular to the field, is

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A) B/A. B) B × A. C) B + A. D) A/B. E) 1/(B ×A).

28) Think of a closed rectangular loop of wire around the edge of a horizontal page. A magnetic field perpendicular to the page points upward and increases in strength in a certain time. During this time the conventional current induced in the loop will be A) clockwise.

B) counterclockwise.

C) zero.

D) continually changing direction.

29) A transformer has 200 turns on the primary and 20 turns on the secondary. The primary is connected to a direct current source of 100 millivolts. The voltage in the secondary coil will be A) zero.

B) 10millivolts.

C) 20millivolts.

D) 1000millivolts.

E) 4000millivolts.

30) A transformer is to be used to step down voltage from an alternating current source from 220 V to 110 V. If the primary has 120 turns, then the number of turns in the secondary is

A) 2.

B) 60.

C) 280.

D) 840.

E) 1540.

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31) The south pole of a bar magnet is moved toward a short helical coil of wire (solenoid) along the axis of the coil. The coil has 100 turns and the ends of the coil are connected to form a closed circuit. If the coil is replaced with a single loop of the same type of wire, and the magnet is moved exactly as before, the current induced in the loop is

A) the same as inthe coil.

B) zero in bothcases.

C) 100 timessmaller.

D) 100 timeslarger.

32) The south pole of a bar magnet is moved toward a short helical coil of wire (solenoid) along the axis of the coil. The coil has 100 turns and the ends of the coil are connected to form a closed circuit. If the coil is replaced with a single loop of the same type of wire, and the magnet is moved exactly as before, the magnet experiences a force that is

A) the same as before.

B) attractive and100 times larger.

C) attractive and 100 times smaller.

D) repulsive and 100 times larger.

E) repulsive and 100times smaller.

33)

In the southern hemisphere, the north pole of a compass needle

A) points toward the south geographic pole because there is a south magnetic pole there.

B) points toward the south geographic pole because that is the nearest magnetic pole.

C) points away from the south geographic pole because there is a north magnetic pole there.

D) spins aimlessly because the north geographic pole is beyond the horizon.

34)

If an electron is placed at rest near a bar magnet, the electron will

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A) accelerate awayfrom the negative pole of the magnet.

B) not move atall.

C) be attracted tothe positive pole of the magnet.

D) move in acircular path around the north pole of the magnet.

35) A bar magnet is broken in half and the magnetic field around one piece is mapped out.

What is wrong with this picture?

A) The field lines are pointing in the wrong direction.

B) The field lines should converge on the "N".

C) There is no south pole.

D) Nothing; this is how the field looks around a broken magnet.

36) This sketch shows a bar magnet in a loop of wire with the bar perpendicular to the plane of the loop. The left-hand side shows the magnet being spun around its long axis while on the right side the magnet is turned end-over-end. Which case creates a larger induced current in the loop?

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A) the right-hand side B) the left-hand side C) Neither situation produces an induced current.

D) The induced current is the same in each case and is not zero.

37) A loop of wire is oriented in the magnetic field as shown (the plane of the loop is perpendicular to the direction of the magnetic field and the magnetic field strength increases with height). Which of the following is true?

A) There will be an induced current only if the loop is moved to the left.

B) There will be an induced current only if the loop is moved to the right.

C) There will be an induced current only if the loop is moved upward.

D) There will be an induced current only if the loop is moved downward.

E) There will be an induced current if the loop is moved either up or down.

38) Two particles move into a magnetic field. They enter moving at the same speed and direction. The magnitude of the charge on each is known to be the same. One particle curls to the right and the other to the left upon entering the field, the leftward moving particle moves in a larger circle than the rightward moving particle. From this we can say that A) the leftward moving particle has more mass and is positively charged.

B) the rightward moving particle has less mass and is positively charged.

C) the leftwardmoving particle has more mass and its charge is opposite the otherparticle.

D) the rightwardmoving particle has positive charge but we cannot say anything about itsmass.

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39)

If an electron moves in a magnetic field,

A) it always feels a force.

B) it only feels aforce if its velocity vector is parallel (or antiparallel) to the direction ofthe magnetic field.

C) it only feels a force if its velocity vector is not parallel (or antiparallel) to the direction of the magnetic field.

D) it does not feel a force if it is in motion, only if stationary.

40) In outer space, you observe a straight stream of electrons flowing past you at 14.5 miles per second, about the same speed that Mars moves on its orbit around the sun.

You maneuver your spacecraft to face the current so that the electrons are moving from left to right and so that you are 10 m from the stream. In what direction does a compass needle point?

A) up B) down C) left D) right E) You observe no magnetic field.

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41) In outer space, you observe a straight stream of electrons flowing past you at 14.5 miles per second, about the same speed that Mars moves on its orbit around the sun.

You maneuver your spacecraft to face the current so that the electrons are moving from left to right and so that you are 10 m from the stream. Now you fire your rockets and boost your speed so that you are also moving at 14.5 miles per second, exactly at the same speed and direction as the electrons. In what direction does a compass needle point now?

A) up B) down C) left D) right E) You observe no magnetic field.

42) You see a positively charged helium ion in space, and it is at rest with respect to your spacecraft. Since you are studying for the final exam, you decide to experiment. You slowly push the N pole of a bar magnet closer to the helium ion. What happens to the helium ion?

A) It experiences a magnetic force and moves off.

B) It depends on whether it is a positive ion or a negative ion.

C) Nothing happens, because the ion is not moving.

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43) You could use two parallel wires to move objects 1 and 2 apart if each wire is embedded in its own object and if

A) the currents inthe wires are in opposite directions.

B) the currents inthe wires are in the same direction.

C) one wire carries a current and the other wire has zero current.

44) What would happen if you had a car made completely of plastic, with no metal parts, and you drove over a vehicle sensor embedded in the road surface?

A) You would overload the sensor, so this is an excellent method for forcing all lights to turn green.

B) The circuit would detect the absence of magnetic flux, thereby working normally.

C) The sensor would signal with the opposite polarity, indicating you've already gone through the intersection.

D) The sensor would not notice you or your vehicle, and you'd be stuck at the red light.

45) When a switch is closed allowing current to flow in coil A, the current induced in a nearby coaxial but unconnected coil B will flow

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A) only momentarily and then stop.

B) steadily until the current flow in A is shutoff.

C) will not flow at all since the coils are not connected.

D) will keep flowing long after the current in A is shut off.

46) If a current of negative charge flows in a circle in the direction of one's curled fingers of the right hand, the resulting magnetic field would be in the direction

A) of the rightindex finger.

B) of the thumb ofthe right hand.

C) opposite to thethumb of the right hand.

D) of due north.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

47) The S.I. unit used in expressing magnetic field strength is the .

48)

Two parallel wires each carrying a current in opposite directions will one another.

49) When there is a changing magnetic flux through an electric circuit, the direction of the induced current in the circuit is determined by Law.

50) The north pole of a bar magnet is moved away from a single closed loop of wire along the axis of the loop. The induced current in the loop produces an effective pole toward the bar magnet.

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51) A bar magnet is held near a single closed loop of wire. The magnet is aligned with the loop axis, and the north pole is facing the loop. If the magnet is moved away, the current induced in the loop will be in a direction as viewed from the side the magnet is on.

52) A step-up transformer that doubles the input voltage is designed to work with an input voltage that varies at 60 Hz. The frequency with which the output voltage varies is Hz.

53)

Faraday's Law states that a voltage is induced in a circuit when there is a changing passing through the circuit.

54) A solenoid carrying an electric current, if free to rotate when placed in a magnetic field, will tend to orient its axis (parallel, perpendicular, antiparallel) to the magnetic field.

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Answer Key Test name: Chap 14_10e 1) C 2) B 3) C 4) E 5) D 6) A 7) A 8) D 9) B 10) E 11) D 12) C 13) C 14) B 15) C 16) D 17) D 18) A 19) E 20) C 21) A 22) B 23) A 24) B 25) B 26) D Version 1

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27) B 28) A 29) B 30) B 31) C 32) E 33) C 34) B 35) C 36) A 37) E 38) C 39) C 40) A 41) E 42) C 43) A 44) D 45) A 46) C 47) Tesla 48) repel 49) Lenz's 50) south 51) clockwise 52) 60 53) magnetic flux 54) parallel

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CHAPTER 15 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) Electromagnetic waves are generally

A) longitudinalwaves.

B) transversewaves.

C) a 50/50combination of transverse and longitudinal waves.

D) standingwaves.

2)

The period and the frequency of a sound wave are

A) independent ofeach other.

B) multiples of eachother—period is 2π times the frequency.

C) reciprocals ofeach other.

D) None of these choices are correct.

3)

The Doppler effect refers to changes in a sound wave's

A) frequency causedby motion of a source or receiver.

B) frequency causedby a change in speed of sound.

C) amplitude causedby motion of a source or receiver.

D) amplitude causedby a change in speed of sound.

4) If the speed of sound is 1100 feet per second and a tuning fork oscillates at 440 cycles per second, what is the wavelength λ of the sound produced?

A) 0.4 foot B) 2.5 feet C) 4.4 feet D) 11 feet

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5) On a day when the speed of sound in air is 340 m/s, a lightning bolt is observed and the resultant thunderclap is heard 5 seconds afterwards. About how far away was the lightning bolt?

A) 1020 m B) 170 m C) 1700 m D) 680 m

6) You hear a musician playing a series of notes of increasing frequency. As the frequency increases, the wave speed

A) increases.

B) decreases.

C) stays thesame.

7) Suppose an audible sound wave were being produced at a frequency of 800 cycles per second. If the frequency were doubled, the sound would become

A) softer.

B) louder.

C) lower in pitch.

D) higher inpitch.

8) Jim the meteorologist has predicted fair weather all day but sees flashes of lightning followed by rolls of thunder. To calculate the distance to the lightning bolt, Jim should measure the time between the instant he first sees a lightning flash and the

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A) instant the lightning flash is over.

B) instant he hears the beginning of the next thunder roll.

C) instant he hears the middle of the next thunder roll.

D) instant he hears the end of the next thunder roll.

E) instant he sees the beginning of the next lightning flash.

9) As a wave passes from one medium into another, it often happens that its speed increases with no change in frequency. Under these circumstances, the wavelength

A) increases.

B) decreases.

C) stays thesame.

10) Two musical strings have the same length and tension, but string A has one fourth the mass of string B. The speed of a wave on string A is

A) one fourth the speed of a wave on string B. B) one half the speed of a wave on string B. C) the same as thespeed of a wave on string B. D) twice the speedof a wave on string B. E) four times thespeed of a wave on string B.

11)

The pitch of a sound is determined primarily by its

A) frequency.

B) speed.

C) duration.

D) amplitude.

12)

To change the fundamental frequency of a guitar string, you can

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A) use somethingother than a pick.

B) strum it over the sound hole.

C) do nothing shortof using a completely different guitar.

D) make it shorter, by pressing a finger on the string.

13)

Which of these lists is in order of increasing wavelength?

A) second harmonic, third harmonic, fourth harmonic B) first harmonic, second harmonic, fundamental C) third harmonic, second harmonic, first harmonic D) first harmonic, second harmonic, third harmonic

14)

The principle of superposition tells us that, if two waves cross paths,

A) the amplitude isthe sum of the individual amplitudes.

B) the wavelength isthe sum of the individual wavelengths.

C) the frequency isthe sum of the individual frequencies.

D) the speed is the speed of the faster wave.

15) A musical tone is coming from a loudspeaker. If a second loudspeaker nearby were to start playing exactly the same tone, the sound would

A) get louder everywhere.

B) get softereverywhere.

C) stay the sameeverywhere.

D) get louder insome areas and get softer in others.

16) A guitar is perfectly tuned. The tension on its strings is then increased. Which of the following is true?

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A) The frequencies of sounds from the guitar are higher than before.

B) The wavelengths of sounds from the guitar are longer than before.

C) The speed of sounds from the guitar is larger than before.

D) The amplitudes of sounds from the guitar are larger.

17)

When a wave reflects from a stationary boundary,

A) the frequencyincreases.

B) the frequencydecreases.

C) the frequency isunchanged.

18) When a wave crosses from one medium into another in which the wave speed is lower, the frequency is unchanged. The wavelength

A) increases.

B) decreases.

C) stays thesame.

19) Suppose an audible sound wave were being produced at a frequency of 800 cycles per second. If the amplitude were doubled, the sound would become

A) louder.

B) softer.

C) higher inpitch.

D) lower inpitch.

20)

Which of the following is a longitudinal wave?

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A) a sound wave in a gas B) a wave on string under tension C) a light wave D) All of these choices are correct.

E) None of these choices are correct.

21) Imagine you are holding a long rope under tension attached to a distant support. You can generate periodic waves by shaking the end up and down. Changing which of the following will least affect the velocity of waves along the string?

A) tension B) mass per unit length of rope C) frequency D) None of these choices affect the wave speed.

22) Suppose the velocity of waves on a particular rope under a tension of 100 N is 12 m/s. If the tension is decreased to 25 N what will be the new velocity of waves on the rope?

A) 48 m/s.

B) 24 m/s.

C) 18 m/s.

D) 12 m/s.

E) 6 m/s.

23) Waves on a particular string travel with a velocity of 10 m/s. A high-speed photograph shows that successive peaks are 0.40 m apart along the string. The frequency of the waves is

A) 5 Hz B) 10 Hz C) 15 Hz D) 20 Hz E) 25 Hz

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24) On a day when the speed of sound in air is 340 m/s, what will be the wavelength of sound of frequency 227 Hz?

A) 227 m B) 3.0 m C) 1.5 m D) 0.67 m E) 0.33 m

25) Consider possible standing wave patterns for a string fastened at each end. Discussion in the text shows that there is a

A) minimum possible wavelength.

B) maximum possible frequency.

C) maximum possibleamplitude.

D) maximum possiblewavelength.

26) An organ pipe of length 3.0 m has one end closed. The longest and next-longest possible wavelengths for standing waves inside the pipe are

A) 6 m and 3 m.

B) 12 m and 6 m.

C) 12 m and 4 m.

D) 9 m and 6 m.

E) 3 m and 1.5 m.

27) A string is held taut between two supports 2.0 m apart. The longest and next-longest possible wavelengths for standing waves are

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A) 4 m and 2 m.

B) 6 m and 3 m.

C) 8 m and 4 m.

D) 16 m and 5.3 m.

28) The speed of electromagnetic waves in air is 3.0 × 108 m/s. What is the wavelength of FM radio waves having a frequency of 6.0 × 108 Hz?

A) 0.333 m B) 0.5 m C) 1.0 m D) 3.0 m E) 6 m

29) A fast train approaches a car waiting at a grade crossing and sounds its horn. A person in the car will notice that, compared to what it would be if the train were at rest, the horn sound's

A) wavelength appearsto be the same.

B) wavelength appearsto be longer.

C) frequency appears to be lower.

D) frequency appearsto be higher.

30)

A harmonic wave has

A) another wave nearby, so as to create harmony.

B) a closecorrespondence to simple harmonic motion.

C) to be a sound wave.

D) a higher speedthan a noise wave.

31) Captain Ahab notices that the waves passing the anchored Pequod are 10 feet from crest to crest, and that each minute 4 crests pass. The wave speed is

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A) 80 feet perminute.

B) 40 feet perminute.

C) 20 feet perminute.

D) 5 feet perminute.

32) A vibrating guitar string has exactly one antinode in the middle of the string and two nodes at the end. You have produced an oscillation of the string at its

A) fundamentalfrequency.

B) first harmonic frequency.

C) second harmonic frequency.

D) third harmonic frequency.

33) A standing wave is set up on a string so that it has 7 nodes (including the ones at either end). If you start at the central node and move exactly two wavelengths in either direction, you will wind up at

A) a node.

B) an antinode.

C) neither a node nor an antinode but still on the string.

D) somewhere off the string.

34) End A of a Slinky is held motionless near the ceiling. End B is held on the floor so that there is a slight stretch. End B is quickly rotated one half turn about the axis of the Slinky and then returned to its original position, so as to "twist" and then "untwist" the coils. The wave so produced is a

A) longitudinal wave.

B) transverse wave.

C) standing wave.

D) None of these choices are correct.

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35) An organ pipe makes a sound that has a frequency of 450 Hz when the temperature is 20°C. If the temperature is ten degrees colder the wavelength of sound produced in the pipe will

A) get longer.

B) stay the same.

C) get shorter.

D) It is not possible to tell without more information.

36) When playing tennis, if you hit the ball off of the top end of the racket, an uncomfortable standing wave vibration is produced in the racket. This wave is

A) longitudinal.

B) transverse.

C) both longitudinaland transverse.

D) neitherlongitudinal nor transverse.

37) Two waves approach each other as shown. When they completely overlap, the resulting wave will look like

A) B) C) D)

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38) Human hearing is most sensitive around 2500 Hz. If the speed of sound is 340 m/s, what is the wavelength of this sound?

A) 0.14 m B) 7.4 m C) 340 m D) 2160 m

39) When two strings of equal length on a guitar are played, two different pitches are heard.

Comparing the waves on the lower pitch string to the higher, the waves on the higher pitch string have

A) a largerperiod.

B) a largeramplitude.

C) a shorterwavelength.

D) a higherspeed.

40) A tuning fork with a frequency of 512 Hz is used to tune a violin. When played together, beats are heard with a frequency of 4 Hz. The string on the violin is tightened and when played again, the beats have a frequency of 2 Hz. The original frequency of the violin was

A) 508 Hz. B) 510 Hz. C) 514 Hz. D) 516 Hz.

41)

Sound is produced by a pipe that is closed on one end. The standing waves must have

A) just one node in the pipe.

B) at least one nodein the pipe.

C) at most oneantinode in the pipe.

D) no antinodes in the pipe.

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42) You have a set of 14 metal weights strung together by nylon fishing line at equal intervals. Each has a weight of 0.20 N. You suspend this array from the ceiling.

Which part of the array has the greatest tension in the fishing line?

A) above weight 1 B) between weights 1 and 3 C) exactly at weight 7 D) just above weight 14

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43) You have a set of 14 metal weights strung together by nylon fishing line at equal intervals. Each has a weight of 0.20 N. You suspend this array from the ceiling and then observe waves travel up and down by shaking it.

The wave seems to move more rapidly at the top, near weights 1-3. This is because

A) gravity iscancelled by tension, so net force is zero.

B) weight 14 isbalanced by no other weight, but weight 1 is balance by 13 others below it.

C) there is moretension in the fishing line near weights 1-3 than down by weight 14.

D) the amount of mass per centimeter is higher toward the top, near weights 1-3.

44) To excite the second harmonic in a jump rope, you have to change the frequency from the fundamental. The new frequency must be

A) larger.

B) smaller.

C) the same as the fundamental frequency, but you'll need a larger wavelength.

D) the inverse of the fundamental frequency.

45) Which general pattern holds for various excited states in standing waves on a rope or string fixed at both ends?

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A) Where the nodes are, you also find two antinodes.

B) Guitars and violins have antinodes only in even numbers: 0, 2, 4, and so on.

C) More antinodes means shorter wavelengths.

D) Standing waves involve the interference of waves traveling in the same direction.

46) Blowing gently across the top of a soda pop bottle gives you a musical note at a certain fundamental frequency. This is most similar to

A) making a guitar string resonate at its fundamental.

B) an organ pipe.

C) a wind chime.

D) a telephone.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

47) An antinode in a standing wave is the location that appears to (describe behavior) from equilibrium.

48)

The number of cycles of a periodic wave passing a point in space per second is called the of the wave.

49)

The product of the frequency of a periodic wave times its wavelength gives the of the wave.

50)

The distance between successive nodes for a standing wave pattern is the wavelength (give multiple or fraction).

51) will

Increasing the air temperature inside an organ pipe, neglecting any expansion of the pipe, the frequency of the fundamental tone.

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52)

Sound waves in water have a higher

53)

Constructive interference is a result of two waves arriving at a point .

54)

Mechanical wave motion is a phenomenon in which there is a transport of without net motion of the medium.

55)

Standing waves on a string produce a series of possible tones known as .

56) end.

An organ pipe open only at one end will have a displacement node at the

57) When fans do "the wave" at a sports stadium, it is a longitudinal) wave.

than sound waves in air.

(transverse or

58) The lowest frequency that can be made by a guitar string is called the words).

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Answer Key Test name: Chap 15_10e 1) B 2) C 3) A 4) B 5) C 6) C 7) D 8) B 9) A 10) D 11) A 12) D 13) C 14) A 15) D 16) A 17) C 18) B 19) A 20) A 21) C 22) E 23) E 24) C 25) D 26) C Version 1

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27) A 28) B 29) D 30) B 31) B 32) A 33) D 34) D 35) C 36) B 37) A 38) A 39) D 40) A 41) B 42) A 43) C 44) A 45) C 46) B 47) move 48) frequency 49) speed 50) 1/2 51) increase 52) speed 53) in phase 54) energy 55) harmonics 56) closed Version 1

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57) transverse 58) fundamental frequency

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CHAPTER 16 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) Which of the following colors has the shortest wavelength?

A) orange B) yellow C) green D) red

2)

Which of the following is not an electromagnetic wave?

A) light B) sound C) microwaves D) infrared E) x-ray

3)

Which statement is true?

A) Speed of light in air is lower than in glass.

B) Radio waves in the AM band are not electromagnetic waves.

C) Some electromagnetic waves will pass through walls that light cannot penetrate.

D) In air light travels much faster than radiation from a microwave oven.

E) Electromagnetic waves can't travel in perfect vacuum.

4)

The primary difference between infrared and visible light is that

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A) infrared travelsfaster than visible light.

B) they havedifferent wavelengths.

C) infrared does nothave a magnetic field associated with its electric field.

D) no materialscurrently known have the ability to reflect infrared.

E) they havedifferent amplitudes.

5) In Young's double-slit experiment, light was first passed through a narrow single slit before going on to the double-slits. The reason for the first slit was

A) to screen out allwavelengths except those in the visible light spectrum.

B) to reduce the brightness of the light so the interference pattern could be seen.

C) to polarize the light.

D) to ensure aconstant phase relationship between the interfering light waves.

6)

For visible light, which property of visible electromagnetic waves changes with color?

A) wavelength B) amplitude C) frequency D) amplitude and frequency E) frequency and wavelength

7)

The light from an incandescent bulb is composed of

A) only red, green,and blue light.

B) only red, yellow, and turquoise.

C) only red and blue.

D) all wavelengths in the visible portion of the electromagnetic spectrum.

E) None of these choices are correct.

8)

When ultraviolet light reflects from a violet surface, we see

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A) red.

B) violet.

C) white.

D) black.

9)

The frequency of red light is

that of a green light.

A) greater than B) less than C) the same as D) greater than, the same as, or less than, depending on a source of light

10)

The frequency of blue light is

that of green light.

A) greater than B) less than C) the same as D) greater than, the same as, or less than, depending on a source of light

11)

Which two primary colors of light can be added to produce yellow?

A) green and magenta B) red and green C) blue and green D) red and blue E) pink and mauve

12) If a surface is illuminated by magenta light and the red is absorbed, then the color of the surface will appear as

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A) blue.

B) red.

C) yellow.

D) green.

13)

What primary color must be added to magenta light to produce white light?

A) red B) yellow C) blue D) magenta E) green

14)

The normal human eye can detect colors whose wavelengths range from 380 nm to about

A) 550 nm.

B) 600 nm.

C) 650 nm.

D) 700 nm.

15)

The daytime sky is blue, on sunny days, because the atmosphere

A) is most efficientat scattering red light.

B) absorbs blue light.

C) contains smallamounts of water vapor that give the air its blue color.

D) is more efficientat scattering blue light.

E) absorbs the redlight.

16)

Electromagnetic waves that travel through a vacuum are not

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A) longitudinalwaves.

B) transversewaves.

C) able to propagate, since there is no atmosphere.

D) oscillating.

17)

If the only light present is yellow, what color will a blue sweater appear to be?

A) black B) white C) blue D) yellow E) green

18)

The evening sunsets are reddish orange because the atmosphere

A) absorbs bluelight.

B) is more efficientat scattering blue light.

C) absorbs the redlight.

D) contains smallamounts of red dust that give the air its red color.

E) is most efficientat scattering red light.

19)

EM waves tend to be scattered the most by an object that is

A) magnetic.

B) a liquid.

C) reflective.

D) conducting.

E) about the samesize as the wave.

20) When you look at a white light through a blue piece of glass, you observe blue light. This means that the blue glass

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A) absorbs all of the blue light.

B) reflects all of the blue light.

C) transmits onlythe blue light.

D) transmits allcolors except blue.

E) transmits only cyan and magenta.

21) A property of electromagnetic waves that makes them different than other kinds of waves such as sound or water waves is that

A) they aretransverse waves.

B) they do not require a medium to propagate through.

C) their speed can change when moving in different media.

D) they have many possible wavelengths.

22) A common property of all waves is the relationship between the speed (v), the wavelength (λ), and the frequency of the wave (f). The correct equation for this relationship is which of the following?

A) λ = vf B) f = vλ C) v = f/λ D) v = fλ

23)

The correct value for the speed of light in air is A) 3 × 105 km/h.

B) 3 × 108 m/s.

C) 3.0 × 105 m/s.

D) 1.86 × 105 miles/h.

E) 1.86 × 105 feet/s.

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24) Under the correct conditions, two light waves can produce regions of reinforcement and regions of cancellation. This phenomenon is known as

A) interference.

B) reflection.

C) polarization.

D) refraction.

25) Two light waves combine and produce a region of darkness. Which of the following must be true in that region?

A) The waves were unpolarized.

B) The waves came from the same source.

C) The waves had different wavelengths.

D) The waves were a half-wavelength out of phase.

26) A beam of orange light illuminates two slits that are closely spaced. The resulting intensity pattern is a series of bright and dark fringes. What happens to the intensity pattern if we now change to blue light?

A) The series of bright and dark fringes changes to circular fringes.

B) The series of bright and dark fringes spreads out.

C) The series of bright and dark fringes gets closer together.

D) The series of bright and dark fringes disappears.

E) Nothing changes.

27) A thin layer of oil floats on a water puddle. An observer sees a colored pattern. This happens because

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A) two surfaces each transmit some light and reflect some light.

B) oil always does this, even if it is not on water.

C) water transmits light and never reflects light.

D) sunlight's frequency range shifts to infrared at the boundary of water and oil.

28) A piece of ordinary glass transmits about 92% of the visible light incident on the glass.

The transmittance of the glass can be increased by

A) increasing the intensity of the incident light.

B) applying an anti-reflective coating to both sides of the glass.

C) slightly tilting the glass with respect to the light beam.

D) making the glass thicker.

29)

Which of the following waves exhibit interference?

A) sound, water, and light B) only sound C) only water D) only light E) None of these choices are correct.

30) When a beam of light passes through a narrow slit we can observe some light in the "geometrical" shadow of the slit. This light arrived by the process of

A) interference.

B) reflection.

C) refraction.

D) diffraction.

31)

The diffraction of light by the pupil of the eye limits

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A) the colorresponse of our eyes.

B) the ability ofour eyes to resolve very fine details.

C) our peripheralvision.

D) our ability tosee in the dark.

32)

A common use of a diffraction grating is to

A) split light into different polarizations.

B) focus light ontothe retina.

C) separate lightinto its separate wavelengths.

D) reflect lightinto a different direction.

33)

The polarization of a light wave is determined by the direction

A) of theoscillating electric field.

B) of the light'svelocity.

C) of thefluorescent tube used as a light source.

D) perpendicular toboth the electric and magnetic fields.

34)

One common way to polarize a beam of light is to

A) filter out the longest wavelengths of the spectrum.

B) filter out the shortest wavelengths of the spectrum.

C) slow it down using a piece of glass.

D) use a sheet of Polaroid material.

35)

A beam of "unpolarized" light

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A) does not have anypolarized waves.

B) contains a singlelight wave with a fixed polarization direction.

C) can be polarizedby reflecting it from a flat surface.

D) has apolarization direction that is constantly rotating.

36)

Polaroid sunglasses are designed to transmit primarily

A) light other thanblue.

B) horizontallypolarized light.

C) verticallypolarized light.

D) refracted waves.

E) longitudinallight waves.

37) The leaves of an oak tree are green and those leaves use light to help the tree grow. If the tree were exposed only to green light

A) it would grow more quickly because green light is used by the tree.

B) the growth rateof the tree would not change.

C) it would not growwell because the tree does not use much green light compared to otherwavelengths.

D) the growth rate would depend on how hot the green light was.

38) If a person has a shiny nose, applying powder will remove the shine without reducing the amount of light reflecting from the nose. This is an example of

A) polarization.

B) diffraction.

C) specularreflection.

D) diffusereflection.

39)

When you see your shadow on a sunny day, it has a fuzzy edge. This is

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A) not caused bydiffraction because the wavelength of visible light is too small to producevisible diffraction around a person.

B) not caused bydiffraction because diffraction only occurs for openings, not objects blockinglight.

C) an example ofdiffraction.

D) not caused by diffraction because there are too many wavelengths in sunlight to see the effect.

40)

When diffraction of light occurs with a single slit,

A) the interferencefringes have the same brightness as the central bright spot.

B) a number ofinterference fringes are produced around the central bright spot.

C) a central brightspot with one dimmer spot on each side can be seen.

D) only oneinterference fringe can be seen.

41)

When unpolarized light passes through a polarizing filter,

A) all the light passes through and remains unpolarized.

B) all the light passes through and is now polarized.

C) it is completelyabsorbed by the filter.

D) about half thelight passes through and remains unpolarized.

E) about half thelight passes through and is now polarized.

42) Which of the following types of radiation diffracts most when it passes through a diffraction grating?

A) blue B) violet C) yellow D) red

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43) Radio waves have light.

wavelength and

frequency relative to visible

A) longer;larger B) longer;smaller C) shorter;larger D) shorter;smaller

44) Ultraviolet light has light.

wavelength and

frequency relative to visible

A) longer;larger B) longer;smaller C) shorter;larger D) shorter;smaller

45)

Prisms and diffraction gratings can both

A) invert a light ray's frequency and wavelength.

B) change sunlight into a single color.

C) slow down lightto a few meters per second, if used back-to-back.

D) break theincoming light beam into its constituent colors.

46) An unpolarized beam of light of a single pure color can be split apart into two separate beams by using

A) a birefringent material like calcite.

B) the human retina.

C) metal-ceramic inversion.

D) a thin layer of oil.

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FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

47) Magenta, yellow, and cyan are the colors used in color mixing.

48)

The light-sensitive cells in our eyes that allow us to see color are called

49)

Infrared waves have a

50)

When green light shines on a cyan shirt, the color

.

wavelength than microwaves.

is seen.

51) When white light shines through a diffraction grating, the blue fringes are the central bright spot than the red fringes.

52)

When light reflects from mirrors we see a

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Answer Key Test name: Chap 16_10e 1) C 2) B 3) C 4) B 5) D 6) E 7) D 8) D 9) B 10) A 11) B 12) A 13) E 14) D 15) D 16) A 17) A 18) B 19) E 20) C 21) B 22) D 23) B 24) A 25) D 26) C Version 1

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27) A 28) B 29) A 30) D 31) B 32) C 33) A 34) D 35) C 36) C 37) C 38) D 39) A 40) B 41) E 42) D 43) B 44) C 45) D 46) A 47) subtractive 48) cones 49) shorter 50) green 51) closer to 52) specular

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CHAPTER 17 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) When light enters a medium with a higher index of refraction it

A) is absorbed.

B) is bent away from the normal.

C) is bent towards the normal.

D) continues in the same direction.

2)

Light is refracted as it crosses the interface between two different media because

A) it changesfrequency.

B) it losesenergy.

C) it changesspeed.

D) it becomespolarized.

3)

When light is reflected from a smooth, plane mirror

A) the angle ofreflection is the same as the angle of incidence.

B) the light ischanged to a lower frequency.

C) most of the lightis scattered into multiple directions.

D) the wave characteristics are predominant.

4)

The image produced by a single diverging lens will ALWAYS be

A) erect andvirtual.

B) erect andreal.

C) at infinity.

D) inverted andvirtual.

E) inverted andreal.

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5)

A converging lens

A) always has twocurved surfaces.

B) always has a realimage.

C) refracts alllight toward the focal point.

D) is thicker in the center than the edges.

6)

Which of the following lenses is a diverging lens?

A) A B) B C) C

7)

Light from the sun passes through a converging lens and forms an image at

A) infinity.

B) the center of thelens.

C) the focalpoint.

D) the center of curvature of the lens.

8)

A plane mirror will always produce a

A) virtual, invertedimage.

B) real, erectimage.

C) virtual, erectimage.

D) real, invertedimage.

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9)

A shaving mirror and a make-up mirror both magnify the image. Thus, these mirrors are mirrors.

A) plane B) concave C) convex

10)

The focal length of a glass lens depends on

A) the curvature of the surface of the lens.

B) the index of refraction of the glass.

C) the intensity of the light passing through the lens.

D) both the index ofrefraction of the glass and the intensity of the light passing through thelens.

E) both thecurvature of the surface of the lens and the index of refraction of theglass.

11)

The cornea of the human eye is an example of a

A) converging mirror.

B) converginglens.

C) diverginglens.

D) convexmirror.

12)

The unaided nearsighted human eye focuses light from a distant object

A) in front of theretina.

B) on theretina.

C) behind theretina.

D) acceptably but is too short for the focusing power of the cornea.

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13) The rearview mirror of an auto bears the legend "Objects in mirror are closer than they appear." This mirror is a mirror.

A) plane B) concave C) convex D) converging

14)

In the primary or inner rainbow, the

A) outer edge of the bow appears red and the inner edge appears blue or violet.

B) outer edge of the bow appears blue or violet and the inner edge appears red.

C) outer edge of the bow appears yellow and the inner edge appears green.

D) pot of gold is always at the left end.

15) A ray of light moves from air into water. Which path most accurately shows the refraction? {MISSING IMAGE}

A) A B) B C) C D) D E) E

16)

A rainbow shows separate colors of the spectrum because, at raindrop surfaces,

A) all colors arebent the same, hence the separation.

B) red light is bentmore than green light.

C) green light is bent more than blue light.

D) blue light isbent more than red light.

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17)

Convex (converging) lenses are worn by

A) a nearsightedperson to make rays from a nearby object diverge less strongly.

B) a nearsightedperson to make rays from a distant object diverge more strongly.

C) a farsightedperson to make rays from a distant object diverge more strongly.

D) a farsightedperson to make rays from a nearby object diverge less strongly.

18) Rays from a distant object do not diverge enough for a nearsighted person to focus; this can be corrected with a

A) diverging orpositive lens.

B) diverging ornegative lens.

C) converging orpositive lens.

D) converging ornegative lens.

19) fish,

A fish looks up through the smooth surface of the water at a bear directly above it. To the

A) the bear appears to be further away than it really is.

B) the bear appears to be closer to the point directly above the fish than it really is.

C) the bear appears to be exactly where it really is.

D) the bear cannot be seen due to total internal reflection.

20)

In normal use, the image seen through eyeglasses is

A) virtual.

B) real.

C) both virtual and real.

21) A ray of light in plastic reaches the edge of the plastic. The medium surrounding the plastic is air and the angle of incidence is larger than the critical angle. What will happen?

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A) The ray will refract out of the plastic, bending toward the normal line.

B) The ray will refract out of the plastic, bending away from the normal line.

C) The ray will experience total internal reflection, the angle of reflection being larger than the angle of incidence.

D) The ray will experience total internal reflection, the angle of reflection equaling the angle of incidence.

E) The ray will experience total internal reflection, the angle of reflection being smaller than the angle of incidence.

22)

A real image of a candle formed with a converging lens can be viewed on a screen placed

A) nowhere; that is,it can't be viewed on a screen at all.

B) at either focalpoint of the lens.

C) anywhere on theside of the lens from which the light emerges.

D) at a singleposition determined by the distance of the object and the construction of thelens.

23) A woman 1.6 m in height wants a plane mirror so that she can view her full height. The minimum vertical size of such a mirror is

A) 0.4 m.

B) 0.8 m.

C) 1.6 m.

D) 3.2 m.

E) impossible to say without knowing the viewing distance.

24)

A ray emerges from water (n = 1.33) into air. The light ray will

A) bend toward thenormal on the air side.

B) bend away fromthe normal on the air side.

C) emerge in air atthe same angle as in the water.

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25) Suppose a fish is observed below the surface of a lake. The distance the fish appears below the surface when looking down from above into the water (n = 1.33) is

A) greater than thefish's actual distance.

B) equal to the fish's actual distance.

C) less than thefish's actual distance.

26) A ray of light traveling in a calm pond strikes the surface at an angle of incidence which is 2° larger than the critical angle. This ray will

A) be refracted away from the normal to the surface in the air.

B) undergo totalinternal reflection and not enter the air at all.

C) be refractedtoward the normal to the surface in the air.

27) Which of the following optical elements used alone can produce a real image of an object?

A) convex mirror B) plane mirror C) negative lens D) concave mirror E) prism

28) An object is placed 10 cm in front of a concave mirror of focal length 30 cm. The image will be formed

A) 20 cm in front of the mirror.

B) 20 cm behind the mirror.

C) 15 cm in front ofthe mirror.

D) 15 cm behind themirror.

E) 0.05 cm behind the mirror.

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29) The image of an object placed 20 cm in front of a concave mirror of focal length 10 cm will be

A) virtual andinverted.

B) virtual anderect.

C) real andinverted.

D) real anderect.

30) An object is placed 10 cm in front of a diverging lens of focal length -15 cm. The image will be located

A) 0.167 cm in front of the lens.

B) 3.0 cm behind the lens.

C) 3.0 cm in front of the lens.

D) 6.0 cm in front of the lens.

E) 6.0 cm behind the lens.

31) A 1 cm object is placed 20 cm from a lens. The lens forms a real and inverted image of size 1.5 cm. What is the focal length of the lens?

A) 8.0 cm B) 12 cm C) 16 cm D) 20 cm E) 24 cm

32)

A nearsighted person requires glasses with lenses that are

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A) converging, tosee distant objects.

B) converging, tosee near objects.

C) diverging, to seedistant objects.

D) diverging, to seenear objects.

33)

In order for a telescope to produce a large magnification one would select lenses of

A) short focallength for the objective and long focal length for the eyepiece.

B) short focal length for both objective and eyepiece.

C) large focallength for both objective and eyepiece.

D) large focallength for the objective and short focal length for the eyepiece.

34) One difference between a microscope and a telescope is that the image formed by the objective is

A) real for themicroscope but virtual for the telescope.

B) real for both, but the image is enlarged for the microscope and reduced for the telescope.

C) real for both, but the image is reduced for the microscope and enlarged for the telescope.

D) virtual for themicroscope but real for the telescope.

35) A raindrop is doing its part to form a primary rainbow. Red and blue light enter near the top of the raindrop together from the sun. Both red and blue are reflected once at the back surface of the drop, but when the two rays emerge on the sunward side

A) the blue ray liesbelow the yellow ray and is more nearly horizontal than the yellow ray.

B) the red ray liesabove the blue ray and is more nearly horizontal than the blue ray.

C) the blue ray liesabove the red ray and is more nearly horizontal than the red ray.

D) None of these choices are correct.

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36) The speed of light in a certain type of glass is 30% slower than the speed of light in air.

What is the index of refraction for that type of plastic?

A) 1.33 B) 1.43 C) 1.5 D) 1.67

37) Light enters water (n = 1.33) from air. The incident light ray makes a 0.44° angle with the normal to the surface on the air side. What will be the angle made with the normal by the refracted ray on the water side?

A) nearly 90° B) 1.58° C) 0.33° D) 0.188°

38) If the image formed by a concave mirror is closer to the mirror than the object is, then, compared to the object, the image will be

A) smaller andinverted.

B) larger andinverted.

C) larger and erect.

D) larger andreal.

39) One ray that is useful in locating the image formed by a convex mirror is the ray that is incident on the mirror in a path directed toward the focal point. This ray is reflected

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A) directly backalong its incident path.

B) through thecenter of curvature.

C) on a path tangentto the mirror.

D) on a path parallel to the mirror axis.

40) A ray of light traveling through water passes through an air bubble. Which path does it take?

A) A B) B C) C D) D E) E

41) Two pools of water contain the same depth of water but one has a blue bottom and the other red. When looking into the pools from above,

A) the red bottompool appears deeper.

B) the pools appearto have the same depth.

C) the blue bottompool appears deeper.

D) it is notpossible to tell which will appear deeper from this information.

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42) Lenses can be used to focus sunlight to a small point to burn paper or dry brush. A person demonstrates this using their own eyeglasses as the lenses. From this you can tell that

A) the person isfarsighted.

B) the person isnearsighted.

C) the person iseither near- or farsighted but not both.

D) the person isboth near- and farsighted.

43) Rays of light traveling through different media hit the boundary between the media and the air. The angle of incidence is the same in each case. Which medium has the largest index of refraction?

A) A B) B C) C D) D

44) A beam of white light in air passes through the transparent object shown. Dispersion is observed to occur. From the diagram we can tell that {MISSING IMAGE}

A) the index of refraction is larger for red light than blue.

B) the index of refraction is larger for blue light than red.

C) the object acts as a converging lens.

D) the object behaves as a concave mirror.

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45) While looking into a mirror, you notice that the image of a tree is projected onto the back of a chair (the positions of the tree and image are shown here). You must be looking into

A) a planemirror.

B) a convex mirror.

C) a concavemirror.

D) a negative mirror.

46) The image viewed in a telescope is a magnified virtual image. To achieve this, a telescope must have

A) a positiveobjective lens with a small focal length.

B) a positiveeyepiece lens with a small focal length.

C) a negativeobjective lens with a large focal length.

D) a negativeeyepiece lens with a large focal length.

47) Fiber optics in a DVD player contain their light by employing total internal reflection.

Designers surround the pure glass core with another type of glass, called cladding, that has a different index of refraction from the core.

How should you select a cladding?

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A) Cladding must have a smaller index of refraction than the core.

B) Cladding must have a larger index of refraction than the core.

48) An iPod is 20 cm in front of a flat mirror. You see the reflected image and must refocus your eye, perhaps even take off your eyeglasses, because

A) your retina has adifferent curvature than the flat mirror.

B) the flat mirror replaces the object in a random direction.

C) the image isinverted but virtual.

D) the imagelocation is 20 cm behind the mirror.

49) Total internal reflection can occur when a light ray moves across a boundary between different materials in which direction?

A) parallel to the surface, but only if the ray is polarized B) exactly perpendicular to the surface, no matter what the indices of refraction C) from the material with the faster speed of light, into the material with the slower speed of light D) from a material with a slower speed of light to a material with a faster speed of light

50) A Jurassic dinosaur is approaching your vehicle and appears in the side-view mirror. It is larger than it appears in the mirror. This means that

A) its image size islarger than what the flat rearview mirror shows.

B) its image size issmaller than what the flat rearview mirror shows.

C) it is inverted and real.

D) it is a virtual image and inverted.

51)

The focal point of a lens is determined by

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A) the shape of thetwo surfaces of the lens.

B) the index ofrefraction of the lens material.

C) only the shape ifyou have a negative lens, otherwise only the index of refraction.

D) both shape andindex of refraction.

52) The image formed by a concave mirror when the object distance is greater than the focal length is always

A) real.

B) right side up.

C) virtual.

D) at a distance greater than the focal length.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

53) A curved mirror that cannot produce a real image of an object is .

54) When one observes a scratch on the bottom of a block of clear plastic, the scratch appears to be 2.5 cm below the top surface as viewed from above. The actual thickness of the plastic block is 3.0 cm. The index of refraction of the block is .

55) Glasses prescribed to correct a nearsighted eye will have a length.

56)

Parallel light incident on a positive lens will

57) A prism decomposes incident white light into its refraction.

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(sign) focal

as it emerges.

colors because of

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58)

The magnification produced by a plane mirror is

(sign and magnitude).

59) The objective lens of a high-power microscope will have a focal length and will be a (converging, diverging) lens.

60) Light passing from glass into air bends normal to the surface because it is traveling air.

(large, short)

(toward, away from) the (slower, faster) in the glass than in

61) An object is placed in front of a concave mirror. The object is farther from the mirror than the focal length of the mirror. The type of image reflected from the mirror is and the orientation of the image is .

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Answer Key Test name: Chap 17_10e 1) C 2) C 3) A 4) A 5) D 6) A 7) C 8) C 9) B 10) E 11) B 12) A 13) C 14) A 15) C 16) D 17) D 18) B 19) A 20) A 21) D 22) D 23) B 24) B 25) C 26) B Version 1

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27) D 28) D 29) C 30) D 31) B 32) C 33) D 34) B 35) C 36) B 37) C 38) A 39) D 40) A 41) A 42) A 43) D 44) B 45) C 46) B 47) A 48) D 49) D 50) B 51) D 52) A 53) convex 54) 1.2 55) negative 56) converge Version 1

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57) constituent 58) +1 59) [short, converging] 60) [away from, slower] 61) [real, inverted]

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CHAPTER 18 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) A chemical reaction is one in which

A) atoms getrearranged.

B) a substance getshot.

C) atomicnuclei change form.

D) atoms changemass.

2)

A true statement about atoms is that they

A) can emit radiationat frequencies only within the visible spectrum.

B) can emit radiationonly at specific frequencies.

C) all have the samenumber of electrons.

D) can emit radiationat any frequency.

3)

Lead (a solid) may be changed into mercury (a liquid) by

A) dissolving thelead in acid so that it loses enough mass to have the same mass as mercury.

B) grinding the leadto dust and then melting the dust.

C) heating the leadto extremely high temperatures.

D) None of these choices are correct.

4)

The maximum number of electrons allowed in the n = 1 shell of sodium is

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A) 2.

B) 4.

C) 6.

D) 8.

E) unlimited.

5)

The systematic arrangement of all known elements is known as

A) the angularmomentum chart.

B) the periodic tableof elements.

C) the chemicaldictionary of Arrhenius.

D) the metricconductance/reflectance table.

6)

Different atoms in the same column of the periodic table of elements

A) have a simple ratio of masses.

B) have equalmasses.

C) have identical chemical properties.

D) have similarchemical properties.

7) A diamond is the hardest mineral on Earth, yet it is mostly empty space because the carbon atoms are

A) not as closetogether as they should be.

B) held together byelectrical forces.

C) themselves mostlyempty space.

D) in perpetualmotion.

8)

When an atom has an electron removed, then its net charge is

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A) unchanged.

B) negative.

C) positive.

D) It is impossible to remove an electron from an atom.

9) If 42 g of nitrogen reacts completely with 9 g of hydrogen (atomic mass 1) to form ammonia (NH3), the atomic mass of nitrogen must be

A) 55.

B) 3.

C) 49.

D) 52.

E) 14.

10)

Which is the smallest entity in the following list?

A) atom B) electron C) molecule D) nucleus

11)

The Bohr theory of the atom made which of the following BOLD assumptions?

A) Electrons in certain orbits do not radiate electromagnetic waves despite being centripetally accelerated.

B) All atoms contain "special" electrons that do not radiate their energy.

C) The electrons in some orbits are paired so as to become stable.

D) The stable orbits are maximally occupied with electrons.

12)

The force that holds electrons within atoms is the

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A) gravitational force with the nucleus.

B) magnetic forcebetween the electrons.

C) electrical forcewith the nucleus.

D) nuclear force with the nucleus.

13)

A pencil has

A) no electric charges in it.

B) no nuclei in it.

C) electrons that are not attracted to nuclei.

D) enough positive charge in the nuclei to balance the negative charge of the electrons.

14)

A true statement about atoms is that they

A) are basicallyunstable.

B) all have the same number of electrons.

C) are big enough tobe seen by the eye.

D) consist mostly ofempty space.

15)

A true statement about the modern theory of light is that

A) light can onlybehave like a particle in atoms.

B) light can behavelike a wave or a particle depending on the situation.

C) light waves donot carry energy but photons can.

D) photons do nothave a frequency.

16)

One of the fundamental ideas in the development of quantum mechanics was that

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A) electrons andprotons are the only particles B) no two particlescan have the same energy.

C) all particleshave wave properties.

D) all particles are formed by the interaction of electromagnetic waves with mass.

17)

What is "uncertain" in the Heisenberg Uncertainty principle?

A) the time period of the wave describing the particle B) the value of the Planck's constant C) the energy of the particle when it has wave properties D) the value of the particle's position when the particle's momentum is known precisely E) the exact number of protons in the nucleus

18) Quantum mechanics has accurately described the regularities of the periodic table by assigning "quantum" numbers to predict the allowed energy levels. The true statement about quantum numbers is that

A) they describe theposition and charge of the electrons in the atoms.

B) no electrons in the world can ever have the same set of quantum numbers.

C) there are nevermore than 8 different sets of quantum numbers in an atom.

D) no two electronsin the same atom can have the same set of quantum numbers.

19)

Dalton developed

as one of the foundations for the atomic theory.

A) the law of supplyand demand B) the Principle ofEquivalence C) the Law ofDefinite Proportions D) Mach'sPrinciple E) the index of refraction

20)

Cathode rays produced in a gas discharge tube are

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A) gamma rays.

B) protons.

C) x-rays.

D) electrons.

E) alpha particles.

21) Which of the following is a form of natural radioactivity that will be deflected by a magnetic field?

A) x-rays B) gamma rays C) anode rays D) alpha rays

22) In the scattering of fast alpha particles by a thin foil of gold, Rutherford and his collaborators observed

A) alpha particlesinteracting with nuclei to produce beta rays and alpha particles moving equallyin all directions.

B) cathode raysemerging from the foil.

C) most of the alphaparticles bouncing straight back with very few passing through the foilundisturbed.

D) a very few alpha particles scattered through large angles with most undergoing very little scattering.

23) The idea that light could be emitted only in discrete chunks, or quanta, instead of in continuous amounts was first put forth to explain which of the following phenomena?

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A) blackbody radiation B) x-rays C) the spectrum of atomic hydrogen D) cathode rays E) radioactive decay

24) The transition in atomic hydrogen that gives the longest wavelength in the visible spectrum is

A) n = 4 to n =1.

B) n = 3 to n = 1.

C) n = 2 to n =1.

D) n = 4 to n =2.

E) n = 3 to n =2.

25) A series of transitions in atomic hydrogen that produce emissions all in the ultraviolet portion of the spectrum are those ending in the level

A) n = 1.

B) n = 2.

C) n = 3.

D) n = 4.

E) n = 5.

26) If h = Planck's constant, the frequency of light emitted when an atom makes a transition is equal to

A) the energy ofrevolution of the electron in its lowest energy orbit divided by h.

B) the energy gainedby the electron divided by h.

C) the energy lostby the electron divided by h.

D) the energy of revolution of the electron in its highest energy orbit divided by h.

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27) If h = Planck's constant, the de Broglie wavelength of a particle of linear momentum p and kinetic energy KE is given by which of the following formulas?

A) h/KE B) h.p C) KE/h D) h/p E) p/h

28)

Which of the following individuals did not directly contribute to quantum theory?

A) Heisenberg B) Roentgen C) Schrödinger D) Planck E) Einstein

29) The helium atom has one more electron than hydrogen. The chemical properties differ because helium

A) and hydrogen areequally reactive since chemical bonding has nothing to do with the number ofelectrons.

B) is more reactive,since it has two electrons that can form chemical bonds.

C) is much lessreactive, since its two electrons form a stable closed shell.

D) has neutrons in the nucleus.

30)

Strong x-ray beams can be produced when

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A) gamma rays movethrough a magnetic field.

B) alpha rays pass through a thin metal foil.

C) beta rays areabsorbed by bones.

D) cathode raysstrike a metal anode.

31) Some substances emit radiation without any need to expose the material to other energy sources. We call these substances

A) naturally radioactive.

B) noble gases.

C) rotationallysymmetric.

D) thermalequilibrium.

32) According to quantum mechanics, people should act like waves, too. The reason we do not exhibit wave properties is that our wavelengths are too small to observe. The reason the wavelengths of people are so small is that when finding the wavelength

A) Planck's constantis small and people masses are much larger than that.

B) Planck's constantis small and people move slowly.

C) Planck's constantis small and the mass of a person isn't very important.

D) Planck's constantis small and people move very fast.

33) According to the Bohr model of the hydrogen atom, electrons cannot get closer to the nucleus than a specific distance because

A) electrons are repelled by the nucleus.

B) electrons lack the energy to get close to the nucleus.

C) electrons must have an angular momentum in their orbits that is not equal to zero.

D) when electrons get to the lowest possible orbit, they run out of photons to radiate.

34)

Alpha rays are

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A) de Brogliewaves.

B) helium atomsstripped of their electrons.

C) a form ofelectromagnetic radiation.

D) fast-movingelectrons.

35) One of the patterns that shows up nicely in the periodic table is that similar chemical properties

A) correlate to the mass of each element on a row.

B) make greatbatteries, if you choose a metal from two separate rows.

C) exist on each diagonal, starting with hydrogen, then lithium, and so forth.

D) are displayed byelements in the same column.

36)

When an atom of sodium in the surface of the sun has two electrons removed, then

A) it has a negativecharge.

B) it is a positiveion susceptible to acceleration in solar magnetic fields.

C) it is a negatively charged rubidium atom.

D) it becomesaluminum.

37)

The energy of a photon is proportional to

A) its wavelength.

B) itspolarization.

C) itsfrequency.

D) its mass.

38)

Helium has chemical properties similar to

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A) boron.

B) hydrogen.

C) lithium.

D) neon.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

39) The form of radiation from naturally radioactive uranium that has the largest mass is rays.

40)

The energy of a photon is calculated from the product of the constant h times the .

41) In the Bohr model of the hydrogen atom the non-radiating orbits are determined by quantizing the (physical quantity).

42) The Bohr condition for determining the stable orbits in hydrogen can be explained in terms of for the electron (two words).

43) The Balmer series of spectral lines corresponds to transitions ending in a state of quantum number n= .

44) According to Heisenberg's principle, if one attempts to make a precise measurement of the linear momentum of a particle, he/she will get a large uncertainty in the determination of the of the particle.

45)

Cathode rays and

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are both streams of electrons.

11

46)

The electron was discovered by (two words).

47)

X-rays are

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waves of

(one name) in his study of

wavelength.

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Answer Key Test name: Chap 18_10e 1) A 2) B 3) D 4) A 5) B 6) D 7) C 8) C 9) E 10) B 11) A 12) C 13) D 14) D 15) B 16) C 17) D 18) D 19) C 20) D 21) D 22) D 23) A 24) E 25) A 26) C Version 1

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27) D 28) B 29) C 30) D 31) A 32) A 33) C 34) B 35) D 36) B 37) C 38) D 39) alpha 40) frequency 41) angular momentum 42) standing waves 43) 2 44) position 45) beta rays 46) [Thomson, cathode rays] 47) [electromagnetic, short]

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CHAPTER 19 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) The three types of nuclear radiation are

A) protons, electrons,neutrons.

B) electrical, strongnuclear, weak nuclear.

C) radiation,convection, conduction.

D) gamma, beta,alpha.

2)

The word "radioactive" means

A) an atomic nucleusabsorbs neutrons.

B) there issignificant interference between atomic radiation and radio reception.

C) there are nucleipresent which will spontaneously emit nuclear radiation.

D) an atomspontaneously captures an electron from a neighboring atom.

3)

The discovery of the neutron helped people understand

A) how two atoms ofthe same element can have different atomic masses.

B) why the nucleushas a positive charge.

C) how electrons areattracted to the nucleus.

D) why the nucleus ismuch more massive than the electrons in an atom.

4)

The number of protons in the nucleus of an atom determines

A) the half-life ofthe nucleus.

B) the density of thenucleus.

C) the atomicmass.

D) the number ofneutrons in the nucleus.

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5)

The "alpha" particle is

A) two electronsbound to two protons.

B) two protons boundto two neutrons.

C) an electron.

D) two electronsbound to two neutrons.

E) a photon.

6)

The "beta" particle is

A) an electron.

B) electromagnetic radiation.

C) two electrons bound to two neutrons.

D) a helium nucleus.

7)

A "gamma" ray is

A) an electron.

B) electromagnetic radiation.

C) two electrons bound to two neutrons.

D) a helium nucleus.

8)

During radioactive decay, the daughter element is always

A) more massive than the parent.

B) the same mass asthe parent.

C) less massive thanthe parent.

D) None of these choices are correct.

9)

When a nucleus undergoes alpha decay, the daughter element always has

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A) less charge thanthe parent.

B) the same atomicnumber as the parent.

C) more neutrons thanthe parent.

D) more electrons than the parent.

10)

A nucleus undergoes beta minus decay. Which of the following statements is true?

A) The daughterelement has more protons than the parent.

B) The daughterelement has fewer protons than the parent.

C) Both daughter andparent elements have the same atomic number.

D) The daughterelement has the same number of protons as the parent.

11)

The "half-life" of a large collection of radioactive nuclei is

A) the number of nuclei that decay in 1 second.

B) the number of nuclei that remain after 1 second.

C) larger for heavynuclei than for lighter nuclei.

D) the time for halfof the collection to decay.

12)

Which of the following mechanisms can change the half-life of radioactive nuclei?

A) increasing the number of nuclei in the sample B) extreme high pressure C) extreme high temperature D) None of these choices are correct.

13) A nucleus undergoes radioactive decay, emitting a gamma ray. Which of the following statements is true?

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A) The daughter nucleus has more neutrons than the parent.

B) A nuclear proton changes into an electron-positron pair.

C) Both daughter and parent nuclei have the same atomic number.

D) The daughter nucleus is more massive than the parent.

14)

What is the source of the energy released in nuclear reactions?

A) the binding of orbital electrons to the nuclear protons B) the conversion of mass to energy C) the conversion of nuclear kinetic energy to particle potential energy D) heat released during the radioactive decay process

15)

In nuclear fission,

A) a nucleus issplit into two less massive nuclei.

B) two heavy nucleiare induced to decay simultaneously.

C) high-energyparticles are released from a nucleus that is at rest.

D) a nucleus isbombarded with another nucleus in order to induce an alpha decay.

16)

The separation of different isotopes of a particular element can be difficult because

A) all isotopes aredangerous because of their radioactivity.

B) neutrons are sosmall.

C) chemicalreactions happen the same way for the isotopes.

D) the masses of theisotopes are the same.

17)

In a nuclear reactor, "chain reaction" refers primarily to

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A) an out-of-control explosion.

B) the process ofheating water to create steam to generate electric power.

C) the enrichment of uranium to make fuel for the reactor.

D) the process bywhich the fission of one nucleus causes other nuclei to undergo fission.

18)

The substance that comes from a nuclear reactor which is used to generate power is

A) enriched uranium.

B) high-pressuresteam.

C) radioactivematerials.

D) graphite.

19) is

A primary waste product of nuclear reactors that are designed for only power generation

A) enricheduranium.

B) graphite.

C) radioactivematerials.

D) high-pressuresteam.

20)

In nuclear fusion,

A) two smallernuclei combine to form a larger nucleus.

B) many radioactivenuclei decay at once.

C) a large nucleussplits into smaller fragments.

D) the temperatures required are so high that it has never been accomplished on Earth.

21)

The N14 nucleus consists of

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A) 14 neutrons.

B) 14 protons.

C) 21 protons and 7 electrons.

D) 7 protons and 7 neutrons.

22) Two nuclei have the same number of protons but different numbers of neutrons. We call these two nuclei

A) isotopes.

B) isobars.

C) atomic massunits.

D) ions.

23)

Energy released in a nuclear fission process is produced by

A) electrons movingfrom a higher energy orbit to a lower energy orbit.

B) the conversion ofsome charge to energy.

C) the conversion of gravitational potential energy into kinetic energy.

D) conversion ofsome mass to energy.

24)

In a decay of90Th232 by emission of an alpha particle, the daughter nucleus will be A) 92U232.

B) 90Th228.

C) 87Ac232.

D) 88Ra230.

E) 88Ra228.

25)

Generally, the number of neutrons present in nuclei that are fission fragments is the number of neutrons of corresponding nuclei of stable isotopes.

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A) less than B) equal to C) greater than

26) A deuterium nucleus and a tritium nucleus react to yield one alpha particle, a neutron, and energy. This is an example of a

A) chemicalreaction.

B) fissionreaction.

C) fusionreaction.

D) chainreaction.

27) A deuterium nucleus and a tritium nucleus react to yield one alpha particle, a neutron, and energy. For this reaction, the sum of the masses of reaction products after the reaction is the sum of the masses of particles before the reaction.

A) less than B) equal to C) greater than

28) In a modern light water reactor, the ratio of U235 to U238 in the nuclear fuel is typically in the approximate ratio of

A) 0.7%.

B) 100%.

C) 11%.

D) 3%.

E) 67%.

29)

The purpose of the moderator in a reactor is to

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A) slow neutronsdown so that they will be more likely to initiate fission reactions.

B) provide coolingfor the control rods.

C) reduce the numberof neutrons available for the chain reaction.

D) separate the nuclear fuel from the spent products of fission.

30)

Both conventional fossil fuel and nuclear power plants

A) produce wasteheat that can affect the weather or upset the ecology of rivers or lakes.

B) produce carbondioxide, which may increase global warming.

C) contribute to theproblem of acid rain.

D) produce hazardouswaste products that must be stored in isolation for thousands of years.

31) The primary reason that nuclear fusion has proven difficult to adapt for commercial power generation is that

A) the fuel isdifficult to purify.

B) the possible fuelis scarce.

C) the temperaturesinvolved are too low for efficient production.

D) nuclei repel eachother due to their positive charges.

32)

A sample of U235 that is below the critical mass will not sustain a chain reaction because

A) too many neutrons escape through the surface of the sample without initiating fission.

B) the inertia ofthe sample is too low for efficient fission.

C) nuclei repel each other due to their positive charges.

D) the heat producedby the spontaneous fission of some nuclei is insufficient.

33) The average U.S. citizen receives measurable radiation from man-made sources such as power plants, medical and dental X-rays, and consumer products. The radiation received from natural sources is

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A) about the same asthat received from artificial sources.

B) almostimmeasurable.

C) more than thatreceived from artificial sources.

D) measurable butless than that received from artificial sources.

34) Walther Bothe and Wilhelm Becker discovered a new kind of particle radiation in 1930.

The particle was later determined to be a neutron. Bothe and Becker generated neutron radiation by

A) heating nuclei toextremely high temperatures to boil the neutrons off.

B) using an isotopethat decays by emitting neutrons.

C) using electronsto attract protons away from the nucleus.

D) firing a beam ofalpha particles at a beryllium target.

35)

The Tokamak is a type of

A) moderator used inpressurized heavy water reactors.

B) experimentalfusion reactor.

C) nuclear reactorusing graphite as a moderator, such as the reactor at Chernobyl.

D) particleaccelerator.

36)

The number of neutrons in a stable isotope must

A) equal the numberof protons plus electrons.

B) equal the number of electrons.

C) equal the numberof protons.

D) None of the choices are correct.

37) Two atoms have the same number of neutrons but different numbers of protons. These two atoms

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A) will exhibitdifferent chemical properties.

B) are isotopes ofeach other.

C) have the samenumber of electrons.

D) have the sameatomic mass.

38)

In a nuclear fission reaction,

A) one nucleus splits into two equal halves.

B) one nucleussplits into two parts, neither daughter having a mass close to the parent.

C) one nucleussplits into two parts, one very small and one almost the same mass as theparent.

D) two nuclei combine to form a single, more massive nucleus.

39) A feature of the nuclear reactor at Chernobyl that contributed to the magnitude of the accident there was that

A) water was usedonly as a coolant, not a moderator.

B) plutonium couldbuild up quickly in the reactor.

C) the uranium fuelwas more highly enriched.

D) the reactor did not have control rods.

40)

In all nuclear reactions,

A) energy must beconserved.

B) the total number of protons plus neutrons must be conserved.

C) charge is notcreated or lost.

D) All of these choices are correct.

41) A piece of uranium can be made into nuclear explosive only after it is purified into uranium-235, because

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A) it has to besoldered with lead for safety.

B) the othernaturally occurring isotopes of uranium interfere with efficient chainreactions.

C) uranium-235 isthe heaviest isotope known to mankind.

D) beforepurification, the uranium-235 nucleus will not split apart.

42)

The atomic mass system is based upon

A) the mass ofuranium-238, since it is the heaviest element occurring in nature.

B) the mass of theneutron.

C) the mass ofliquid water.

D) the mass ofcarbon-12, a very common isotope of carbon.

43) The instability of uranium-235 compared to uranium-238, along with the relative stability of hydrogen compared to tritium, shows that the stability of a given nucleus depends upon

A) the speed ofelectrons orbiting the nucleus: more mass means more gravitational pull.

B) adding orsubtracting neutrons, which can change a stable isotope into an unstableisotope.

C) the mass: heaviernuclei are always less stable.

D) the number ofelectrons in the nucleus.

44) Momentum and energy from focused laser beams can be used in nuclear fusion. This is because

A) light cannot bemelted, so its pressure can confine the reaction.

B) light is notmagnetic.

C) light can alsofunction as a moderator, like graphite or water in a uranium reactor.

D) the wavelength oflight is small enough to penetrate each proton.

45)

Neutrons were discovered by James Chadwick by observing the behavior of

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A) gold atoms in a thin foil.

B) copper conducting electricity in the absence of a magnetic field.

C) carbon dioxidemolecules under high pressure.

D) the collision after-effects of protons emerging from paraffin.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

46) Suppose a radioactive isotope has a half-life of 2.0 hours. For an initial sample of 6400 nuclei, the number remaining after 6.0 hours is about .

47) To make a bomb based on the fission reaction work, one must at the time of detonation bring together an amount of fissionable material equal to or larger than the mass.

48)

The energy radiated by the sun has as its primary origin energy produced by reactions.

49)

Control rods are inserted into a nuclear reactor when you want the nuclear reaction rate to .

50) The was a particle predicted to exist long before it was observed because energy is not conserved in beta decays without it.

The nuclide93Np239 decays by emission of a negative electron. The daughter nucleus will 51) have an atomic number and a mass number .

52)

Materials that are used as moderators in nuclear power reactors are carbon (graphite) and .

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53)

The atomic mass unit is based on the mass of the

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Answer Key Test name: Chap 19_10e 1) D 2) C 3) A 4) B 5) B 6) A 7) B 8) C 9) A 10) A 11) D 12) D 13) C 14) B 15) A 16) C 17) D 18) B 19) C 20) A 21) D 22) A 23) D 24) E 25) C 26) C Version 1

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27) A 28) D 29) A 30) A 31) D 32) A 33) C 34) D 35) B 36) D 37) A 38) B 39) A 40) D 41) B 42) D 43) B 44) A 45) D 46) 800 47) critical 48) fusion 49) slow down 50) antineutrino 51) [94, 239] 52) water 53) carbon-12

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CHAPTER 20 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) At which of the following speeds would the effects predicted by special relativity be most obvious?

A) 1.11c B) 0.99c C) 0.50c D) 0.01c

2)

Which of the following is a postulate of special relativity?

A) The laws of physics are the same for all observers in uniformly moving frames of reference.

B) Physicists can make no measurements in a moving reference frame.

C) The color of light is the same for all observers.

D) The relative speed of two objects is the same for all observers.

3)

If the speed of light were infinite but the postulates of special relativity still held, then

A) any moving objectwould have infinite momentum.

B) time dilationwould be obvious at low speeds.

C) lengthcontraction would not occur.

D) objects couldhave negative kinetic energy.

4)

One of the strange consequences of special relativity is that

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A) forces that are not real can be felt by some observers.

B) people moving at high speeds will feel crushed by length contraction.

C) time can move backward.

D) two events may appear simultaneous to one observer but not another.

5) Consider the list of physical properties below. According to special relativity, which ones are dependent on the observer speed?

A) length B) energy C) time D) All of these choices are correct.

6) A stationary observer views the approach of a spaceship moving at a relativistic speed.

The observer knows the of the spaceship, as it moves past, is less than if it were stationary with respect to her.

A) mass B) height C) length D) density

7) According to the special theory of relativity, physical laws are the same in frames of reference which

A) accelerate.

B) move in circles.

C) move inellipses.

D) move at uniformvelocity.

8)

An object moving at a relativistic speed past a stationary observer appears to

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A) have lengthexpanded and have a faster clock.

B) have lengthcontracted and have a faster clock.

C) have lengthexpanded and have a slower clock.

D) have lengthcontracted and have a slower clock.

E) be completely normal.

9) Clocks in a moving reference frame, compared to identical clocks in a stationary reference frame, appear to run

A) slower.

B) at the samerate.

C) faster.

D) backward in time.

10) A neutron passes by Earth at relativistic speed. Earth scientists observe the process of the neutron decaying into a proton, an electron, and a neutrino. Compared to the same type of process on Earth, earthbound observers would say that the process in the moving neutron

A) appears to happenat the same rate.

B) appears to happenmore slowly.

C) appears to happenfaster.

D) No process in another reference frame can be observed.

11) A spaceship, moving away from the Earth at a speed of 0.9c, fires a light beam backward.

An observer on Earth would see the light arriving at a speed of

A) 0.1c.

B) more than 0.1c but less than c.

C) c.

D) more than c but less than 1.9c.

E) 1.9c.

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12) A spaceship moves over my driveway at a relativistic speed. I observe that my driveway is the same length as the ship. I then conclude that the rest length of my driveway is the rest length of the spaceship.

A) greater than B) the same as C) less than

13)

The equation E = mc2 means that

A) mass is really abundle of energy traveling at the speed of light.

B) mass and energy when combined travel at the speed of light.

C) mass and energy when combined travel at twice the speed of light.

D) energy is really mass traveling at the speed of light squared.

E) energy and massare different forms of the same thing.

14) that

One of the predictions of general relativity that was not predicted by special relativity is

A) length decreaseswith speed.

B) time dilates withspeed.

C) space is curvednear massive objects.

D) F = ma does not work for relativistic objects.

15) Suppose Joe is at rest and Moe is moving at almost the speed of light. Due to length contraction, Joe sees Moe's starship as only five inches long. What does Moe notice about his own starship?

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A) It is shorter but no fatter.

B) It is both shorter and fatter.

C) It appears to be normal to him.

D) It is longer and more massive.

16) If you were to travel at a speed close to the speed of light, you would notice which of the following?

A) Your mass has increased.

B) Your iPod plays music more slowly—everyone sounds like a baritone.

C) Your pulse rate has decreased.

D) You would notice all of the effects listed.

E) You would notice none of the effects listed because you are in an inertial frame.

17) Starship "Alpha" is traveling at 0.6c (γ = 5/4) with respect to the identical starship "Beta."

Each starship has rest length 10,000 m. A cook aboard the "Beta" measures the time the "Alpha" requires to pass by his window. What result should he get?

A) about 6 microseconds B) about 25 microseconds C) about 33 microseconds D) about 44 microseconds E) about 70 microseconds

18) Starship "Alpha" travels at 0.9c past an identical starship "Beta," which is at rest. Both a cabin boy on the "Alpha" and a cook on the "Beta" measure the time required for the other ship to pass by their respective windows. Who measures the longer time?

A) the cabin boy B) the cook C) Both measure the same time.

D) The measured times cannot be compared.

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19)

The term "relativistic" refers to effects that are

A) observed when speeds are near the speed of light.

B) noticed about amoving object.

C) observed whenobjects move backward in time.

D) measured bystationary observers only.

20) Einstein's special relativity is based upon two postulates. The most radical of the two postulates states that

A) the speed of light is finite.

B) the classicalvelocity addition formula still holds at relativistic speeds.

C) the speed oflight is the same for all observers in all inertial reference frames.

D) there is no ethersurrounding the Earth.

21)

A difference between the special and general theories of relativity is that

A) specialrelativity deals with accelerated systems.

B) generalrelativity deals with accelerated systems.

C) specialrelativity is valid only in stationary reference frames.

D) generalrelativity only deals with swiftly moving objects.

22) An airplane travels from east to west with a velocity 450 mi/hr relative to the Earth. At the same time the wind is blowing from west to east at 50 mi/hr. What is the speed of the plane with respect to the air?

A) 500 mi/hr B) more than 450 mi/hr but less than 500 mi/hr C) 450 mi/hr D) more than 400 mi/hr but less than 450 mi/hr E) 400 mi/hr

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23)

The purpose of the Michelson-Morley experiment was to

A) determine thevelocity of light.

B) detect possiblemotion of the Earth relative to the sun.

C) detect possiblemotion of the sun relative to the ether.

D) detect possiblemotion of the Earth relative to the ether.

24) A spaceship approaches the Moon, traveling at 0.5c with respect to the Moon. Its crew shines a laser at the Moon. The beam strikes a lunar mirror and is reflected back to the ship. The crew on the ship will measure the speed of the reflected beam to be

A) 2.0c.

B) 1.5c.

C) c.

D) 0.75c.

E) 0.5c.

25) Suppose Spider-Man throws a web that is 1.00 m long with a velocity of 0.8c (γ = 5/3) with respect to the Earth. What will be the length of web as observed by J. Jonah Jameson standing on the Earth?

A) 1.67 m B) 1.33 m C) 1.00 m D) 0.80 m E) 0.60 m

26) One of two identical twins becomes an astronaut, while the other becomes a real estate broker. The astronaut embarks on high-speed space travel and is gone for several years. Upon the astronaut's return, the two twins reunite and compare their physical appearances. The result will be that

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A) the real estate broker has aged less.

B) the astronaut hasaged less.

C) both have agedthe same.

27) If one could measure the exact mass of a biscuit while hot and then compare it to the exact mass of the biscuit when cold, the result would be

A) the mass of thehot biscuit is slightly greater.

B) the mass of thebiscuit is exactly the same in both cases.

C) the mass of the cold biscuit is slightly greater.

28) The Flash, a comic superhero, is able to run close to the speed of light. Two people, with synchronized watches, stand several kilometers apart and time the Flash as he runs a straight course. The Flash has his own stopwatch and uses it to independently time his run. The Flash also observes the speed at which the finish line moves toward him, and upon finishing his run he calculates the length of the course by multiplying this speed by the time on his stopwatch. Who measures (I) the Flash's proper time for the race, and who measures (II) the rest or proper length for the race?

A) Both the Flash and the two people measure (I) and (II).

B) Neither the Flash nor the two people measure (I) or (II).

C) The Flash measures (I) but the two people measure (II).

D) The two people measure (I) and Flash measures (II).

E) Only the Flash measures both (I) and (II).

29) Two identical clocks are made. One is placed on the surface of a massive planet, and the other is placed in interstellar space. Which runs faster?

A) Both clocks will run at the same rate.

B) the planet clock C) the space clock

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30) Two identical atomic clocks are made. One is placed in the foothills of the Rocky Mountains at the NIST in Boulder, Colorado, about one mile above the sea level, and the second is flown in a GPS satellite around Earth at about 17,000 mph. Which clock gets ahead of the other?

A) the clock in orbit B) Both clocks run at the same rate.

C) the Boulder clock

31) A student calculates the momentum of a body moving at a relativistic speed by multiplying the rest mass by the velocity. This gives a result for the momentum that is

A) too large.

B) correct.

C) too small.

32) A train has a rest length of 100 m. Traveling at a very high velocity, it goes through a tunnel of length 80 m. Observers located at both ends of the tunnel note that at one instant the train appears to exactly fit within the tunnel. What is the velocity of the train expressed in units of c?

A) 0.333c B) 0.50c C) 0.60c D) 0.80c E) 0.866c

33) Starship "Alpha" is traveling at 0.8c (γ = 5/3) with respect to the identical starship "Beta."

Each starship has rest length 10,000 m. The ship's engineer aboard the "Beta" measures the length of the "Alpha" as it passes by his window. What result should he get?

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A) 6,000 m B) 8,000 m C) 10,000 m D) 12,500 m E) 16,667 m

34) A starship "Alpha" travels at 0.8c past an identical starship, "Beta," which is at rest. Both an engineer on the "Alpha" and a scientist on the "Beta" measure the length of the other ship as it passes by. Who measures the longer length?

A) the engineer B) the scientist C) Both measure the same length.

D) The measured lengths cannot be compared.

35)

According to the postulates of special relativity

A) it is impossible for an object to move faster than the medium it is moving through.

B) the speed oflight as measured by a stationary observer is the same as the speed of lightmeasured by someone moving toward the light.

C) light can movefaster when it moves with the luminiferous ether.

D) Newton's laws donot apply for objects moving at high speeds.

36)

An inertial force can be felt by observers

A) at rest in anymedium.

B) moving much moreslowly than the speed of light.

C) in a vacuum.

D) whose referenceframe moves in a circle.

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37) that

The most important conclusion to be drawn from the Michelson-Morley experiment is

A) the speed of light is influenced by the direction of motion.

B) the Earth is notan inertial reference frame.

C) light does nottravel through a luminiferous ether.

D) the Earth's orbital speed around the Sun is constant.

38) Einstein performed thought experiments to understand the implications of the postulates of special relativity because

A) the speedsinvolved are too large to easily generate.

B) did not know how to build an apparatus that would test his ideas.

C) he could notcarry out the experiments alone and no other scientists would work withhim.

D) he was too poorto afford the necessary experimental apparatus.

39) Light takes 4.3 years to travel from Alpha Centauri (the star closest to the Sun) to the Earth. If a spaceship traveling near the speed of light were to make the same trip, the time to travel this distance as measured by the astronauts would be

A) longer than thelifespan of a human being.

B) less than 4.3years.

C) 4.3 years.

D) a little morethan 4.3 years.

40)

An object with a nonzero rest mass moving at the speed of light would have

A) no momentum.

B) time pass at aninfinitely fast rate.

C) infinitevolume.

D) infinite apparentmass.

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41) An object that appears green in empty space is placed near but not in a black hole. To an observer far from the black hole, the object would appear

A) red.

B) green.

C) blue.

D) brown.

E) black.

42) In an observation made in 1919 demonstrating the deflection of starlight due to gravity, light rays moving near bent to a slightly different angle.

A) a laser with the same frequency of light B) the Sun C) the Moon D) the Earth at its equator

43) A spaceship, moving toward the Earth at a speed of 0.9c, shines a green laser at Earth. An observer on Earth would see the light arriving at a speed of

A) c but at asmaller frequency.

B) c but at ashorter wavelength.

C) 1.9c and with ashorter wavelength.

D) more than c but less than 1.9c.

E) 0.1c and with aninverted frequency.

44) A spaceship, moving away from the Earth at a speed of 0.9c, shines a green laser backwards at Earth. An observer on Earth would see the light arriving at a speed of

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A) 0.1c and with an inverted frequency.

B) more than c butless than 1.9c.

C) c but at a shorter wavelength.

D) c but at asmaller frequency.

E) 1.9c and with a shorter wavelength.

45) A radar signal bounces off your car and back to the antenna of a policeman's radar gun, checking for speeders. The radar gun can tell your speed of approach by "listening" for and measuring

A) a reflectedsignal at a higher frequency.

B) a reflectedsignal at a lower frequency.

C) a reflectedsignal at the same frequency but polarized.

D) a reflectedsignal with zero frequency.

46) Black holes cannot be observed directly, because they emit no light. However, a scientist can hunt for black holes because

A) a black hole will reflect light.

B) a black hole can still emit electrons.

C) black holes cangravitationally influence the orbits of nearby stars, and those stars can beobserved.

D) magnetic fieldscause an emanation of thermal energy in the form of high-speed protons.

47) The proper time interval between two events is measured from the frame of reference of an observer present at both events. Therefore, the proper time measurement of the decay of a neutron is measured by

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A) an observer inthe national lab at Los Alamos or any other certified nuclear lab.

B) an observer atthe speed of light, relative to the neutron.

C) an observer who is emitting light at all frequencies.

D) an imaginaryobserver riding along with the neutron.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

48) The result of the Michelson-Morley experiment supports Einstein's postulate for the theory of relativity.

49) The decay of a sample of radioactive atoms is studied by observers moving in different ways. One moves at 0.8c, another at 0.5c, another at 0.25c, and one at speed zero with respect to the sample. The one with a speed of will measure the shortest half-life.

50) An inertial frame is one moving with (two words) with respect to the "fixed stars", i.e., with respect to the average position of all matter in the universe.

51)

Adding heat to a body will

52)

A black hole consists of a large

the mass of the body.

in a small space.

53) Observers in accelerating frames of reference can experience which would not be felt in non-accelerating frames.

forces

54) According to general relativity, it is impossible to distinguish between an accelerated frame of reference and .

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Answer Key Test name: Chap 20_10e 1) B 2) A 3) C 4) D 5) D 6) C 7) D 8) D 9) A 10) B 11) C 12) C 13) E 14) C 15) C 16) E 17) D 18) C 19) A 20) C 21) B 22) A 23) D 24) C 25) E 26) B Version 1

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27) A 28) C 29) C 30) A 31) C 32) C 33) A 34) C 35) B 36) D 37) C 38) A 39) B 40) D 41) A 42) B 43) B 44) D 45) A 46) C 47) D 48) second 49) zero 50) constant velocity 51) increase 52) mass 53) inertial 54) the effects of gravity

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CHAPTER 21 MULTIPLE CHOICE - Choose the one alternative that best completes the statement or answers the question.

1) One of the intriguing questions for scientists of many ages has been "What are the elementary particles?" Which of the following is not considered an elementary particle?

A) quark B) muon C) proton D) electron

2)

The best evidence for quarks comes from

A) particles seenoutside the nucleus with charge 1/3 the charge of a proton.

B) scatteringexperiments performed at very high energies.

C) the decay ofelectrons into quarks and mesons.

D) theories thatwould not make sense if quarks did not exist.

3)

The very first subatomic particle discovered was the

A) muon.

B) quark.

C) proton.

D) electron.

E) neutron.

4)

The result of a particle meeting its antiparticle will most likely be

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A) the release ofquarks contained in each particle.

B) the creation of a"black hole."

C) annihilation ofthe two particles and the release of photons.

D) the creation of anew particle with twice the mass of the original particles.

5)

One fundamental difference between a particle and its antiparticle is the

A) charge, if the particle has a charge.

B) number of quarkscontained in each particle.

C) mass.

D) spin.

6)

Which of the following is not a basic or fundamental force in nature?

A) electromagnetic force B) strong nuclear force C) gravitational force D) frictional force

7) According to current theory, which of the following elementary particles does not contain quarks?

A) protons B) mesons C) neutrons D) electrons

8) Which of the following fundamental forces is hardest for theorists to incorporate into an overall unified theory of nature?

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A) gravitational interaction B) strong interaction C) weak interaction D) electromagnetic interaction

9)

Which of the following is not evidence for the Big Bang?

A) the expansion of the universe B) the existence of protons and neutrons C) the background of microwave radiation D) the ratio of hydrogen to helium observed in stars

10) The farthest galaxies from the Milky Way appear to be receding from us at the rate of 76,000 miles/sec. An observer in one of these distant galaxies would consider our galaxy to be

A) one of the fewmoving galaxies in the universe.

B) standing still atthe center of the universe.

C) standing still butnot at the center of the universe.

D) moving at 76,000miles/sec and located at the center of the universe.

E) moving away at76,000 miles/sec.

11)

The greatest red shifts are observed for those galaxies that are

A) the brightest.

B) nearest ourgalaxy.

C) at the greatestdistance from us.

D) near our galacticequator.

12)

The oxygen atoms in Earth's atmosphere were created

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A) during the Big Bang.

B) when atoms first formed, about half a million years after the beginning of the universe.

C) by nuclear fusion in massive stars.

D) during the formation of the Earth.

13) According to the Big Bang theory, atoms would have likely begun to form after approximately

A) 10 billionyears.

B) 400,000years.

C) 1 year.

D) 3 seconds.

E) 0.5 second.

14)

Atoms of materials that are good conductors of electricity have

A) mostly protons;thus, the negative charges jump easily from atom to atom.

B) only electrons, and so these electrons are easily moved.

C) outer electronswhich are loosely bound and thus easily moved.

D) no electrons;thus, any that are given to them are easy to move about.

15)

The best electrically conducting elements are located

in the periodic table.

A) on the left sideor in the transition regions B) in the last twocolumns C) in the first tworows D) in the middlecolumns E) randomly

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16) There are several elements that we regard as semiconductors. The common property of these elements is that they have

A) electrons, whichare randomly organized about the nucleus.

B) no electronsbeyond a closed shell.

C) outer electronswhich cannot move.

D) four outerelectrons beyond a closed shell.

17)

The dominant charge carrier in a n-type semiconductor is the

A) neutron.

B) electron.

C) proton.

D) hole.

18)

Semiconductor elements are "doped" in order to

A) increase theirelectrical conductivity.

B) make them lesssusceptible to temperature changes.

C) eliminate thepossibility of incomplete bonds.

D) make themelectrically charged.

19)

The term "solid-state electronics" refers to

A) the use of transistors rather than vacuum tubes.

B) the increased useof metals in electronic devices.

C) the replacement ofpositive charges with electrons in devices.

D) our ability to nowuse solids to make electronic devices.

20)

The dominant semiconducting material now in use is

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A) germanium.

B) silicon.

C) carbon.

D) gallium.

21) All galaxies are expanding away from every other galaxy in the universe in a manner similar to

A) a tape recording that is played backwards at double speed.

B) a telephone that is on hold.

C) pancake syrup ona pancake on Saturday morning.

D) dots of ink on aballoon that is being inflated at a birthday party.

22) The gravitational interaction was the first force figured out by scientist Sir Isaac Newton.

However,

A) it is not afundamental force of nature, only a symptom of inertia.

B) it will never beincorporated into a "theory of everything" because it is an attractiveforce.

C) gravitation hasbeen the hardest force to unite with electroweak and strong nuclearinteractions.

D) until we candetect gravitational waves, it will remain a mystery.

23)

Superconductors are materials that

A) are metallic.

B) have noelectrical resistance.

C) can be easilymade into wires.

D) All of these choices are correct.

24)

To make an n-type semiconductor from silicon, one adds impurity atoms of

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A) oxygen.

B) cobalt.

C) fluorine.

D) gallium.

E) arsenic.

25)

A transistor consists of

A) a layer of p-type semiconductor.

B) a layer of n-type semiconductor.

C) a combination of 2 doped layers, p and n.

D) a combination of3 doped layers, such as n-p-n.

26)

Which of these elements is classified as a semiconductor?

A) aluminum B) chlorine C) germanium D) sodium E) arsenic

27)

The easiest way to remember which quarks make up a neutron is

A) a neutron is an inside-out proton: uud.

B) neutrons are all about u—three up quarks: uuu.

C) the neutron is a real "dud"—a down quark, an up quark, and another down quark: dud.

D) roses are red, violets are blue, neutrons are nosy but do not have u: ddd.

28) To operate properly, superconductors must be kept below a critical temperature. The highest critical temperature for currently available superconductors is about

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A) 300 K. B) 200 K. C) 100 K. D) 25 K. E) 10 K.

29) The standard model of particle physics predicts the existence of three families of elementary particles with four particles in each family. All of these particles have been confirmed experimentally except for the tau neutrino. Most physicists think the reason it has not been found is that

A) it likely doesnot exist.

B) no current particle accelerator can generate enough energy to create a tau neutrino.

C) it is associatedwith the tau particle and the tau is difficult to trap.

D) neutrinos arevery difficult to detect.

30) Galaxies that are far away from us have spectra that are redshifted more than galaxies that are closer to us. It is thought that the reason for this is that

A) we are at theedge of the universe and moving away from the center.

B) we are at thecenter of an expanding universe.

C) space itself isexpanding.

D) the stars in moredistant galaxies are older and cooler than those nearby.

31)

Without transistors, computers

A) would be muchlarger.

B) could not be easily programmed.

C) could not bemade.

D) could not usedigital logic.

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32)

Liquid crystals have the useful property that

A) they can behavelike liquid semiconductors and make computers more flexible.

B) they can changefrom a liquid state to a solid state instantly.

C) their transparencycan be changed by applying an electric field.

D) they are verystrong in one direction but very weak in another.

33)

A positron and its antiparticle, the electron, can annihilate each other and produce

A) high-energyphotons.

B) protons andantiprotons.

C) green electronsand anti-green electrons.

D) quarks andantiquarks.

34) For a few hundred thousand years after the Big Bang, atoms could not form. Electrons could not stay bound to protons or helium nuclei. However, eventually, atoms did combine when

A) there was enoughangular momentum that protons and electrons acquired spins.

B) the universe hadexpanded and cooled sufficiently.

C) the curvature ofspacetime increased by 50%.

D) the theory ofeverything became active.

35)

Adding a few impurity atoms, like arsenic or gallium, to a semiconductor can produce

A) gravitationalrepulsion of the impurity atoms, like the expanding universe.

B) abundant thermal inversion.

C) a significantincrease in mass, even though the impurity atoms are quite sparse.

D) useful changes in the conductivity.

36)

High-temperature superconductors are made of

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A) metallichydrogen.

B) noble gases likehelium layered with highly reactive gases like hydrogen.

C) ceramics withcopper, yttrium, barium, and oxygen.

D) 99.999% pure copper.

37)

A modern day device that does not need to have a computer chip built into it is

A) a cell phone.

B) a blood pressure meter.

C) an MP3 player.

D) a hand held calculator.

38) Two beams of particles can be made to collide head-on at the point where the reactions are studied, providing a larger collision energy than from collisions with a stationary target. This must be true because to calculate available energy

A) what counts is thevelocity of the particles relative to the Earth's rotation.

B) what counts is thevelocity of the particles relative to the distant stars.

C) actual velocitiesare more important than relative velocities.

D) actual velocitiesare less important than relative velocities.

39) The most accurate way of finding the distance to some very far away stars might be by observing

A) their orbiting planets.

B) their motion relative to nearby stars.

C) the variation in their position in the night sky on successive nights.

D) the rate of variation in their luminosity.

40)

Evidence that the universe is expanding is provided by Hubble's Law which states that

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A) the farther away astar is from us, the greater its velocity of recession.

B) the farther away astar is from us, the less its luminosity.

C) the farther away astar is from us, the less its velocity of recession.

D) the nearer to us astar is, the greater its velocity of recession.

41) Observations of the shift toward the red in stellar absorption spectra for stars in galaxies outside our own implies that

A) objects observedin the light of these stars will appear more blue than red.

B) these stars arepart of a rapidly spinning galaxy.

C) these stars areheaded toward us.

D) these stars arereceding away from us.

42) The reason that some bright objects appearing in photographs of distant objects in the night sky appear to be blurry is that

A) they are reallyother galaxies, collections of billions of stars.

B) they are really nearby objects that can appear to move relative to distant and dimmer objects much farther away.

C) they are exploding supernovae very near to the Earth.

D) they would really look blurry even if you were right next to them.

43)

In present day technology, a substance can become a superconductor

A) at temperaturesabove 0 Kelvin but less than 100 Kelvin.

B) only at absolutezero temperature.

C) at roomtemperature.

D) at a temperatureabove the boiling point of water.

44)

Transistors are most useful devices electronic devices because

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A) they are excellent conductors.

B) they are excellent insulators.

C) they are excellent signal amplifiers.

D) they are highly inductive.

45) Current technology is in the process of developing electronic circuit elements with distances between elements of only

A) picometers.

B) nanometers.

C) microns.

D) millimeters.

FILL IN THE BLANK. Write the word or phrase that best completes each statement or answers the question.

46) According to the Big Bang theory, ordinary matter did not exist in the first microsecond after the beginning. All the matter in the universe was a sea of .

47)

The proton is a member of the

family of particles.

48)

The spectra of stars in other galaxies show a Doppler shift of spectral lines toward the (color) end of the spectrum, thus providing evidence for the expansion of the universe.

49)

There are three

of elementary particles in the standard model.

50) Superconductors lose their superconducting property above their temperature.

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51) A hologram is produced from the beam.

of a reference beam and an object

52) A device that has a very small resistance to current flowing in one direction but very high resistance to current flowing in the opposite direction is a .

53) A proton, according to the present theory, consists of (number) down quark(s).

(number) up quark(s) and

54) To make a p-type semiconductor from silicon, one element that might be added as an impurity is .

55) Theories that attempt to unify the electromagnetic, weak nuclear force, and strong nuclear force are called .

56)

Galactic redshifts indicate the

57)

A tiny device containing many transistors, diodes, and resistors is a(n) .

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of the universe.

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Answer Key Test name: Chap 21_10e 1) C 2) B 3) D 4) C 5) A 6) D 7) D 8) A 9) B 10) E 11) C 12) C 13) B 14) C 15) A 16) D 17) B 18) A 19) A 20) B 21) D 22) C 23) B 24) E 25) D 26) C Version 1

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27) C 28) C 29) D 30) C 31) A 32) C 33) A 34) B 35) D 36) C 37) B 38) D 39) D 40) A 41) D 42) A 43) A 44) C 45) B 46) quarks 47) baryon 48) red 49) families 50) critical 51) interference 52) diode 53) [2, 1] 54) boron 55) grand unified theories 56) expansion Version 1

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57) integrated circuit

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