Next Generation Science Level 6 - Activity Book B

Science for the Next Generation

Science Gra d e Si x

Activity Book

B

Next Generation Science Next Generation Science is based on the United States Next Generation Science Standards (NGSS). The series consists of full-color textbooks and full-color activity books for Grades K to 6.

Next Generation Science engages students with a highly visual presentation of the disciplinary core ideas in the textbooks and places an emphasis on applying scientific knowledge using NGSS practices through numerous scientific investigations. Next Generation Science sees engineering as an essential element of science education and as such is tightly integrated into both the textbooks and activity books.

The Next Generation Science activity books include the follow features:

AB Activity

(c)

Activity 5.8

s

e st ecosystem. Describ found in a rainfore List two decomposers energy. how they obtain their

ystem Energy Flow in Ecos

em. Use all of the words flows through an ecosyst Describe how energy tion. in the box in your descrip decomposer energy sun consumer producer

1.

Activities and investigations related to concepts and topics covered in the Next Generation Science Textbook.

2.

m and Consider the organis

ms and Consider the organis

3.

st ecosystem. their roles in a rainfore

their roles in an arctic

ocean ecosystem.

Describe ocean ecosystem. ers found in an arctic le. (a) List two produc energy with an examp how they obtain their

Describe ocean ecosystem. ers found in an arctic le. (b) List two consum energy with an examp how they obtain their

e how st ecosystem. Describ ers found in a rainfore (a) List two produc with an example. they obtain their energy

(c)

e how st ecosystem. Describ ers found in a rainfore (b) List two consum with an example. they obtain their energy

found in an arctic ocean List two decomposers obtain their energy.

Describe how they

ecosystem.

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Engineer It!

Engineer 134It!

Design Your Own Spin-off!

The Solution

A spin-off is a technology or object that was initially developed for space exploration, but has resulted in new objects and products for use by people in everyday life. Spin-offs have lead advances in area such as health and medicine, transportation, clean energy, safety and computer technology .

Goes beyond inquiry by encouraging students to design, model and build to engineer solutions to defined problems.

Explain your solution to the problem.

Identify the space technology that will be used

Now it’s your turn to design your own spin-off! In small groups, identify a problem on Earth that could be solved with space technology.

Draw a Model Draw a labeled model of your

The Problem

Matter 1.

to show of matter. Draw Label the states state. particles in each

ss that take place Label the proce

4.

Review

Topical questions at the end of each chapter for formative assessment.

design.

Define the problem.

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Review

to solve the problem.

25 t of the arrangemen

of chemical e two examples

Provid

6.

e when it begins es in solid ice chang occur?

How do the particl begin to rature does this At what tempe

to melt.

e.

les of physical chang

Provide two examp

5.

2.

es state.

as matter chang

mean 7. What does it

change.

if a change made

sible? to matter is irrever

st mixtures.

Use the Venn

8.

are and contra diagram to comp

Homogeneous Mixture

Heterogeneous Mixture

e when it boils? es in water chang How do the particl begin to occur? rature does this At what tempe

3.

9.

tion separate a

How does distilla

water. solution of salt and

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Contents Unit 6 - The Universe

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Unit 7 - Matter

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Unit 8 - Forces

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Unit 9 - Work and Simple Machines

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Unit 10 - Electricity and Circuits

104

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Activity 6.1

Galaxy Classification 1. Galaxies come in a variety of shapes and sizes. Scientists classify galaxies into four main types – spiral, barred spiral, elliptical and irregular. Work in small groups and use your textbook or conduct research online to learn more about each type of galaxy.

Spiral Galaxy Flat, rotating disk of stars. Central Description: concentration of stars known as the bulge.

Size: Larger than irregular, smaller than elliptical Age: Range from 10 - 13.6 billion years old.

Shape: Flat disk with central bulge and spiral arms.

Abundance: Most common type of galaxy.

Barred Spiral Galaxy Spiral galaxy with a central bar-shaped Description: structure composed of stars.

Size: Larger than irregular, smaller than elliptical Age: Range from 10 - 13.6 billion years old.

Shape: Spiral with bar of bright stars along the center.

Abundance: Most common type of spiral galaxy 2

Elliptical Galaxy

Description:

Elliptical galaxies have an elongated

shape and lack a central bulge.

Size: Largest of the galaxies Age: Range from 10 - 13.6 billion years old.

Shape:

Elliptical with no bulge at the center

Abundance: Make up about 10 - 15% of galaxies.

Irregular Galaxy Contain the oldest stars. No definite Description: shape or central bulge.

Size: Usually smaller than other galaxies Age: Range from 10 - 13.6 billion years old.

Shape: No definite shape Abundance: Make up about 25% of galaxies.

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2. What type of galaxy is our own Milky Way? The Milky Way is a spiral galaxy.

3. What is the most common type of galaxy in the universe?

Spiral galaxies are the most common type in the universe.

4. What type of galaxy includes both the largest and smallest galaxies observed in the universe?

Elliptical galaxies include the smallest and largest galaxies in the universe.

5. Compare and contrast spiral and irregular galaxies using the Venn diagram below.

Spiral

most common type of galaxy has spiral arms and a bulge in the center

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Irregular

collection of gas, dust, stars, and other objects.

no definite shape make up about a quarter of all galaxies

Activity 6.2

The Big Bang 1. What did astronomers observe to conclude that the universe is expanding?

They observed that all objects in space are moving away from Earth.

2. What is the Big Bang?

A scientific theory that describes the origin of the universe. All matter and energy was once concentrated in a small area followed by a period of rapid expansion.

3. How long ago did the Big Bang occur?

13.8 billion years ago.

4. Why were there no stars or galaxies in the early stages of the Big Bang?

It was too hot for the elements that make stars and galaxies (hydrogen) to be formed.

5. What evidence is there that the universe continues to expand today?

Object continue to cool and move away from Earth.

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Activity 6.3

Brightness of Stars Plan and conduct an investigation that uses a model to demonstrate that the brightness of stars depends on their distance from Earth.

Materials List the materials you will use.

Procedure Write the steps you will take.

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Observations Record your observations in the space below.

Analyze and Interpret 1. What can you conclude about the brightness of light and the distance from the light source?

2. Use the findings from this activity to explain why stars appear faint in the sky even though they are as large and bright as our own Sun.

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Activity 6.4

The Sun 1. How far is the Sun from Earth in kilometers?

150 million kilometers 2. What benchmark do scientists use to measure distances in the solar system?

The average distance between the Earth and the Sun, which is 150 million kilometers or 1 astronomical unit (AU).

3. What are the main gases that make up the Sun? The main gases that make up the Sun are hydrogen and helium.

4. Describe the size and temperature of the Sun. The Sun has a diameter of 1.3927 million km. The surface temperature o of the Sun is about 5,500 C.

5. What causes the light and heat produced by the Sun? The nuclear reactions that occur at the Sun’s core are what cause the light and heat produced by the Sun. 6. Which part of the Sun is the hottest?

The core.

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7. Draw a model of the Sun. Include the Sun’s different layers and label the parts with the words in the word box below. core radiative zone chromosphere photosphere convection zone corona

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Activity 6.5

Planet Comparisons 1. Choose any two inner planets and complete the comparison table below.

Planets

Appearance

Size Distance from the Sun Composition Length of a day Length of a year Number of moons Temperature

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2. Choose any two outer planets and complete the comparison table below.

Planets

Appearance

Size Distance from the Sun Composition Length of a day Length of a year Number of moons Temperature

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Activity 6.6

Asteroids, Meteoroids and Comets – Comprehension 1. Use your textbook to help you fill in the blanks. (a)

Asteroids

are large, rocky and

metallic

Sun

objects orbiting the . They range in size from just a few meters up to hundreds of kilometers. Most asteroids belt

orbit the Sun in an asteroid and Jupiter.

between Mars

(b) Craters observable on the moon were formed when

meteoroids rocky

struck its surface. A meteoroid is a small, or metallic object orbiting the Sun. Many

meteoroids form when smaller pieces. (c)

burn up

are broken up into

Earth’s

If a meteoroid enters

it becomes known as a

asteroids

atmosphere,

meteor

. Most meteors

completely before reaching the Earth’s

shooting stars

surface. The we see at night are most likely meteors burning up in the Earth’s atmosphere. (d) A meteor that doesn’t burn up completely and reaches the Earth’s surface is called a

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meteorite

.

(e)

Comets

are orbiting bodies comprised of frozen ice

gases, rock,

and dust. When a comet

passes close to the Sun, heat causes some of the ice to change to a gas. The gases form a

coma

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Sun in a belt of

Kuiper

called a

.

(f) Comets range in size from around to

tail

700

meters

kilometers. Many comets orbit the asteroids

and other objects called the

belt.

2. What must occur for a meteoroid to become a meteor?

A meteoroid must enter Earth’s atmosphere and then heat up due to atmospheric friction in order to become a meteor.

3. What must occur for a meteor to become a meteorite?

It must strike the Earth’s surface.

4. What is the Meteor Crater and how was it formed?

The Meteor Crater is a large crater in Arizona that was formed by the

impact of a meteor. Scientists believe the crater was created about 50,000 years ago.

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Activity 6.7

Solar System Crossword

Read the clues related to the solar system and complete the crossword on the opposite page.

Across 3. This ice giant has a faint ring system.

6. The furthest planet from the Sun. 7. This body was once considered a planet, but is now classified as a dwarf planet.

9. This inner planet is the smallest planet in the solar system.

12. There is a belt of these objects between Mars and Jupiter.

13. A meteoroid that enters the Earth’s atmosphere.

14. Many comets can be found in this belt beyond Neptune.

Down 1. This inner planet is the hottest planet in the solar system.

2. A planet famous for its beautiful ring system.

4. Our solar system’s very own star.

5. The largest gas giant.

8. This planet is often called the ‘Red Planet’.

9. The name given to a meteor that reaches the Earth’s surface.

10. The only planet in our solar system known to contain life.

11. An orbiting body comprised of frozen gases, rock, ice and dust.

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Activity 6.8

Exploring Objects in Space Materials • planet posters

• safety glasses

• measuring tape

• masking tape

• hand lens

• petroleum jelly

Procedure 1. Work in pairs. Mark out a distance of 5 m using the measuring tape and masking tape. You can do this in your classroom or outside.

2. Smear a thin film of petroleum jelly on the safety glasses and put them on. The safety glasses are a model of the atmosphere when observing a planet with a telescope from Earth.

3. Have your partner stand at the 5 m mark and choose a planet poster from the back of this activity book. Have them hold the poster up for you to observe.

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4. Record your observations by drawing a diagram of the planet and describing any features you can see.

5. Remove the glasses and take two steps towards the poster. You are now modeling observations from a space telescope that is orbiting Earth beyond the atmosphere. Repeat Step 4.

6. Move to an arm’s length from the poster and observe the planet with the hand lens. You are now modeling observations from a probe sent to perform a fly-by of the planet. Repeat Step 4.

7. Have your partner choose a new planet and repeat Steps 3 to 6.

8. Switch roles with your partner.

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Observations Draw and label the planet you observed at the three different stages.

Planet 1

Telescope from Earth

Telescope from space

Probe fly-by

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Planet 2

Telescope from Earth

Telescope from space

Probe fly-by

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Analyze and Interpret

1. Compare the observations you made modeling a telescope from Earth to those from a space telescope.

2. Compare the observations you made modeling a space telescope to those made from the probe fly-by.

3. List a disadvantage of observing objects in space with Earth-based telescopes.

Earth-based telescopes are subject to interference by the Earth’s atmosphere.

4. List an advantage of observing objects in space with space telescopes.

It is much easier to observe objects in space because there is no interference by the Earth’s atmosphere.

5. List an advantage of observing objects in space with probes.

Objects in space are able to be observed at a much closer distance than when using telescopes.

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Activity 6.9

Space Exploration – Comprehension 1. Use your textbook to help you fill in the blanks. (a) The first telescopes used to observe objects in space were

light

telescopes. These telescopes reflect or

refract magnify

light to objects to make them appear closer.

distant

(b) When viewing objects in space from Earth, light telescopes are subject to

(c)

interference

atmosphere Radio waves dishes

from the Earth’s

. telescopes are telescopes that detect radio given off by distant objects. Groups of are often used to focus the radio waves.

Radio telescopes do not experience Earth’s atmosphere.

interference

with the

2. Why are space probes the best way to collect the clearest images of space objects?

As the objects are able to be observed at much closer distances.

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Activity 6.10

Space Exploration Research Project Choose a space exploration achievement from the timeline on pages 24 and 25 of your textbook. Research the mission and complete the project on these pages.

Mission name: Launch date:

Mission duration:

Launch location:

Rocket used:

What were the objectives of the mission?

What were the key achievements of the mission?

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These are my favorite images from the mission.

What is an interesting fact about this mission?

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Engineer It!

Design Your Own Spin-off!

A spin-off is something that is developed from an earlier project. Developments in space technology have resulted in many new objects and products used by people in everyday life. Space technology spin-offs have led to advances in areas such as health and medicine, transportation, clean energy, safety and computer technology.

Now it’s your turn to design your own spin-off! In small groups, identify a problem on Earth that could be solved with space technology.

The Problem Define the problem.

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The Solution Explain your solution to the problem.

Identify the space technology that will be used to solve the problem.

Draw a Model Draw a labeled model of your design.

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Analyze and Interpret

1. Evaluate the effectiveness of your design.

List the ways it can be improved

2. How are the materials used in your design safe and suitable for their application?

3. Compare your spin-off design to that of another group in your class.

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Review

The Universe 1. Describe Earth’s place in the universe.

The Earth lies in the Milky Way galaxy. Within the galaxy is belongs to a collection of bodies orbiting the Sun which makes up the solar system.

2. Riley sister thinks there are billions of stars in our solar system.

Is she correct? Explain your answer.

She is incorrect. Our solar system consists of one star – the Sun.

3. What produces the light and heat given out by the Sun?

Nuclear reactions that take place at its core.

4. What is the distance from the Sun to Earth? Provide your answer in kilometers and astronomical units.

150 million kilometers. 1 astronomical unit.

5. Use the Venn diagram to compare and contrast the planets in our solar system.

Inner planets

Outer planets

smaller

orbit Sun

larger

made mostly of rock

spherical

made mostly of gas

Few or no moons

many moons

6. What is meant by a space technology spin-off? Provide one example.

A spin-off is when space technology is used in the development of Earth-based technologies.

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Activity 7.1

Mass and Volume In this activity, you will investigate if mass and volume change when a piece of modeling clay is reshaped.

Materials • modeling clay

• electronic scale

• graduated • paper towel beaker of water

Make a Prediction Do mass and volume change when modeling clay is reshaped?

Procedure 1. Work in pairs. Take a piece of modeling clay and roll it into the shape of a ball.

2. Place the ball of modeling clay on the electronic scale and record its mass.

3. Add water to the beaker up to a level that will completely submerge the ball of clay when it is placed inside. Record the volume of water in the beaker.

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4. Place the ball of clay in the beaker of water. The water level will rise.

Record the new volume of the water. Subtract the new volume from the original volume to calculate the volume of the clay. Record the volume of the clay.

5. Remove the clay from the water and dry it off with some paper towel.

6. Reshape the clay into your favorite animal. Then repeat Steps 2 to 5.

Observations Clay ball

Clay animal

Mass:

Mass: Water volume

Water & clay volume – Clay volume

Water volume Water & clay volume – Clay volume 29

Analyze and Interpret

1. What happens to the mass and volume of the modeling clay when it is reshaped? Was your prediction correct?

It remains the same.

2. What property of solids can you infer from this activity?

Solids have a definite volume.

3. You were able to measure the volume of the modeling clay by measuring the water it displaced in a beaker. What property of liquids can you infer by measuring volume in this way?

Liquids have a definite volume.

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Activity 7.2

Temperature and Volume In this activity, you will investigate how temperature affects the volume of air in a balloon.

Materials • 2 balloons

• freezer or ice bath

Procedure 1. Take the balloons and inflate them to an equal size and volume.

2. Place one balloon in the freezer and leave it for 40 minutes. Place the other balloon somewhere in your classroom away from direct sunlight.

3. Remove the balloon from the freezer and place it beside the other balloon. Record your observations.

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Observations Draw and label a diagram of you balloons before and after freezing.

Analyze and Interpret

1. What changes occurred in the frozen balloon compared to the balloon left outside?

The balloons had different volumes.

2. What property of gases can you infer from this activity?

Gases can change in volume.

3. All matter is made up of tiny particles. Describe what happened to the frozen balloon in terms of the particles that make up air.

The atoms/particles in a gas move more slowly when the gas is cooled, which causes the gas to condense.

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Activity 7.3

Temperature and Evaporation Rate As a class, plan and conduct an investigation on the effect of temperature on the evaporation rate of water.

Materials List the materials you will use.

Make a Prediction How will temperature affect the evaporation rate of water?

Procedure Write the steps you will take.

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Observations Use the space below to draw and label a diagram to show how you investigated the effect of temperature on the evaporation rate of water.

Analyze and Interpret

1. How does temperature affect the evaporation rate of water?

Was your prediction correct?

Hotter temperatures cause the water to evaporate faster.

2. Why is it useful to know about the relationship between temperature and evaporation rate?

Knowing the relationship between temperature and evaporation rate can be useful for predicting evaporation in a given environment.

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Activity 7.4

Density of Fresh Water and Salt Water In this activity, you will investigate how adding salt to water changes its density.

Materials • an egg

• beaker

• table salt

• tablespoon

Procedure 1. Work in pairs. Take the egg and gently place it into the beaker. Half fill the beaker with tap water and record your observations.

2. Add tablespoons of salt and stir the solution until the egg floats to the surface of the salt water solution. Record your observations.

3. Place the reverse side of the spoon over the egg and slowly fill the beaker with fresh water from the tap.

Record your observations.

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Observations Draw and label a diagram of your observations at the three stages of the activity.

Stage 1

Stage 2

Stage 3

Analyze and Interpret

1. Describe the position of the egg in the water at each stage.

Explain why the position of the egg changes in relation to density.

2. Describe how the density of water changes when salt is added in terms of the particles that make up matter.

Adding salt to the water makes it less dense causing it to float.

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Activity 7.5

Making Physical Changes to Chocolate In this activity, you will investigate how changing the state and shape of chocolate affects its properties.

Materials • heart-shaped chocolate mold

• wax paper

• seashell-shaped chocolate mold

• mixing bowl

• heart-shaped chocolates

• tablespoon

Procedure 1. Work in pairs. Your teacher will give you some heartshaped chocolates to observe. Place them on the wax paper and make notes of their size and shape.

Record your observations.

2. Your teacher will then place the chocolates in a mixing bowl and heat them until they melt.

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3. Observe the melted chocolate in the mixing bowl. Record your observations.

4. Use the tablespoon to move the melted chocolate into the seashell mold.

5. Your teacher will place the mold in the refrigerator until the chocolate sets.

6. Remove the chocolates from the mold and place them on the wax paper. Make notes of the size and shape of the seashell-shaped chocolates and record your observations.

7. Reverse the change by repeating the steps of melting and re-setting the chocolate back in the heart-shaped mold.

8. Remove the chocolates from the mold and place them on the wax paper. Make notes of the size and shape of the heart-shaped chocolates and record your observations.

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Observations Draw and label a diagram of your observations at each stage of the activity.

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Analyze and Interpret

1. List and describe the changes of state that occurred in this activity.

Heating the chocolate caused it to change from a solid to a liquid.

Cooling the melted chocolate caused in to change from a liquid to a

solid.

2. Were the changes made to the chocolate reversible or irreversible? reversible

3. Were the changes made to the chocolate physical changes or chemical changes? Explain how you know.

The changing state of chocolate caused when it is heated and

cooled is a physical change as no new matter is made.

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Activity 7.6

Apple Oxidation Materials • apple

• 2 paper plates

• marker pen

• lemon wedges

• dish

Procedure 1. Work in pairs. Use the marker to label the paper plates ‘Lemon’ and ‘No lemon’.

2. Squeeze the lemon wedges until the bottom of the dish is covered with lemon juice.

3. Your teacher will cut the apple in half. Place one half of the apple on the paper plate labeled ‘No lemon’.

4. Place the other half of the apple into the dish of lemon juice so that the pulp is submerged in the juice.

Leave it to soak for one minute.

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5. Remove the apple half from the dish and place it on the paper plate labeled ‘Lemon’.

6. Record your observations of the apple halves every 20 minutes for one hour.

Observations Draw and label a diagram of your observations at each stage of the activity.

lemon

no lemon

lemon

no lemon

20 min

40 min

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lemon

no lemon

60 min

Analyze and Interpret 1. Some substances can affect the rate of chemical changes.

Describe what effect the lemon juice had on the rate of browning of the apple.

2. How could slowing down or speeding up chemical changes be helpful to people? Provide an example.

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Activity 7.7

Chemical Change As a class, plan and conduct an investigation to show that the new matter formed in a chemical change has properties different from the original matter.

Materials List the materials you will use.

Make a Prediction Predict what properties will change after the chemical change has occurred.

Procedure Write the steps you will take.

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Observations 1. List and describe the properties of matter that changed as a result of the chemical change.

Property

Before

After

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2. Complete the table to identify changes that occurred in the chemical change.

Change in color?

Odor produced?

New solids formed?

Change in temperature?

Formation of bubbles?

Analyze and Interpret

1. Are chemical changes reversible or irreversible? Explain.

Chemical changes are irreversible because they are the result of

chemical reactions whereby new matter is made.

2. How is understanding that properties of matter change when a chemical change occurs useful to people?

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Activity 7.8

Mixtures and Solutions – Comprehension 1. Use your textbook to help you fill in the blanks. (a) Mixtures can be classified into two broad groups –

heterogeneous

and

homogeneous

mixtures. A

heterogeneous salad is a mixture. It contains different amounts of fruits and vegetables. suspension

(b) Cooking oil mixed with water is a . If allowed

settle to for a few seconds, the oil will float on top of the water. (c)

A mixture of soil and water will settle in about

an hour

sink

humus

(d)

Solutions

. Sand and rock particles will and the organic matter that makes up the will float. can be in gases, liquids and solids.

Air

is a solution. It is a mixture of nitrogen, oxygen, carbon dioxide and other gases. (e) People often mix different kinds of

metals

together

substances or with other to produce a new metal with specific properties. They may be made to be lighter or stronger.

These mixtures of metals are a type of solution called

alloys

.

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Aluminum (f) alloys contain mostly aluminum along with other metals, such as steel. They are often used when an object lightweight Stainless

needs to be .

steel is a metal solution made of iron and other metals to make it more

resistant

to the chemical change of rusting.

(g)

Gold

is often used to make jewelry.

Pure

gold is soft and is often mixed with other

metals to make it

stronger

and more durable.

2. Use the Venn diagram to compare and contrast heterogeneous and homogeneous mixtures.

Heterogeneous mixtures

not completely/ evenly mixed

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Homogeneous mixtures

mixtures matter

completely/evenly mixed

Engineer It!

Sugar Cleanup Challenge A truck had a minor accident and spilled a container full of sugar onto a sandy beach. Your challenge is to separate the sugar from the sand. In small groups, design and test a process of recovering the sugar from the sand.

Draw a Model Draw a labeled diagram of your separation process.

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Materials List the materials you will use to build and test your separation process.

Procedure Write the steps you will take.

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Observations Draw and label a diagram of your separation process in action.

Analyze and Interpret 1. Evaluate the effectiveness of your separation process. How did it compare with the processes designed by other groups?

2. How could your group’s design be improved?

3. Name a problem that can be solved using a separation process.

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Activity 7.9

Matter Crossword Read the clues relating to matter and complete the crossword on the opposite page.

Across 4. Many physical changes, including those that involve a change in state, are .

6 Boiling water is an example of this kind of change.

7. Burning paper is an example of this kind of change.

9. The process of changing from a liquid to a gas.

10. The process of changing from a solid to a liquid.

12. This state of matter takes the shape of its container.

Down 1. The process of changing from a gas to a liquid.

2. The process of changing from a liquid to a solid.

3. This state of matter takes the shape of its container and is compressible.

5. The name given to a mixture that will separate if left to settle.

8. The name given to a mixture in which the substances mix completely and are evenly distributed.

11. Ice is in this state of matter.

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Review

Matter 1. Label the states of matter. Draw to show the arrangement of particles in each state.

solid

liquid

gas

2. How do the particles in solid ice change when it begins to melt?

At what temperature does this begin to occur?

When solid ice begins to melt, the particles in the ice begin to separate and move faster. This begins to occur at 0oC.

3. How do the particles in water change when it boils?

At what temperature does this begin to occur?

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When water boils, the particles break apart. This begins to occur at 100oC.

4. Label the processes that take place as matter changes state. freezing

condensation

melting

evaporation

5. Provide two examples of physical change.

Accept a range of reasonable answers (e.g. cutting paper, freezing water).

6. Provide two examples of chemical change.

Accept a range of reasonable answers (e.g. cooking, burning, rusting).

7. What does it mean if a change made to matter is irreversible?

A irreversible change can never be changed back to its original form.

8. Use the Venn diagram to compare and contrast mixtures.

Homogeneous mixture not completely/ evenly mixed

Heterogeneous mixture mixtures matter

completely/evenly mixed

9. How does distillation separate a solution of salt and water?

The mixture of salt and water is heated until the water boils, turning into

steam. The steam is then collected in a condenser to turn back into water.

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Activity 8.1

Forces and Motion 1. What is a force?

A force is a push or a pull.

2. What must occur for an object to be set in motion?

Unbalanced force(s) must be applied to the object.

3. How does the magnitude of a force acting on an object affect its motion?

The greater the magnitude of the force, the greater the change in

motion/the faster or further the object moves.

4. How does the direction in which a force is applied to an object affect its motion?

The motion of the object will be in the same direction as the force

applied to it.

5. How does an object’s mass affect the magnitude of the force required to set it in motion?

The greater the mass of an object, the greater the magnitude of the

force required to set it in motion.

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Activity 8.2

Magnitude and Direction of Forces Plan and conduct an investigation to provide evidence that the change in an object’s motion depends on the magnitude and direction of the forces acting upon it along with the object’s mass.

Materials List the materials you will use.

Procedure Write the steps you will take to provide evidence of how a change in motion depends on the: Magnitude of force

Direction of force

Mass of object

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Observations Draw simple labeled diagrams to show how you demonstrated the factors affecting an object’s change in motion. Use arrows to show the direction and magnitude of the applied forces.

Magnitude of force:

Direction of force:

Mass of an object:

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Analyze and Interpret 1. What evidence did you provide to demonstrate that an object’s motion depends on the magnitude of the forces applied to it?

2. What evidence did you provide to demonstrate that an object’s motion depends on the direction of the forces applied to it?

3. What evidence did you provide to demonstrate that an object’s motion depends on its mass?

4. A bowling ball and a basketball are at rest on the ground. Describe the motion of each ball if a force of the same magnitude and direction is applied to each ball. Explain your answer.

The basketball will move further/faster as it has less mass.

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Activity 8.3

Balanced and Unbalanced Forces 1. What does it mean when the forces acting on an object are balanced?

When the forces acting on an object are balanced, the net force is zero

and there is no change in motion.

2. What occurs when the forces acting on an object are unbalanced?

When the forces acting on an object are unbalanced, the net force is not zero and there is a change in motion.

3. Describe the forces acting on the computer mouse.

Are the forces balanced or unbalanced? (a) A computer mouse at rest on a desk.

Gravity is pull the mouse down. The table is pushing the mouse up.

The net force sums to zero.

Balanced 3 Unbalanced

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(b) A computer mouse is pushed and pulled.

Applied forces from the hand move the mouse. The net forces do not sum to zero.

Balanced (c)

Unbalanced 3

A computer mouse on a desk is pushed down from above.

Applied force from the hand and gravity is pull the mouse down.

The table is pushing the mouse up. The net force sums to zero.

Balanced 3 Unbalanced 61

4. Label and add arrows to show the magnitude and direction of forces acting on each object. Are the forces balanced or unbalanced? (a) A mango falls from a tree.

Balanced

Unbalanced 3

(b) A skydiver falls safely to the surface of the Earth.

Balanced (c)

Unbalanced 3

A weightlifter holds a barbell with weights above his head.

Balanced 3 Unbalanced 62

5. Check if the forces are balanced or unbalanced. Describe the motion of the object or state if the object is at rest. (a)

Motion: The girl moves in a back and forth motion.

Balanced

Unbalanced 3

(b)

Motion: The balls move up and down in a circular motion.

Balanced

Unbalanced 3

(c)

Motion: The girl balances on the rope and is not in motion.

Balanced 3 Unbalanced 63

Activity 8.4

Applied Force In each photograph, describe the contact forces acting on the objects and the resulting motion.

(a)

Applied forces The puck is pushed and pulled.

Motion The puck moves in the direction of the applied forces applied to it.

(b)

Applied forces The boy pushes the scooter.

Motion The boy moves in a straight line.

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(c)

Applied forces The player is applying a push force to the ball.

Motion The ball will move up into the air.

(d)

Applied forces The finger is applying a push force to a domino.

Motion The dominoes fall over as they knock into each other.

(e)

Applied forces The children apply push forces against the force of gravity.

Motion The children move in an up and down motion.

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Activity 8.5

Friction – Comprehension 1. Use your textbook to help you fill in the blanks. opposes

(a) Friction is a force that when the

surfaces

motion. It occurs

of objects rub together.

(b) The force of friction between two objects is dependent on how hard the objects are

roughness

(c)

pushing/pressing

together and the

of their surfaces.

Rough

surfaces produce more friction than

smooth

surfaces.

2. Provide an example of an object that maximizes friction.

Accept a range of reasonable answers (e.g. car tires, shoe soles).

3. Provide an example of an object that minimizes friction.

Accept a range of reasonable answers (e.g. slides, skis.

4. Identify the parts of a bicycle that aim to maximize friction and the parts that aim to minimize friction.

The parts of a bicycle that aim to maximize friction are the tires and

brakes. The part of the bike that aims to minimize friction is the seat

and frame.

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Activity 8.6

Magnetic and Electric Forces 1. Draw field lines and arrows to show how the poles of magnets interact with each other. (a)

(b)

2. Draw plus signs ( + ) and minus signs ( – ) on the balls to show their charge and demonstrate the forces acting between them (a) Opposite charges attract. (b)

+

-

Like charges repel.

+

+ 67

Activity 8.7

Gravity 1. Gravity is a non-contact force. What does this mean?

Provide an example.

This means gravity can act at a distance. When you throw a ball into the air, the Earth’s gravity pulls it down without being in contact with it.

2. Apart from mass, what other factor determines the strength of gravitational force? Provide an example.

The distance between objects. The closer an object it to Earth, the greater the magnitude of the Earth’s gravitational force acting upon it.

3. Gravity and electric force are non-contact forces. List two ways they are similar and two ways they are different. act at a distance can attract objects

gravity cannot repel electric force can be generated

4. The force of gravity between two objects is always attractive. What prevents the Earth and its moon from colliding together due to their mutual attraction?

The moon’s orbit around the Earth prevents the Earth and its moon from colliding.

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Activity 8.8

Newton’s Laws of Motion Materials • playing card

• string

• scissors

• cup

• coin

Procedure 1. Use the scissors to put a hole in the playing card and attach a piece of string as shown.

2. Place the playing card on top of the cup. Place the coin on the center of the playing card.

3. Hold the end of the string and gently pull the card. Observe the motion of the coin.

4. Repeat Step 2 but now pull the card away quickly. Observe the motion of the coin.

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Observations 1. Describe the motion of the coin in Step 3.

2. Describe the motion of the coin in Step 4.

Analyze and Interpret

1. Use your knowledge of inertia and Newton’s first law of motion to explain the motion of the coin in Step 3.

The coin remained on the card due to inertia – the resistance to change in motion.

2. Use your knowledge of inertia and Newton’s first law of motion to explain the motion of the coin in Step 4.

The coin opposed the motion of the card and fell into the cup.

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Engineer It!

Crash Test Egg Challenge In the unfortunate event of a car collision, the forces that act on the human body can cause serious injury or death. For this reason, car manufacturers implement a number of design features to reduce the impact of forces on the car’s occupants during a collision. To test the effectiveness of their designs, the cars undergo collision tests in a controlled environment. Crash test dummies model the human body during these collisions. Scientists and engineers collect data from the crash test dummies to determine how effective the design features are at preventing injury.

Now it’s your turn. In small groups, design and build a model car that will protect a hard-boiled egg from breaking during a collision. Use your knowledge of Newton’s laws of motion to guide the design of your safety features.

Materials List the materials you will use to build your model car.

Please keep me safe!

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Draw a Model Draw a labeled diagram of your design.

Observations Record your observations from the model car crash tests.

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Analyze and Interpret 1. List and describe the features of your model car that were designed to protect the hard-boiled egg during a collision

2. How effective was your design at protecting the egg?

3. Compare your design to that of other groups. Which group had the most effective design?

4. In what ways could your design be improved?

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Review

Forces 1. Why is more force required to raise an object of greater mass?

The force required to raise an object of greater mass is greater because the force of gravity acting on the object is greater.

2. What can you infer about the forces acting on an object if there is no change in motion?

The forces are balanced.

3. Provide three examples of applied forces used in a game of soccer.

Answers may vary e.g. kick, catch, throw etc.).

4. How does the weight of an object affect the friction between the object and the object it is in contact with?

In general, the greater the weight of an object, the more friction it will experience with the object it is in contact with.

5. How does the roughness of the surface of an object affect the friction between the object and the object it is in contact with?

The rougher the surface of an object, the greater the friction between it

and the object it is in contact with.

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6. Describe the forces between two magnets when: (a) like poles are brought together.

The magnets repel each other.

(b) opposite poles are brought together.

The magnets attract each other.

7. What causes an electric force within an object?

The electric force is caused by the imbalance of charges in an object.

8. What interaction will occur when two negatively charged objects are brought together?

They will repel each other.

9. How does an object’s mass and distance from another object affect the gravitational force between them?

The greater an object’s mass and the closer the two objects are to each other, the stronger the gravitational force between them.

10. Use Newton’s first law of motion to describe the inertia of a fighter pilot as he takes off and lands.

When taking off, the fighter pilot will resist a change in motion and

will be pushed backwards. When landing, the fighter pilot will resist a change in motion and will be pushed forward.

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Activity 9.1

Factors Affecting Work Materials • block of wood

• Newton meter

• string

• scissors

• measuring tape

• tape

Make a Prediction Which will result in more work being done – dragging a weight a distance of one meter on a smooth surface or dragging a weight a distance of one meter on a rough surface? Explain your answer.

Procedure 1. Tie the string around the wooden block and attach the hook of the Newton meter to the string.

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2. Hold the handle of the Newton meter and drag it at a constant rate for a distance of 1 m. Observe and write down the average force applied as indicated on the Newton meter.

3. Repeat Steps 1 and 2 on a rough surface.

Observations Record your observations in the table below.

Surface

Distance (m)

Force (N)

Work (J)

smooth rough

Analyze and Interpret 1. Was your prediction correct? On which surface was more work done?

More work was done on the rough surface.

2. Why was the amount of work done different on different surfaces?

Due to the force of friction opposing the motion of the block of wood.

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Activity 9.2

Work – Comprehension 1. Use your textbook to help you fill in the blanks. (a) Work is defined as an object a certain

force distance

moving . effort

(b) Work has been done when a force, called the is applied to an object, called the moves a given distance. (c)

The amount of work done relates to the

the force and the

distance

(d) An object with greater to move the same distance.

mass

load

and it

magnitude moved.

requires more force

2. How is work calculated and measured?

To calculate work, we multiply the magnitude of the force by the

distance the object moved. work = force x distance

3. Sophie used a force of 100 N to drag a box a distance of 20 meters.

How much work was done? Show your working.

100 N × 20 m = 2000 J

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of

4. Ethan is stretching his legs by pushing against a brick wall.

Is work being done? Explain your answer.

No work is being done because the

brick wall is not moving.

5. A ripe apple drops from a branch and falls to the ground.

Has work been done? Explain your answer.

Work is being done as the force

of gravity pulls the apple from the branch to the ground.

6. Halle uses a rope to lift a box of clothes into her tree house.

Has work been done? Explain your answer.

Work is being done as Halle uses pulls to raise the box of clothes a distance.

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Activity 9.3

Simple Machines 1. What is a simple machine?

Simple machines are devices, usually with one moving part, that make work easier.

2. Label the simple machines. Use arrows to show the direction of the effort and the force applied to the load. (a)

(b)

inclined plane (d)

(c)

pulley (e)

wheel and axle

gears (f)

lever

wedge

3. List the three ways simple machines can function to make work easier.

• Multiplying the applied force by increasing the distance of the effort.

• Multiplying speed.

• Changing the direction of the applied force.

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4. Name the simple machine shown in each picture. (a)

(b)

inclined plane (c)

wheel and axle (d)

wheel and axle (e)

pulley (f)

inclined plane (g)

lever (h)

wedge

gears

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Activity 9.4

Inclined Planes 1. Riley is moving house. Draw an inclined plane in the picture below to make it easier for her to load her drawers into the moving truck.

2. If Riley uses an inclined plane to load her drawers, will the amount of work done change compared to lifting the drawers into the truck?

Explain your answer.

If Riley uses an inclined plane to load her drawers, the amount of work done will not change. A smaller force will be required, but the distance moved will be greater.

3. How does an inclined plane make work easier?

An inclined plane can make work easier by reducing the effort

required, but increasing the distance the load moves.

4. List three objects that make use of an inclined plane.

Accept a range of reasonable responses (e.g. ramps, stairs, skate ramp etc.).

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Activity 9.5

Does an Inclined Plane Make Work Easier?

Plan and conduct an investigation to provide evidence to support the claim that an inclined plane makes work easier.

Suggested Materials • books

• wooden boards of different lengths

• toy car

• Newton meter or elastic band

• string

Procedure Write the steps you will take.

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Observations Draw a labeled model to show how you used inclined planes.

Create a table to record your observations.

Analyze and Interpret

1. What evidence did you observe that supported the claim that an inclined plane makes work easier?

Less effort was required to move the load.

2. How does an inclined plane affect the effort required to move an object?

An inclined plane reduces the effort required to move an object.

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Activity 9.6

Types of Levers 1. Label the parts of a lever.

Draw arrows to show the direction movement. (a)

effort load

fulcrum

(b) effort

load fulcrum 2. What is the fulcrum?

The fixed point in a lever.

3. How do the levers above make it easier to raise the load?

An inclined plane can make work easier by reducing the effort

required, but increasing the distance over which the effort moves.

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4. Circle the lever that requires less effort to move the rock.

What did Riley do to make work easier?

Riley decreased the distance between the fulcrum and load.

5. Circle the lever that requires less effort to move the rock.

What did Ethan do to make work easier?

Ethan increased the distance of the effort.

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6.

I dentify each type of lever. Explain how each lever functions to make work easier.

(a)

Type of lever: third-class lever How it functions: Greater effort is required to move the load, but the speed at which the load moves is multiplied.

(b)

Type of lever: second-class lever How it functions: The effort moves over a larger distance to raise the load a smaller distance but with greater force.

(c)

Type of lever: first-class lever How it functions: A first-class lever changes the direction of the effort.

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Activity 9.7

Investigating Levers In this investigation, you will make a first-class lever to demonstrate how changing the position of the fulcrum, effort and load changes the amount of effort required to raise an object.

Materials • 3 pencils

• 2 identical plastic cups

• wooden ruler (40-50 cm in length)

• tape

• marbles of the same size

Make a Prediction Circle the lever which requires the least amount of effort to raise the load.

1.

Lever A

Lever B

Lever C

Lever D

Lever E

Lever F

2.

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Procedure 1. Take three pencils of the same size and secure them into a pyramid shape using the tape as shown.

2. Use the tape to attach a plastic cup to each end of the ruler. Place the pencils under the ruler to act as the fulcrum of a first-class lever.

3. Place three marbles in the plastic cup on the left side of the lever.

4. Position the fulcrum to represent Lever A on the previous page. Add marbles one at a time to the cup on the right side of the lever. Record the number of marbles required to raise the load.

5. Repeat Steps 3 and 4, but change the position of the fulcrum to represent Levers B and C. 6. Repeat Steps 3 and 4, but change the position of the cup on the right side to represent Levers D, E and F.

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Observations 1. Record your observations in the table below.

Lever

Marbles Needed to Raise Load

A B C D E F 2. Draw a simple labeled diagram to show the position of the fulcrum that resulted in the least amount of effort required to raise the load.

3. Draw a simple labeled diagram to show the position of the effort that resulted in the least amount of effort required to raise the load.

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Analyze and Interpret 1. Was your prediction correct? Which two levers required the least amount of effort to raise the load?

2. Based on your observations, how does the location of the fulcrum affect the effort required to raise a load?

3. Based on your observations, how does the distance between the fulcrum and effort affect the effort required to raise a load?

4. Riley wants to move the rock into the hole. Draw a diagram of a labeled lever that will allow her to move the rock with the least amount of effort. Use an arrow to show where she should apply the effort.

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Activity 9.8

Investigating Pulleys Materials • 2 pulleys

• Newton meter

• string

• 250-gram weight

• retort stand with clamp and bar

Make a Prediction How will adding a movable pulley to a fixed pulley change the amount of effort required to raise a load?

Procedure 1. Use a piece of string to attach one pulley to the retort stand. Take another piece of string and tie one end to the 250-gram weight.

2. Pass the free end of the string through the pulley. Attach the Newton meter to the string as shown on the next page.

3. Gently pull on the Newton meter at a constant, steady rate. Observe and record the amount of force required to raise the weight.

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4. Untie the weight and attach a movable pulley to the retort stand to create the pulley system shown below.

5. Repeat Step 3.

Observations Record the force required to raise the load.

Type of Pulley

Force Needed to Raise Load (N)

Fixed Pulley Pulley System

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Analyze and Interpret

1. Was your prediction correct? How did adding a movable pulley to a fixed pulley change the amount of effort required to raise the load?

2. How did the fixed pulley function to make work easier when raising the load?

It increased the distance over which the effort moved.

3. How did the pulley system function to make work easier when raising the load?

It increased the distance and changed the direction of the effort allow

the effort to be applied in the same direction as gravity.

4. Did the amount of work done change when raising the load using the pulley system compared to raising the load using the fixed pulley?

Explain your answer.

The amount of work done was unchanged, but the amount of

applied force required decreases as it is applied in the same direction

as gravity.

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Activity 9.9

Investigating a Wheel and Axle Materials • string

• bucket

• 2 cardboard tubes

• tape

• 500-gram weight

• 30 cm ruler

• broom handle

• scissors

Procedure 1. Use the tape to attach the cardboard tubes to your desk as shown.

Slide the broom handle through the tubes.

2. Cut a 1 m length of string and tie it to the bucket handle. Tie the other end of the string to the broom handle and secure it with tape.

3. Place the 500-gram weight in the bucket. Turn the broom handle to raise the bucket. Take note of the amount of effort required.

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4. Use the tape to firmly attach the ruler to the broom handle as shown.

5. Repeat Step 3, this time turning the ruler to raise the load.

Observations escribe the effort required to raise the load when turning the broom D handle and when turning the ruler.

Analyze and Interpret

1. In the illustration above, label the wheel, axle and load. Draw an arrow to show how the effort was applied.

2. How does a wheel and axle function to make work easier?

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The effort applied to the wheel results in less effort required to turn the axle as the effort to turn the wheel is applied over a greater distance.

Activity 9.10

Investigating Gears Use the diagram of the gears below to answer the questions.

Gear A Gear B 1. In what direction will Gear B rotate if Gear A is rotated in a clockwise direction? anti-clockwise

2. Halle attaches a third gear to Gear B. In what direction will Gears A and B rotate if Halle rotates her gear in an anti-clockwise direction?

Gear B will move in a clockwise direction.

Gear A will move in an anti-clockwise direction.

3. If Gear B turns one complete rotation, will Gear A turn more or less than one rotation? Explain your answer.

Gear A will turn more than one rotation as it is smaller.

4. List two ways gears can function to make work easier.

They can multiply the applied force when the effort applied to a larger gear moves over a greater distance than a connected smaller gear. They

can also multiply speed when a smaller gear turns a larger gear.

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Activity 9.11

Investigating Wedges 1. What is a wedge?

A wedge is a simple machine that is triangular in shape, much like two inclined planes joined back-to-back.

2. Provide three examples of objects that make use of wedges.

Accept a range of reasonable answers (e.g. axes, door stops, screwdriver).

3. How does a wedge function to make work easier?

A wedge makes work easier by changing the direction of the applied force.

4. Draw a simple labeled diagram to show how an axe can be used to split a log. Use arrows to show the direction of forces.

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Activity 9.12

Compound Machines 1. What are compound machines?

An object that consists of two or more simple machines.

2. Identify and label the simple machines that make up each compound machine. (a)

wheel and axle lever

(b)

lever

wheel and axle 99

(c) lever

wedge

(d) wedge lever

(e) wheel and axle gears

wheel and axle 100

Engineer It!

Design and Build a Compound Machine As a class, identify and define a problem that can be solved through the design and development of a new or improved compound machine. In small groups, design and build a solution to the defined problem. Test the effectiveness of your design then identify its strengths and weaknesses by comparing your solution with the solutions of other groups.

Problem Describe the problem that can be solved by the development of a new or improved compound machine.

Solution Describe how your group’s compound machine will solve the problem.

Materials List the materials your group will use to build the compound machine.

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Draw a Model Draw a labeled model of your design.

Analyze and Interpret

1. How did you evaluate the effectiveness of your design?

2. Compare your solution with those of other groups. List the strengths and weaknesses of your solution.

3. How could your group’s solution be improved?

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Review

Work and Simple Machines 1. What is work?

Work is defined as force moving an object a certain distance.

2. How is work calculated?

work = force x distance

3. A ball rolls down an inclined plane. Has work been done?

Explain your answer.

Yes, work has been done as the force of gravity moved the ball a distance.

4. Provide an example whereby a simple machine makes work easier by increasing the distance over which the effort is applied.

Accept a range of reasonable responses.

5. Provide an example whereby a simple machine makes work easier by changing the direction of the effort.

Accept a range of reasonable responses.

6. Provide an example of an object that makes use of gears.

Accept a range of reasonable responses (e.g. a bicycle).

7. List one compound machine and the simple machines it is made of.

Accept a range of reasonable responses.

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Activity 10.1

What Is Electricity?

1. Use your textbook to help you fill in the blanks. atoms

(a) All matter is made up of tiny particles called

(b) An atom is made up of much smaller particles called

protons

and

(c) Protons have a

positive

negative

charge.

electrons

.

charge and electrons have a

(d) When an atom loses an electron, it becomes

positively

charged. When an atom gains an electron, it becomes

negatively

charged.

(e) The energy associated with the exchanges and movement of charge is called

electricity

.

2. Why is electricity so useful to people?

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As it can be readily/easily changed into different forms of energy.

.

Activity 10.2

Aluminum Can Race!

Materials • cloth

• balloon

• aluminum can

• measuring tape

• tape

• stopwatch

Procedure 1. Use the tape and measuring tape to mark a start and finish line 3 m apart on the classroom floor.

2. Inflate the balloon and rub it with a cloth back and forth 10 times.

3. Place the empty aluminum can on the start line. Start the stopwatch and hold the balloon near the aluminum can without touching it.

4. Pull the can to the finish line without the balloon and can touching.

Record your race time.

5. Increase the number of times the balloon is rubbed on the cloth and repeat Steps 3 and 4 two more times.

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Observations Record your observations in the table.

Trial

Number of Rubs

1

10

Race Time (s)

2 3

Analyze and Interpret

1. Describe what occurred when the balloon was rubbed on the cloth.

2. What caused the aluminum can to be attracted to the balloon?

As it can be readily/easily changed into different forms of energy.

3. What effect did increasing the number of times the balloon was rubbed on the cloth have?

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Activity 10.3

Electric Charge – Comprehension 1. Use your textbook to help you fill in the blanks. (a) When an object loses electrons is becomes

positively

charged.

(b) When an object gains electrons is becomes

negatively

(c) Unlike charges Like charges

charged. attract repel

each other. each other.

(d) The movement of the buildup of electric charge from one place to another is called

electric discharge

.

2. Use the words ‘electric charge’ and ‘electric discharge’ to explain what occurs during a lightning strike.

During a lightning strike, there is a difference in electric charge between the clouds and the ground. Electric discharge occurs when the negative charges race towards the ground. We see this as a bolt of lightning.

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Activity 10.4

Electrical Conductors and Insulators In this investigation, you will plan and conduct an investigation that uses a simple circuit to determine if various classroom objects are electrical conductors or electrical insulators.

Make a Prediction List the objects you will be testing in the table on the next page.

Predict if they are electrical conductors or electrical insulators.

Materials List the materials your group will use to build a simple electric circuit.

Procedure Write the steps you will take.

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Draw a Model Draw a labeled model to show how you tested the electrical conductivity of the objects.

Observations Record your observations in the table.

Object

Prediction

Observation

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Analyze and Interpret

1. How were you able to determine if an object was an electrical conductor or an electrical insulator?

2. What do the objects that are electrical conductors have in common?

3. How is knowing about the electrical conductivity of objects and materials useful?

1 10

Accept a range of reasonable answers (e.g. for safety, for lights and appliances).

Activity 10.5

Using and Conserving Electricity 1. List three ways you use electricity at home and the energy conversions that take place. (a)

Accept a range of reasonable answers.

(b)

(c)

2. List three ways you can conserve electricity at home. (a)

Accept a range of reasonable answers.

(b)

(c)

3. List two advantages of conserving electricity.

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Activity 10.6

Build a Simple Electric Circuit Materials • battery

• battery holder

• insulated wires (with alligator clips)

• bulb

• bulb holder

• switch

Procedure 1. Assemble the circuit components to make a simple circuit.

2. Observe the bulb as you open and close the switch.

3. Observe the bulb as you remove and replace the battery.

4. Observe the bulb as you disconnect, then reconnect a wire attached to the bulb holder.

1 12

Observations Draw a labeled diagram of the circuit you constructed.

Analyze and Interpret 1. Describe what occurred when you opened and closed the switch.

Why did this occur?

2. Describe what occurred when you removed and replaced the battery.

Why did this occur?

3. Describe what occurred when you disconnected and reconnected the wire. Why did this occur?

1 13

Activity 10.7

Connecting Bulbs in Series Materials • battery

• battery holder

• insulated wires (with alligator clips)

• 3 bulbs

• 3 bulb holders

• switch

Make a Prediction How does adding bulbs in series affect the brightness of the bulbs?

Procedure 1. Assemble the circuit components to make a simple circuit consisting of one battery, one bulb and a switch as shown.

1 14

2. Close the switch. Turn off the classroom lights and observe the brightness of the bulb.

3. Add a bulb in series to the circuit as shown.

4. Repeat Step 2.

5. Add a third bulb in series to the circuit as shown.

6. Repeat Step 2.

Observations Order the circuits in terms of the brightness of the bulbs from the least bright (1) to the brightest (3).

3

2

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Analyze and Interpret

1. Was your prediction correct? Based on your observations, how does adding bulbs in series affect the brightness of the bulbs?

2. Wyatt assembled a simple circuit with one battery, one buzzer and a switch. (a) Wyatt adds a bulb in series to the buzzer.

How will this affect the buzzer? Explain your answer.

The buzzer will not be as loud as the electric current will be

shared between the buzzer and bulb.

(b) Wyatt removes the light bulb from the light bulb holder.

How will this affect the buzzer?

The buzzer will not work as the circuit is open and there is not a

complete path along which electricity can flow.

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Activity 10.8

Connecting Batteries in Series Materials • 3 batteries

• 3 battery holders

• 3 bulbs

• 3 bulb holders

• insulated wires (with alligator clips)

• switch

Make a Prediction How does adding batteries in series affect the brightness of the bulbs?

Adding batteries in series will increase the brightness of the bulbs.

Procedure 1. Assemble the circuit components to make a simple circuit consisting of one battery, one bulb and a switch as shown.

2. Close the switch. Turn off the classroom lights and observe the brightness of the bulb.

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3. Add a battery in series to the circuit as shown.

4. Repeat Step 2.

5. Add a third battery in series to the circuit as shown.

6. Repeat Step 2.

Observations Order the circuits in terms of the brightness of the bulbs from the least bright (1) to the brightest (3).

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Analyze and Interpret 1. Was your prediction correct? Based on your observations, how does adding batteries in series affect the brightness of the bulbs?

2. Riley assembled a simple circuit consisting of one battery, one motor and a switch. (a) Riley adds another battery in series.

How will this affect the motor? Explain your answer.

The motor will turn faster as adding batteries in series increases

the electric current.

(b) Riley connected two batteries in series and a bulb in series to the motor. When she closed the switch, none of the output devices worked. Provide two possible reasons why this occurred.

Accept and range of responses (e.g. one device is broken, there is

a break in the circuit the batteries are flat).

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Activity 10.9

Connecting Bulbs in Parallel In small groups, plan and conduct an investigation to demonstrate: • the effect of adding bulbs in parallel on the brightness of the bulbs.

• the effect on bulbs arranged in parallel when one bulb is removed.

Make a Prediction 1. How will arranging bulbs in parallel affect the brightness of the bulbs?

Two bulbs arranged in parallel will glow brighter than if they were

arranged in series.

2. How will removing a bulb arranged in parallel affect the other bulbs in the circuit?

The remaining bulbs will continue to light up.

Materials List the materials you will use.

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Procedure Write the steps you will take.

Observations Record your observations in the space below.

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Analyze and Interpret

1. Were your predictions correct? (a) Based on your observations, how does adding bulbs in parallel affect the brightness of the bulbs?

Bulbs arranged in parallel will glow brighter than if they were arranged in series.

(b) Based on your observations, how does removing a bulb arranged in parallel affect the other bulbs in the circuit?

The remaining bulbs will continue to light up.

2. Why are lights and sockets commonly arranged in parallel in homes and buildings?

So that the devices and appliances in the circuit will continue to operate when one device breaks.

3. Write the steps you could take to find out the effect on the life of batteries when the batteries are arranged in parallel.

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Activity 10.10

Circuit Symbols and Diagrams 1. Complete the table.

Circuit Component

Name

Circuit Symbol

wire

bulb

battery

two batteries

motor

buzzer

switch

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2. Match the circuits to their circuit diagrams.

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Activity 10.11

Drawing Circuit Diagrams 1. Draw a circuit diagram for each circuit. (a)

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(b)

126

(c)

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(d)

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(e)

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2. Using all of the circuit components below and as much wire as needed, draw a circuit diagram that will result in the bulbs glowing the brightest.

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Activity 10.12

Electromagnets – Comprehension 1. Use your textbook to help you fill in the blanks. (a) When

electric current

magnetic field

flows through a wire, it produces a

.

electromagnet (b) An is a magnet that attracts magnetic materials when electric current flows through it. (c) Electromagnets are particularly useful as the magnetic property can be easily switched on and off by flow of the

electric current

controlling

the

.

2. Describe three ways you can increase the strength of an electromagnet. (a)

Increase the number of coils of wire.

(b)

Coiling the wire around a magnetic material increases the strength

of the electromagnet.

(c)

Adding more batteries in series.

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Activity 10.13

Strength of Electromagnets Materials • 2 batteries

• 2 battery holders

• insulated wires

Procedure 1. Tightly wrap the insulated wire around the iron nail 20 times. Leave about 20 cm of wire at each end of the nail.

2. Create an electromagnet by attaching each end of the wire to a battery holder containing one battery.

3. Hold the electromagnet near a pile of staples. Count and record the number of staples attracted to the electromagnet.

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• tape

• iron nail

• staples

4. Disconnect the wires from the battery holder and attach each wire to a battery holder containing two batteries.

5. Repeat Step 3.

6 Repeat Steps 1 to 3, this time wrapping the wire 50 times around the iron nail.

Observations Record your observations in the table.

Batteries

Coils of Wire

Staples Attracted

Analyze and Interpret 1. How does increasing the number of batteries affect the strength of an electromagnet?

Increasing the number of batteries increases the strength of the

electromagnet.

2. How does increasing the number of wire coils affect the strength of an electromagnet?

Increasing the number of wire coils increases the strength of the

electromagnet.

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Engineer It!

Electromagnet Challenge You have learned about the different ways we can increase the strength of an electromagnet. Now it’s your turn. In small groups, put your knowledge and skills to the test by using the materials given to you by your teacher to design and build the strongest electromagnet you can. Challenge other groups to see how many paper clips your electromagnet can attract.

Materials List the materials given to you by your teacher.

Procedure Write the steps you will take.

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Draw a Model Draw a labeled model of your group’s electromagnet.

Analyze and Interpret 1. How many paper clips was your electromagnet able to attract?

2. Compare your group’s electromagnet with that of other groups.

List the strengths and weaknesses of your design.

3. How could you increase the strength of your group’s electromagnet?

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Review

Electricity and Circuits 1. What is electricity?

The energy associated with these exchanges and movement of

charge.

2. How is electric current different from electric discharge?

The flow of electric current is steady and continuous, while the flow of

electric discharge is intermittent.

3. What energy conversions take place when an electric heater is switched on?

Electrical energy is converted into heat and light.

4. In the space below, draw a circuit diagram with two buzzers in series, a battery and a switch.

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5. How does adding bulbs in series affect their brightness?

Adding bulbs in series decreases the brightness of the bulbs.

6. How does adding bulbs in parallel affect their brightness?

When bulbs are arrange in parallel, the brightness of the bulbs

remains the same.

7. Sophie made an electromagnet by coiling a wire 10 times and attaching each end of the wire to a battery. List three things Sophie can do to increase the strength of the electromagnet.

(a)

Increase the number of coils of wire.

(b) Coiling the wire around a magnetic material increases the strength of the electromagnet. (c)

Adding more batteries in series.

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This publication would not have been possible without the tireless effort of our production team.

Special thanks to: Matthew Cole, Daniel Cole, Wang Hui Guan Joseph Anderson, Halle Taylor-Pritchard, Sophie Taylor-Pritchard, Tejal Thakur Natchanuch Nakapat, Varasinun Mathanattapat, Kanungnit Pookwanmuang, Saijit Lueangsrisuk Original Illustrations: Natchanuch Nakapat, GraphicsRF, Blue Ring Media and Interact Images Royalty-free images: Shutterstock, Adobe Stock