RiAus PDplus low level speeding notes - Years 10-11

The science and myths of low level speeding

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years 10-11

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Introduction to the guide

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About the guide

Created by Sally Parker Editor Heather Catchpole Designer Fiona MacDonald Editor-in-Chief Wilson da Silva Publisher Kylie Ahern

RiAus PDplus Teacher Notes is a new initiative of RiAus that has been designed to assist middle school (Years 7 – 9) teachers engage and involve their students.

The notes supplement a PDplus presentation hosted by RiAus on science and myths of low level speeding, which will allow teachers to have access and put questions to scientists about their research and careers.

The RiAus PDplus Teacher Notes publication is produced by COSMOS magazine for the Royal Institution of Australia (RiAus).

See the RiAus website for further details and footage. www.riaus.org.au

This resource is made possible thanks to support from:

Other RiAus PDplus Teacher Notes

Food Security, Synthetic Biology, The Square Kilometre Array and The World Solar Challenge. These PDplus Teacher Notes are available on the RiAus website: http://riaus.org.au/programs/our-projects/riaus-pdplus

How to use the guide The notes offer both variety and flexibility of use for the differentiated classroom.

Teachers and students can choose to use all or any of the five sections – although it is recommended to use them in sequence, and all or a few of the activities within each section.

© 2012 COSMOS Media Pty Ltd, all rights reserved. No part of this publication may be reproduced in any manner or form for commercial purposes or outside of an educational setting. COSMOS, The Science of Everything™ is protected by trademarks in Australia and the USA. This guide was first published on 1 February 2012.

The ‘FIVE Es’ Model The guide will employ the ‘Five Es’ instructional model designed by Biological Sciences Curriculum Study, an educational research group in Colorado, USA. It has been found to be extremely effective in engaging students in learning science and technology. It follows a constructivist or inquiry based approach to learning, in which students build new ideas on top of the information they have acquired through previous experience.

Its components are:

Engage Students are asked to make connections between past and present learning experiences and become fully engaged in the topic to be learned.

Explore Students actively explore the concept or topic being taught. It is an informal process where the students should have fun manipulating ideas or equipment and discovering things about the topic.

Explain This is a more formal phase where the theory behind the concept is taught. Terms are defined and explanations given to models and theories.

Elaborate Students develop a deeper understanding of sections of the topic.

Evaluate Teacher and students evaluate what they have learned in each section.

Useful Websites Motor Accident Commision http://www.mac.sa.gov.au/

Transport statistics http://www.bitre.gov.au/info.aspx?NodeId=167

The University of Adelaide Centre for Automotive Safety Research http://casr.adelaide.edu.au/

Department for Transport, Energy and Infrastructure http://www.dpti.sa.gov.au/roadsafety

Street smart campaign for seniors http://www.raa.com.au/page.aspx?TerID=953

Road crash facts http://www.dpti.sa.gov.au/roadsafety/road_crash_facts/ sa_crashes

Road safety http://www.raa.com.au/page.aspx?TerID=1224

Road safety timeline http://casr.adelaide.edu.au/dbtw-wpd/Timeline/timelinesearch.htm

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Backgrounder

The science of speeding What does driving a car safely have to do with science? A lot - scientific principles determine how a car will move and react in different situations, and can help researchers understand how crashes can be avoided. Here is some of the science behind road safety.

Newton’s laws of motion

History of road safety

A painting of Isaac Newton from 1689.

Here’s a timeline of driving, road safety laws and our understanding of the physcis behind movement.

1330s

Italian inventors design wind-driven vehicles.

1687 Newton The law of inertia also shows us that loose objects in a car, such as luggage or pets can also be hazardous when a vehicle has to stop suddenly.

When a stationary car is hit from behind it can be suddenly pushed forward causing whiplash in the unsuspecting passengers as inertia causes their body to move rapidly forwards. Fitted head rests are now compulsory in cars in order to reduce injury by whiplash after rear end collisions.

Newton’s first law: inertia A stationary object will require a push or a pull to set it in motion, and we know this from our own experiences in life. When the net force on an object is zero, its speed and direction of motion will remain unchanged. This is true for objects both stationary as well as those already in motion.

An object that is in motion and has no other force acting upon it will remain in constant motion. We have very few examples of this in everyday life, as most objects in motion will slow down due to losing their energy because of friction.

The planets revolving around the Sun are one example of objects staying in constant motion.

Inertia means that a person travelling in a car at 60 km/h will keep moving at 60 km/h if the car stops suddenly. This means that they will be flung forward and can injure themselves hitting the steering wheel or windscreen. We use seatbelts to strap ourselves to the moving car to combat the law of inertia.

The seatbelt allows us to become one with the body of the car and so that we slow down with it.

Newton’s second law: F = ma The second law states that the force of an object is equal to the mass of the object times its acceleration. This means that if you exert the same force on two objects with different mass, they will accelerate at different speeds. We see this when a car breaks down at the traffic lights – it takes more people to push a truck out of the oncoming traffic than a mini.

Acceleration can be negative, for example when a driver hits the brakes and increases the friction to slow the car down. Here, a rapid increase in force results in a rapid negative acceleration.

Have you ever wondered why drivers hate to sit behind a huge truck at the traffic lights? Because a greater force is needed to accelerate an object with a greater mass, trucks take longer to accelerate than cars do. Drivers should be careful never to pull in front of a slowing truck because it will also take longer to negatively accelerate and could need the space in front to stop.

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publishes his three laws of motion in a book called Philosophiæ Naturalis Principia Mathematica, commonly known as the Principia.

Title page of the first edition of Principia.

1710s Thomas Newcomen builds an early model of a steam engine.

1760s

James Watt builds a pressurised steam engine.

1860s

Étienne Lenoir patented the first practical gas engine in Paris.

1890s

Henry Ford builds and sells his first cars.

1903 Safety glass is invented by

French chemist Edouard Benedictus.

1920s Road safety record

keeping begins and the National Safety Council is formed.

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1930s & 40s

The focus on safety grows with more countries and cities introducing drivers’ licenses and traffic lights.

WIKIMEDIA

While trying to identify a single rule by which the motion of all bodies could be calculated, Isaac Newton changed the way we think about the world when he described his three laws of motion. They were published in 1687 when Newton was 44 in a work commonly known as the Principia, which has often been considered by some to be the most significant scientific publication in history. The Principia was an accumulation of the mathematical principals worked on by many scientists including Hooke, Kepler, Galileo, Copernicus. It explained the universal law of gravitation and described Newton’s three laws of motion on which much of modern physics was built. Today, we can use Newton’s laws of motion to help us understand the physics of car crashes.

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Backgrounder Newton’s second law supports our awareness of road safety by showing us how the amount of force on a vehicle depends on its mass and acceleration. And conversely, that a vehicle’s mass and acceleration is what produces the force it transfers onto a pedestrian or tree trunk if the driver loses control.

If the forces acting on a car balance out, for example, if a driver hits the brakes and produces friction equal to the force the engine is applying to the wheels, then the force of the car is equal to zero (F = 0) and the car won’t budge.

Speed bumps, roundabouts and reduced speed limits are all designed to prevent drivers from going too fast.

Newton’s third law: action and reaction Newton stated that for every action there was an opposite and equal reaction.

For every push on a heavy box, the box pushes back equally. The box will only slide forward when the push on the box is greater than the push the box can return. When two vehicles hit each other with equal force, the damage to both will be equal. But when one vehicle has a greater mass and acceleration than the other, it will exert a greater force.

This law explains why your car moves forward when you step on the accelerator. The force exerted by the tyres on the road is matched by an equal and opposite force exerted by the road.

If that force is enough to overcome the car’s inertia, the car accelerates forward.

Energy of Car Collisions The law of conservation of energy states that energy is neither created or lost but can be transferred or transformed (converted) from one type to another.

Kinetic energy Kinetic energy is the energy of movement. The movement of the pistons in a car (converted from the chemical energy of petrol) is transformed into the car’s movement. When a car collides with a stationary object its kinetic energy is converted into energy that deforms the car and the object it hits. Heat and sound energy is also released in a crash.

If the mass of the vehicle accelerates due to a force acting on it, there will be an increase in kinetic energy. The more kinetic energy there is, the more that needs to be displaced when the vehicle collides. When the force acting on a vehicle is friction, the kinetic energy of

the car is converted to heat energy, and sound energy if the brakes squeal, due to the friction required to slow it down.

When Formula 1 cars crash, their external parts are designed to come to pieces and fly off in all directions while the driver remains strapped to the inner frame of the vehicle. The kinetic energy of the flying parts move a great deal of kinetic energy away from the vehicle so that there is less near the car that can harm the driver.

When two cars travelling at 50 km/h hit each other head on, the damage is the same as a car travelling 50km/h hitting a brick wall. It is easy to imagine the damage would be twice as bad because there is twice as much kinetic energy to convert due to the movement of both vehicles, but the damage is the same because there are two bonnets to absorb the kinetic energy.

1950s

Most countries require drivers to pass a test before getting behind the wheel of a car. Research into developing a crumple zone at the front of the car begins.

1960s

Anti lock brakes (to help prevent skidding) and rear head rests (to help prevent whiplash) are introduced into cars. The first crash test dummy ‘Sierra Sam’ is created.

In Australia, it becomes compulsory for all new cars to have fitted seatbelts.

Helmets become compulsory for motorbike riders.

1970s

Sierra Sam

Breath testing begins in Australia and seatbelts become compulsory for all passengers.

Australia introduces the first legislation requiring children to wear restraints when in vehicles.

1980s

Air bags are introduced in most car models. The first three speed cameras are used on Australian roads. A campaign begins in Australia to reduce default speed limit to 50 km/h.

1987 Earliest versions of

Electronic Stability Control (ESC), a technology utilised in vehicles to detect when the car is skidding.

ESC helps the driver correct the movement of the car by applying the brakes on the wheels so the driver has more control during the skid.

1990s 40 km/h zones near

schools in Australia are introduced.

2010s

Child restraint laws tightened to improve the safety of small children in cars.

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WIKMEDIA; iSTOCKPHOTO

2000s

National Road Safety Strategy developed in Australia with the aim of reducing road fatalities by 40%.

Backgrounder Elastic energy Elastic energy is energy similar to the kind stored in a spring or piece of elastic. While dodgem car collisions are somewhat elastic, where the kinetic energy of the moving car is absorbed by the spongy rubber and then converted back to kinetic energy as the dodgem car bounces away, collisions between metallic cars are not elastic. The kinetic energy of the moving

car is converted into the energy required to crumple the bonnet or other panels when the car crashes into something.

There has been a great deal of research into the crumple effect of the bonnet of a vehicle to allow it to absorb as much of the kinetic energy of a car crash as possible so that the energy is not transferred to the passengers where it can cause major injury.

Forces

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Forces are pushes and pulls and are needed for a car to move forward and to stop. As described in the third law of motion, it is the conflict between the force the tyres place on the road and the force the road exerts on the tyres that determines whether a car moves forward. If the force of the tyres on the road is enough to overcome the car’s inertia (e.g. on a clean, dry, road) the car accerlates forward. Forces are needed for movement to take place. It is easy to see how energy and force are interconnected in complex machines such as cars.

Friction Friction is a force that has an enormous effect on the motion of every day objects and is very important to road safety. Without friction, cars would have difficulty stopping. Anything that reduces friction, such as a wet slippery road or bald tyres threatens road safety.

Friction is the opposing force of two objects rubbing together and it produces heat. If road surfaces are rough there is a great deal of friction, and if the surfaces are smooth there is very little friction.

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SAM DOECKE, UNIVERSITY OF ADELAIDE

Careers, industry and courses

Profile: Sam Doecke Crash scene investigator and automotive engineer CASR, University of Adelaide When notice comes through from the South Australia ambulance service that there’s been a car crash, investigators from the Centre for Automotive Safety Research (CASR) at the University of Adelaide have to act quickly.

Part of their job is to reconstruct the impact scenario in order to better understand and improve road safety, but to do this, it’s critical that the accident site is preserved until they arrive.

“If the vehicles have been moved, or if we have no clear indication of where the vehicles ended up, we may not even proceed with the investigation,” explains Sam Doecke, an investigator and automotive engineer at the CASR. Once on scene, Doecke and his colleagues liaise with emergency personnel before carefully marking the position of the vehicles and, if fatalities have occurred, any position of bodies.

Next they mark and measure physical evidence such as skid marks, scrapes and gouges in the road surface, and debris. They then take photographs of the scene, speak to witnesses and involved parties if possible, and conduct a detailed engineering survey of the site.

Back in the lab, the team puts all the information into a searchable database, draws a scaled diagram of the crash site and begins the process of piecing the accident together, hoping to identify the contributing factors – and perhaps, determine who was at fault.

“If there are really nice critical speed marks, where a vehicle has lost control and left long, curving skid marks along the road, we can use those to do a fairly basic calculation,” says Doecke.

But for crashes involving multiple vehicles, where they collide and spin out, the researchers rely on 3D computer modelling.

“Technically speaking it’s not reconstruction, because it doesn’t work backwards – it works forwards, so it’s more like

simulating until we get something that matches the physical evidence,” he says. “We’ll estimate the speed, and the impact, then do a run and see how close that is to matching what we know happened.”

This requires knowing as much information about the vehicles as possible, including their make, model and year, in order to determine their exact dimensions and mass.

For Doecke, who began his university career studying mechanical engineering before switching to automotive engineering, working with cars was always in the game plan.

“I always had an interest in vehicles and tinkering with the design,” recalls the 27-year-old, who has had a long-held interest in motor racing, and just recently began venturing out on the track himself.

In his final year of study he took a course called automotive safety, which was run by some of the researchers at the CASR. “It was the first time I heard of the centre,” he recalls, “and it really caught my interest – it was something I could do on the automotive engineering side of things that could really have a positive impact.”

And at the CASR, the Australian-born researcher has had a chance to make some significant contributions; authoring studies on how the number of casualty crashes on South Australian roads can be reduced by targeting lowlevel speeders, and simulating pedestrian impacts to gauge injury scenarios.

For Doecke, research into road and automobile safety has heralded an unforeseen appeal. “I never really intended to get into research per se,” he says, “but what’s quite interesting about research is that there are constantly new topics – it’s not repetitive. There’s always a new problem to solve, or a question to answer.” – Myles Gough

“It was something I could do that could really have a positive impact.”

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Careers, industry and courses

Road injuries cause 600,000 deaths in Southeast Asia every year and are currently the ninth leading cause of death worldwide. Rebecca Ivers, director of the Injury Division at The George Institute for Global Health and an associate professor at the University of Sydney, directs a research program that focuses on injury prevention, with a strong emphasis on preventing injuries from road crashes.

She and her research team examine how many people are affected by injury and the resulting disability, the risk factors involved, and how these injuries can be prevented. “Our research measures the size of the problem, and evaluates effectiveness of prevention programs.”

Ivers initially studied optometry at the University of New South Wales and worked in the government’s eye health and trachoma programs in the Northern Territory after graduation.

“I really wanted to do something where I felt like I could make a difference to people’s lives,” she said. “That’s been the thing that’s driven me all along.”

While she was in the Northern Territory, she became interested in public health, especially among Aboriginal communities in remote areas.

She returned to university and undertook a master’s in public health at the University of Sydney, which then led to a PhD in injury epidemiology.

She initially focused on studying the falls and fractures resulting from poor vision and identifying the associated risks for older people, before moving on to injuries caused by poor vision and road crashes. Then in 2000 she oversaw DRIVE, a study that assessed the risk factors for over 20,000 novice drivers.

“In that study we found that risky driving is linked to an increased risk of crash, as is self-harm behaviour. We also found that young rural drivers are at far greater risk of single-vehicle crashes, which are more likely to result in serious injury than other crash types,” Ivers said.

Her studies have also focused working with the government to understand and prevent road injuries in the Aboriginal communities.

Statistics indicate that members of these communities are twice as likely to die in a road accident and are 40% more likely to be injured, which can be attributed in part to the bad roads, older cars and less access to emergency services in remote areas, according to Ivers.

REBECCA IVERS, UNIVERSITY OF SYDNEY

Profile: Rebecca Ivers Director of the Injury Division, George Institute for Global Health and Associate Professor at the University of Sydney

Some of her other projects are aimed at understanding and preventing injuries in China, India and Vietnam.

In the case of injuries resulting from road accidents, the higher diversity of vehicles – including bicycles and motorbicycles – on the roads in Southeast Asia and the low levels of road rule enforcement contribute to the high injury toll. “There’s a whole multitude of risk factors,” said Ivers. – Laura Boness

“We found that young rural drivers are at far greater risk of single-vehicle crashes, which are more likely to result in serious injury than other crash types.”

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Engage [Task] Imagine a crash 1. Draw or brainstorm what you think a car would look like hitting a wall at 80 km/h.

2. Now imagine and describe the same car hitting a wall at 100 km/h.

3. Predict what kind of damage would be done to two similar cars travelling at 50 km/h when they hit each other head on. Now watch this Mythbusters segment to find out if your predictions and those of Jamie and Adam were right:

http://www.youtube.com/watch?v=r8E5dUnLmh4

4. When you have watched the video, discuss the following:

a) What kind of energy is present in a collision? What is the starting energy and finishing energy in the collision shown on the mythbuster video?

b) In the equation Energy = ½ mv2 what do the ‘m’ and the ‘v’ represent?

d) How and why would it be beneficial to calculate the breaking distance of a car travelling at different speeds?

Can you think of a Mythbuster investigation to test the speed of the car and breaking distance? e) Newton’s third law of motion is mentioned in this segment, are Newton’s first and second laws of motion relevant to collisions? If so, where can you identify them at work in the video? f) Why do you think the speed limits in built up areas are lower than on a freeway? g) Do you think that if drivers understood the physics of car crashes better they would generally be more cautious when they are driving, such as not creeping over the speed limit? h) How have Jamie and Adam’s investigations helped our understanding of road safety?

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c) If the kinetic energy of a car moving forward is Energy = ½ mv2 then x2 the speed means x4 the stopping distance.

What does this mean for a car travelling at 50 km/h compared to 25 km/h?

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Explore (teacher’s page)

The aim of the Explore section is for the students to investigate some of the myths around road safety and ponder their possible impacts on the lives of their friends and family. It is intended that the students make their own discoveries about each myth as well as experience inquiry based science as they work around the stations in the room.

Each myth really is a myth so if students are unable to bust them with the crude equipment they have, it would be worthwhile developing one of these mini or pilot investigations into a full scientific investigation with strong emphasis on validity of methodology.

The equipment table below lists the equipment and preparation required.

Station

Materials List

Myth one Going a little over the speed limit is not unsafe.

About 20 toy figures such as green plastic soldiers that can stand alone Two toy cars Tape measure A4 sheet of paper

Myth two Small increases in speed do not increase the severity of a crash.

Toy car Ramp Something to crash the car into, such as plasticine that can be put up against a hard surface

Myth three It doesn’t matter if I go a little above the speed limit as long as everyone else is doing the speed limit.

Several marbles Long shoe box or equivalent with a smooth inner base Piece of card the same width as the box

Myth four Talking on a mobile phone while driving does not affect a driver’s concentration.

Ruler A set of simple arithmetic problems

Myth five Plastic figure Bull bars can reduce the impact on the Paper and/or cardboard to make a box to represent the car driver after their car hits a brick wall.

Wooden dowling rods and/or wire to build a bul bar Glue Sticky tape and string to attach the bull bar Solid surface to crash the ‘car’ into

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Explore (student activities) Myth one [Task] Bust the myth: going a little over the speed limit is not unsafe.

1. The A4 piece of paper represents a city square where there is a gathering of people who happen to be standing evenly

around the square. Set up the figurines provided by your teacher evenly around the square.

2. Consider the following statistics:

a) a car travelling at 50 km/h has a braking distance of 9.6 m. b) the same car with the driver reacting in the same way travelling at 55 km/h has a braking distance of 11.7 m.

3. Use the materials and information provided to carry out a simple investigation to find out if going 5 km over a 50 km/h

speed limit adds no extra danger to pedestrians.

4. What method did you use to attempt to bust this myth?

5. Were you able to bust this myth? What is your conclusion?

6. If you are unsure if you have busted this myth, what else could you do to bust it?

7. Another common road safety myth is that decreasing the speed limit has no effect on the number of crashes recorded.

From what you have learnt about myth one, suggest why this is a myth and not a fact.

Myth two [Task] Bust the myth: small increases in speed do not increase the severity of a crash.

1. Use the materials provided to conduct a simple investigation to find out whether increases in speed affect the impact of a

car crashing into a wall.

2. What method did you use to attempt to bust this myth?

3. Were you able to bust this myth? What is your conclusion?

4. If you are unsure if you have busted this myth, why do you think you didn’t bust it? What else could you do to test it?

Myth three [Task] Bust the myth: it doesn’t matter if I go a little above the speed limit as long as everyone else is doing the speed limit.

1. Pretend the marbles are cars and the bottom of the shoe box is a road.

2. Roll the marbles back and forth in the bottom of the box.

3. Examine what happens when the marbles are rolled down the bottom of the box at the same speed and when one marble is

going slightly faster.

4. Which situation will produce the least collisions?

5. Which method did you use to attempt to bust this myth?

6. Were you able to bust this myth? What is your conclusion?

7. If you are unsure if you have busted this myth, why do you think you didn’t bust it? What else could you do to test it?

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Explore (student activities) Myth four [Task] Bust the myth: talking on a mobile phone while driving does not affect a driver’s concentration.

Suggested method:

1. Hold the top of the ruler and get your partner to position their thumb and pointer fingers hovering over the 0 cm mark of

the ruler. Agree on a distance the thumb and pointer finger should be apart. Catching the ruler when dropped will simulate the concentration that is needed while driving.

2. Ask your partner some mathematical questions and make sure their responses are correct. Thinking about the questions

will simulate having an animated conversation on a mobile phone.

3. At a random point during the questioning, drop the ruler and record the distance it took them to catch the ruler.

This is the driver reaction time.

4. After repeating this a few times ask them to catch the ruler without doing the math questions.

Reaction while doing math problems (cm)

Reaction while not doing math problems (cm)

Average:

Average:

5. Were you able to bust this myth? What is your conclusion?

6. If you are unsure if you have busted this myth, why do you think you didn’t bust it? What else could you do to test it?

Math problems to use as a distraction similar to a mobile phone: 5+3(8), 19+2(21), 17-6(11), 5x3(15), 13+5(18), 27-3(24), 20÷4(5), 2x7(14), 6+7(13), 8÷2(4), 7+9(16), 11x3(33), 28÷7(4), 12÷3(4), 9x3(27), 12-4(8), 8+5(13), 6+5(11), 12x3(36), 19-5(14), 4x8(32), 2+27(29), 11-7(4), 32÷2(16), 9÷3(3), 14+4(18), 23+23(46), 37-12(25), 9+12(21), 8x8(64), 16+3(19), 16-3(13)

Myth five [Task] Bust the myth: bull bars can reduce the impact on the driver after their car hits a brick wall.

1. Use the soft materials provided to construct a box-shaped model car.

2. Attach a rigid bull bar to the front of this model car.

3. Conduct a simple investigation to find out if a bull bar attached to the front of a car can reduce the damage to a car

when it hits a solid object at high speed.

4. What method did you use to attempt to bust this myth?

5. Were you able to bust this myth? What is your conclusion?

6. If you are unsure if you have busted this myth, why do you think you didn’t bust it? What changes could you make to your

investigation in order to help you bust it?

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Explore (student activities) Summary 1. Which myth was the most fun to bust? Why? 2. Which myth(s) did you feel you had clearly busted?

3. Which myth(s) do you think need further testing before you could consider them ‘busted’?

4. How did your results compare with those of the rest of the class?

5. Can you think of any other road safety myths that you could bust?

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Explain (introduction)

In this section, we explain the science of road safety by getting students to read Cosmos articles and other information about road safety issues. This section suggests discussion topics and activities linked to those articles.

Before reading any of the articles there is a brainstorm activity to get students thinking about some of the unsafe behaviours that may lead to road accidents.

Each article will have its own literacy activities, which includes: • Glossary • Comprehension and summary • Questioning toolkit The articles include: Article one – Road crash statistics This article introduces the official statistics about Australia’s road crashes. It is a good place to start when thinking about why we can never give up on trying to improve safety on the roads. The information is taken from the National Road Safety Council website http://www.nrsc.gov.au/road_crash_statistics/index.aspx.

Article two – Motor Accident Commission (MAC) report This article mentions some of the research and strategies employed by the Motor Accident Commission of South Australia to communicate the importance of safety on our roads.

Article three – The physics of road safety This article discusses the interesting physics of road crashes and shows how science can debunk many of the myths we have about road safety. Examples include the myth that going a few km/h over the speed limit has no real safety risk.

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Explain (article one) Brainstorming [Task] Model the worst driver ever.

Around the figure and car below, draw or write some of the behaviours or actions of someone who is not a responsible driver.

Consider the following: • What they might have been doing just before they started driving that would compromise how well they drove.

• The kinds of activities they might try to do, or be forced to do while driving, that would reduce their focus and ability to drive well.

• Their general attitude to driving and other drivers on the road.

• Any unsafe conditions of their vehicle or their environment they are not responding to.

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When you have completed your ‘worst driver ever’ brainstorm, share your ideas with the rest of the class.

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Explain (article one)

Road crash statistics Road crashes result in about 1,500 deaths and 30,000 hospital admissions each year.

The annual cost to the national economy is estimated to be $27 billion.

Key Facts

Australian road deaths for 12 months over the last 10 years

• Every month, on average, over 100 people are killed on Australian roads.

• An average of 30,000 people are hospitalised every year as the result of road crashes.

months.

• On average at least four people die and 80 people are seriously injured on our roads every day.

• Over the last 40 years the national road fatality rate has fallen from around 3,800 deaths in the early 1970s to 1,500 in 2009, despite a substantial growth in population and vehicle usage.

• In 2010, there were 1,368 road deaths. This was an 8.2% decrease from the same 12 month period in 2009.

This graph shows the total number of road deaths in Australia from 2000 to 2010.

• Between Jan 2009 and Dec 2010, 47.4% of the fatal crashes occurred at speeds over 100km/h.

• Between Jan 2009 and Dec 2010, 58.4% of the crashes occurred during the day, compared to 41.6% that occurred at night.

• Between Jan 2010 and Dec 2010 the most road deaths were people between the ages of 40-59.

Data and graphs from: http://www.nrsc.gov.au/road_crash_statistics/index.aspx Percentage change in deaths in each State

Two graphs showing the percentage change in deaths in each state over the past 12 months and the last five years.

Left: Percentage change between the two 12-month periods ending December 2010 and December 2009. NT and ACT not shown. Right: Average annual percentage change based on the exponential trend from the year ending December 2005 to year ending December 2010.

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Explain (article one) Glossary [Task] Use the table to define any science or technical words that are related to this article.

Word

Definition

Hospital admission

Fatality

Average

Percentage

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about the guide Explain (article one) Summarising [Task] In your exercise book, complete the following questions and tasks.

1. Identify the number of people that die on Australian roads each year.

2. What is the average number of deaths per state or territory in Australia each year?

3. How many people are injured on Australian roads each day?

4. What is the estimated cost of road accidents to the Australian economy?

5. Under which conditions do the most road fatalities occur?

6. Draw a line of best fit on graph 1 over the top of the line graph provided using your ruler. Extend this line to predict the number of road deaths in 2015.

7. Which state has improved the most in relationship to reducing the number of road deaths over the last year?

8. Which state did not improve its road toll over the last five years?

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Explain (article one) Questioning toolkit [Task] Below are a series of discussion questions in the form of a questioning toolkit. Choose some or all of the questions, or ask some of your own.

Write your ideas and opinions relating to each of the different types of questions.

Inspired by Jamie McKenzie’s Questioning Toolkit - McKenzie, Jamie (2000) Beyond Technology, FNO Press, Bellingham, Washington, USA (www.fno.org/nov97/toolkit.html).

Type of question

Your ideas and opinions

Essential questions These are the most important and central questions.

They probe the deepest issues that confront us and can be difficult to answer.

Question: Why do road accidents occur? Why do you think the number of road fatalities have fallen over the last 40 years even though there are more drivers and cars on the road?

Subsidiary questions These questions help us to manage our information by finding the most relevant details.

Questions: Why do you think most road accident deaths in 2010 were people aged between 40 and 59? Why do you think most fatalities occur during the day? Why are there still fatalities when a car is travelling at less than 100km/h?

Hypothetical questions Questions designed to explore the possibilities, the ‘what ifs’? They are useful when we want to test our hunches.

Questions: Do you think that if less people drove and more people rode their bikes or walked to where they had to be each day that the number of road fatalities would decrease?

If the roads were just as busy at night as they are during the day do you think the majority of accidents would still occur during the day?

Provocative questions Questions to challenge convention.

Questions: Will it ever be possible to have a zero fatalities road accident outcome for any given year in the future? Why do you think driving is so popular even though it is one of the most unsafe ways to travel?

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Explain (article two)

Motor Accident Commission report

MAC

T

HE KEY THEMES of MAC’s road safety activity this year were a dedicated focus on road users most at risk, a desire to push the creative envelope and working with road safety partners in the development of a new Road Safety Strategy for South Australia.

MAC invested more than $10 million in road safety initiatives in 2010-11. Some of these were a first for South Australia and stimulated important community debate about road trauma.

While we remained focused on mature road safety issues including speeding, drink and drug driving, seatbelts and fatigue, this year we launched three new campaigns specifically targeting regional motorists, low-level speeding and motorcyclists.

MAC has also invested considerable time in researching and developing a campaign focusing on young drivers. Drivers aged 16 – 24 years have a crash rate double that of an average driver. They represent 14% of all licenced drivers, but generate over 30% of costs to the CTP Fund. The campaign will be launched in July 2011.

These target groups are grossly overrepresented in fatality and serious injury crash statistics. They also have distinct demographic and behavioural differences warranting unique campaign messages and approaches.

While some argued our campaigns were too controversial, our objective was to deliver messages that our target audiences would listen and relate to.

Extensive market research went in to the development of these campaigns to ensure our messages were well targeted and influential. To date, our post-campaign market research has shown our approach was on the right track.

‘Matemorphosis’, the regional campaign Regional South Australia continues to be over represented in road crashes, fatality and serious injury figures. They comprise 30% of the population yet account for 61% of those killed and 50% of those seriously injured. The high trauma rate is largely attributed to young males.

Just like on the footy field, mateship is the glue that unites regional communities.

This insight formed the basis for our ‘matemorphosis’ campaign. Launched in June 2011, the campaign featured real country people from the Callington Football Club, the location for the ad shoot. The campaign adopted a humorous approach but had a very serious message, encouraging young regional males to stop their mates from taking risks on the road.

As part of this important campaign, MAC implemented its Major Partnership with the South Australian Community Football League, to help reverse the disturbing trend of road trauma in regional South Australia.

‘Gear Up’, the motorcyclist campaign The ‘Gear Up’ motorcyclist campaign, launched in November 2010, highlighted the risks of riding without the appropriate protective clothing and once again featured FiveTime MotoGP Champion, Mick Doohan. It formed phase two of the motorcycle safety communication strategy.

It followed the successful first phase launched 12 months ago featuring a confronting television commercial showing the dangers faced by motorcyclists. The ongoing MAC campaign is the first to specifically target motorcyclists in South Australia with research showing they’re 30 times more likely to be killed on our roads than a motorist. Motorcyclists are fully exposed to all the elements and are also particularly vulnerable to injury if they’re involved in a crash.

‘Creepers’, the low-level speeding campaign Following on from the original ‘Creepers’ campaign developed in 2008, this refreshed campaign again focused on the damage that driving just a few kilometres over the limit can do. It featured three sequenced commercials showing a crash from the point of view of the driver, a witness and the victim. The campaign urged people to stick to the speed limit to stop creepers.

Road Safety in the community MAC has provided support to two major road safety initiatives aimed at school students for many years now, namely the South Australian Police Road Safety Education Program and the Schoolies Festival. This year MAC’s partnership with the Schoolies Festival was nationally recognised at the Sponsorship Australasia Awards in the Best Cause Related Sponsorship category.

MAC’s community presence was further strengthened through supporting the Good Sports program, a program to assist community-based sports clubs in regional South Australia to reduce alcohol- related problems, most importantly drink driving.

As an Australian-first, MAC supported the trial of a breakthrough communications technology in Adelaide.

The technology, known as Dedicated Short Range Communications, could dramatically reduce casualty crashes nationally by as much as 35%.

The road ahead Sadly, far too many South Australians lost their lives and suffered serious injuries in road crashes this year. However we were encouraged that total road casualties reduced by approximately 6% on the previous year. While this percentage sounds insignificant, it translates to 300 fewer people being injured on our roads.

MAC will be relentless in its road safety efforts to accelerate this downward trend both now and into the future.

This is an edited excert from the MAC annual report 2010-2011

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The Motor Accident Commission explains how it strives to improve the safety of the roads in this report.

Explain (article two) Glossary [Task] Use the following table to define any science or technical words that are related to this article.

Word

Definition

MAC

Casualties Demographic Market research

Protective clothing

Low level speeding

Schoolies

DSRC

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about the guide Explain (article two) Summarising [Task] In your exercise book, complete the following questions related to this article.

1.

Identify eight road safety initiatives of the Motor Accident Commission and describe them as well as you can using the information provided in the article. Use the table below to collate the information.

Road safety initiative

Description of road safety initiative

1

2

3

4

5

6

7

8

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Explain (article two) Questioning toolkit [Task] Below are a series of discussion questions in the form of a questioning toolkit. Choose some or all of the questions, or ask some of your own.

Write your ideas and opinions relating to each of the different types of questions.

Inspired by Jamie McKenzie’s Questioning Toolkit - McKenzie, Jamie (2000) Beyond Technology, FNO Press, Bellingham, Washington, USA (www.fno.org/nov97/toolkit.html).

Type of question

Your ideas and opinions

Essential questions These are the most important and central questions.

They probe the deepest issues that confront us and can be difficult to answer.

Question: What does a motor safety commission do? Why do we need organisations such as the Motor Accident Commission to communicate issues in road safety to us?

Subsidiary questions These questions help us to manage our information by finding the most relevant details.

Questions: Why might riding a motor bike be more dangerous than driving a car? What are some of the campaigns the other road safety commissions in other states in Australia have implemented?

Hypothetical questions Questions designed to explore the possibilities, the ‘what ifs’? They are useful when we want to test our hunches.

Questions: Do you think there is any reason for someone to drive unsafely? Do you think awareness campaigns like the ones mentioned in the report above would help you drive more safely or do you think safe driving is more about common sense? If you were the boss of a road safety commission, which campaigns would you promote?

Provocative questions Questions to challenge convention.

Questions: Is the money spent on road safety campaigns money well spent?

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the guide Explainabout (article three)

The physics of road safety Understanding the science of car crashes could help to create better drivers and reduce the number of deaths on the road, writes Myles Gough.

Using statewide surveys, they observed vehicle speeds at 127 different sites in South Australia, along urban and rural roads where speed limits ranged from 50 to 110 km/h; and they analysed crash sites where injuries or fatalities occurred.

While any speed reduction would likely reduce the incidence of injury and death, they found that the greatest overall benefit for preventing casualty crashes “will come from reducing speeds just above the speed limit in almost all cases.” The findings build on a 2001 report published by the same group at the university’s Centre for Automotive Safety Research. Using data from road crashes, they determined that the risk of being involved in a dangerous collision doubled with each five kilometre per hour speed increase above 60 km/h. Therefore, a car driving at 65 km/h would be twice as likely to be involved in a crash resulting in death or hospitalisation as a car abiding

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by the speed limit. A car racing at 70 km/h would see the risk quadruple.

Assessing the risk: reaction time It may seem insignificant, but hovering just a few km an hour above the speed limit could potentially be the difference between a safe stop and a costly collision.

The first thing to consider here is the human response time – this includes the fraction of a second it takes the driver to perceive a hazard on the road, such as a cyclist or animal, and then the amount of time it takes to react and apply the brakes. A typical reaction time for an alert driver is 1.5 seconds. This response time can vary, however, if a person is tired, under the influence of alcohol or drugs, or distracted. A recent study out of U.S.-based Texas A&M University, which observed drivers on an actual road test rather than inside a simulation, showed that reaction time could double if a driver

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F

or many people, driving a car becomes routine. They buckle themselves in and turn the key to ignite the engine; check their mirrors, the car is shifted into gear and seamlessly pulls away into traffic.

But sometimes on the road, drivers cheat, speeding just a few kilometres per hour over the designated limit in an effort to shave a few minutes off travel time.

Travelling 65 km/h in a 60 zone might seem like a relatively minor infraction, and likely won’t result in any speeding tickets, but it could increase the likelihood of being involved in a collision.

In a February 2011 study, researchers from the University of Adelaide concluded that the greatest prospective gain for reducing the number of car crash injuries would come from targeting low level speeders – those going just one to five kilometres per hour above the limit.

was text messaging. A simple scenario can illustrate how reaction time makes a difference. Suppose two cars are travelling along side each other on a road where the speed limit is 50 km per hour. One car is going at 50, the other at 55 km/h – roughly 10% faster. Both drivers perceive a hazard at the exact same time and respond in 1.5 seconds.

The first car, driving at the speed limit, will travel 21 m before the brakes are even applied. The car going at 55 km/h will travel 23 m in that same time. (If the reaction time took three seconds, then the distances double. Similarly, if the travel speed increases, so too will the reaction distance.) When examined in compound with other factors these relatively small distances become further magnified – and could mean the difference between life and death, especially if the hazard is a pedestrian wandering onto the road at precisely the wrong moment.

30.4 m versus 34.6 m for car two – that’s an increased distance of nearly 13%.

Had a hazard been present 32 m down the road, car one would have stopped in time, while the speeding car wouldn’t have been so lucky. “The increased speed does two things – because the reaction time is a fixed amount of time, rather than a fixed distance, a faster car travels further during that time,” says physicist John Storey from the University of New South Wales. “And because the distance required to stop is proportional to the square of the speed, then once you do hit the brakes, if you’re going twice as fast it will take four times the distance

Braking distance The next important thing to consider is the vehicle’s braking distance – how far it will travel at a given speed before ultimately coming to rest.

Many variables affect this distance, such as the efficiency of the braking system, the mass of the vehicle, tyre quality and the conditions of the road surface, and even the slope of the road.

An uphill stop will be aided by gravity, while a downhill gradient will add distance to the stop.

Examining the same scenario, assuming that both cars have an identical mass and braking system, and that the road is dry and flat, how long will it take each to stop? A simplified answer can be derived from the following equation: d = v2/2a.

Here, d represents the distance, v the initial velocity, and a represents the rate of deceleration and is determine largely by the grip of the tyres on the road. From the equation we can see that the braking distance is proportional to the square of the speed. So when the speed of a car is doubled, braking distance will quadruple.

It also makes a difference in our scenario.

Let’s assume that the rate of deceleration is 10 metres/second (m/s).

For the car travelling at 50 km/h (13.9 m/s) the braking distance will be 9.6 m.

For car two, driving at 55 km/h (15.3 m/s), the braking distance will be 11.7 m.

When we tack on the distance from the reaction times, car one will have travelled

Understanding the energy If a car is travelling faster or has a greater mass, it will also have more kinetic energy – this is the force of work needed to accelerate a body of mass (the vehicle) from a state of rest to a given velocity.

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Essentially this means, a faster or heavier vehicle, such as a truck or sport utility vehicle (SUV) will do more damage upon impact – to itself if it collides with an immovable object like a highway median, or to the collision partner, if that happens to be a compact car or something with a smaller mass. This is because the vehicle’s kinetic energy is ‘used up’ or transferred in the course of the collision. In physics there are two types of collisions. Elastic collisions, in which energy is conserved, would see cars travelling at speed collide and bounce off each other unscathed. Unfortunately, these collisions are hypothetical and don’t exist in our visible world. Car crashes are an ideal example, therefore, of the other type, inelastic collisions, where energy is used up and transferred into another form – such as heat or sound. “In the case of a typical car crash the energy is used up crumpling and deforming the metal – it takes energy to smash and bend steel,” says Storey.

Kinetic energy can be determined with the equation: ke = ½ m * v2. Here, ke represents kinetic energy in joules, m represents mass and v represents velocity.

In the scenario we’ve examined, where the second car is travelling 10% faster than the first, it will have 20% more kinetic energy.

If we suppose the car was travelling at 100 km/h, or double the speed of the first car, then the kinetic energy would increase fourfold. “That could make the difference between a minor ding in your car and a serious smash,” says forensic physicist Rod Cross from the University of Sydney.

“It could make the difference between a fracture in the skull or a guy been outright killed.”

Cross says the amount of energy required to crack a human skull from blunt force is roughly 50 joules of energy. to stop.” And if the road conditions or tyre quality are taken into account, these numbers could be greater still. “On a wet road, the difference between a new tyre and a bald tyre can be huge – increasing the stopping time by a factor of two,” says Storey. “And this is assuming that the driver is a skilled driver, and brings the car to a halt in the shortest distance.

What sometimes happens on a wet road is that the brakes lock up and the car skids,” he adds, noting that in icy conditions the stopping distance can be upwards of 10 times as great.

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Explain (article three)

Explain (article three) Cross, who has worked on several murder investigations, says the amount of energy required to crack a human skull from blunt force is roughly 50 joules of energy. “Let’s suppose you have only 40 joules involved in collision with the guys head,” says Cross, “he will probably end up with a headache but he won’t end up with a cracked skull.”

“If you have 60 joules of energy in the collision the guys skull will fracture, his brain will be injured, he will be injured internally and will probably die three days later.”

as a safety measure, but can actually pose more of a risk in a head-on collision.

“If you have a big rigid bull bar on the front of your car and you hit a wall, the stop is much more abrupt because there’s no give,” says Storey. “This subjects the drivers to much higher forces, which may exceed the lethal limit of what they can withstand.”

car suffering more damage. “If you collide a light object with a heavy object it’s the lighter object that rebounds more,” says Storey. “Think of a ball hitting a bat, the ball rebounds while the bat tends not to.”

Gauging the casualties This is important when judging the implications of a car striking a pedestrian. Technically, the pedestrian exerts the same amount of force on the car when the impact occurs.

However, because the car is much heavier, it hardly slows at all while the pedestrian is rapidly accelerated from zero up to the speed the car was travelling. This acceleration happens in the time it takes the car to travel the thickness of the human body – about 20 to 30 centimetres. Therefore, if a car is travelling at 10 m/s when the impact occurs and a pedestrian’s body is 25 cm thick, the impact lasts only 0.025 seconds, rapidly catapulting the struck pedestrian forward at 400 m/s.

Similarly, if vehicle passengers are not strapped in, they could theoretically be ejected from the vehicle at the same rate of acceleration. However, windscreens often slow their speed, but in doing so, result in a range of other horrific injuries.

If passengers are not strapped in, they could be ejected from the vehicle at the same rate of acceleration.

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Breaking down the collision In the event of a collision, the force acting on the car is that required to bring it to a complete halt.

Let’s consider a scenario where a car collides head on with an immovable object, such as a brick wall. “The shorter the distance that it comes to rest, the greater the acceleration force on the passengers or driver,” explains Storey. A car travelling at 80 km/h for instance would exert a greater force on passengers than a car travelling half that speed. Cars are deliberately designed, so that in these types of impact scenarios, the first half metre or so of the car’s body – its hood – collapses progressively. This part of the car is known as the ‘crumple’ or ‘crush zone’ and is designed to first absorb the initial shock of the crash, and then redistribute the energy from the impact so that it isn’t passed on to the passengers. The longer this crumple zone, the less the peak force of the impact, says Storey. This is the ground for one argument against ‘bull bars’, which are sometimes installed on the front of vehicle

“There’s a huge amount of engineering work that goes into designing the front of a car in order to protect the occupants – and one of the ways you can defeat all that good work is putting a ‘bull bar’ on,” he says.

An interesting paradox In looking at head on collisions, there is an interesting paradox to observe. If a car crashes at 50 km/h into a brick wall, is the crash identical to one with an oncoming car of the same size travelling the same speed?

The initial presumption is that the force of the crash involving two vehicles colliding head on would be greater because there is more kinetic energy. As it turns out, however, they are exactly the same.

“Each individual car carries its own kinetic energy into the collision, and assuming the cars are identical, then each of the cars individually absorbs its own kinetic energy,” says Storey. “Sure, you’ve got twice as much kinetic energy because there are two cars, but you’ve also got twice as many cars to spread the energy over.” However, if one car was heavier or faster, then the result would change, with the compact

Australia’s road toll According to statistics from Australia’s Bureau of Infrastructure, Transport and Regional Economics, there were 1,315 road deaths from August 2010 to August 2011. A breakdown shows that 607 of those deaths were drivers, 275 were passengers, 204 were motorcyclists, 189 were pedestrians and 39 were cyclists. Still the number has been declining over the last five years. It is 4% lower than the same 12-month period ending in 2010, and nearly 20% lower than 2007.

One alarming figure, however, is the disparity between male and female deaths, as men account for more than 70% of all fatalities on Australian roads.

From the point of view of an investigator, it is important to gather as much evidence as possible immediately after the crash.

If you’ve been involved in an accident, your initial reaction will likely be to call an ambulance, said Cross, but it’s also important to take photographs of things like skid marks on the road and to speak with witnesses.

“Often it is too late to come back six months later,” says Cross, “and so it’s important in terms of the physics of the problem to gather as much information right at the start as possible.”

about the three) guide Explain (article Glossary

[Task] Use the table to define any science or technical terms that are related to this story.

Term

Definition

Urban Rural Simulation Reaction distance Variables Gradient Equation Velocity Deceleration Proportional Kinetic energy Mass SUV Collision partner

Elastic collision

Inelastic collisions Joules Crumple zone

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about the three) guide Explain (article Summarising [Task] In your exercise book, answer the following questions.

1. Which branch of science conducts research on the effects of speeding and collision?

2. How do the following affect the braking distance of a car?

(a) The slope of the road

(b) How much water is on the road

(c) Ice on the road

(d) The condition of the cars’ tyres 3. Using the equation d = v2/2a, show all working out to demonstrate how the author of the article managed to calculate that a car decelerating (a) at 10 meters per second (m/s) from a velocity (v) of 13.9 m/s would take a distance of 9.6 m to stop after braking (d).

4. Using the equation d = v2/2a, what is the braking distance (d) if a car is travelling at 10 m/s (v) and decelerating at 5 m/s (a)?

5. Using the equation d = v2/2a what is the breaking distance of a car decelerating at 12 m/s from a speed of 14 m/s?

6. A driver is cruising along at a steady speed of 12 m/s. She sees a child’s soccer ball bounce out into the road 15 m in front of her and, worried that a child might be following after the ball, brakes immediately. She decelerates at 10 m/s. No child follows the ball, but is it possible she could hit the ball before she stops?

7. Define ‘kinetic energy’ and give some examples.

8. Describe what happens to the energy in a car crash when a car hits a wall?

9. What happens when two cars hit head on if:

a) one has greater mass than the other but is travelling at the same speed

b) they both have the same mass but one is going faster

c) they both have the same mass and are travelling at the same speed.

10. What effect does a bull bar have on the crumple effect if a car with one fitted hits a brick wall?

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Explain (article three) Questioning toolkit [Task] Below are a series of discussion questions in the form of a questioning toolkit. Choose some or all of the questions, or ask some of your own.

Write your ideas and opinions relating to each of the different types of questions.

Inspired by Jamie McKenzie’s Questioning Toolkit - McKenzie, Jamie (2000) Beyond Technology, FNO Press, Bellingham, Washington, USA (www.fno.org/nov97/toolkit.html).

Type of question

Your ideas and opinions

Essential questions These are the most important and central questions.

They probe the deepest issues that confront us and can be difficult to answer.

Question: Why does a few kilometres over the speed limit increase the risk of a road accident? How does a bull bar increase the damage to a car and driver after a head on collision?

Subsidiary questions These questions help us to manage our information by finding the most relevant details.

Questions: What sorts of things could cause a driver to brake really quickly and hence set them up for an accident? How can gathering information at the scene of an accident help prevent another accident?

Hypothetical questions Questions designed to explore the possibilities, the ‘what ifs’? They are useful when we want to test our hunches.

Questions: In the future if we all drive electric cars with a maximum speed of 40 km/h how much safer would the roads be?

If you were a road safety engineer what kinds of technology would you work on to help reduce the way the destructive energy in a car crash is spread to the car and not to the people in the car?

Provocative questions Questions to challenge convention.

Questions: Why do you think more males are injured or die in road accidents than females? Why do people continue to take risks when driving even though they are increasing the risk of an accident?

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Explain (summarising) Bringing it all together [Task] In your exercise book, complete the following activites related to all of the four articles.

1. What was your favourite article and why?

2. Create a mind map to show the relationship between all the different articles related to road safety.

3. List three big issues that you have learnt about from the articles.

4. Suggest why it is important to learn about the science behind road safety and low level speeding.

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29

h ac er

ou rc

e

r

es

’s

Te

Elaborate

About the Cosmos matrix What is the COSMOS Science Matrix?

A learning matrix such as the COSMOS Science Matrix is a flexible classroom tool designed to meet the needs of a variety of different learning styles across different levels of capabilities. Students learn in many different ways – some are suited to hands-on activities, others are strong visual learners, some enjoy intellectually challenging, independent hands-off activities, while others need more guidance. The matrix provides a smorgasbord of science learning activities from which teachers and/or students can choose.

Can I use the matrix for one or two lessons, or for a whole unit of study?

Either! The matrix is designed to be time flexible as well as educationally flexible. A time frame for each activity is suggested on the matrix. Choose to complete one activity, or as many as you like.

Is there room for student negotiation?

Yes! Students can be given a copy of the matrix and choose their own activities, or design their own activities in consultation with their classroom teacher.

Can I use the matrix for a class assessment?

Yes! You can set up a point system – perhaps one lesson equals one point. Students can be given a number of points to complete. If they choose less demanding activities, they will have to complete more of them.

What do the row headings mean?

Row heading

Description of activity

Scientific procedure

Hands-on activities that follow the scientific method. Includes experiments and surveys. Great for kinaesthetic and logical learners, as well as budding scientists.

Science philosophy

Thinking about science and its role in society. Includes discussion of ethical issues, debates and hypothetical situations. An important part of science in the 21st century.

Being creative with science

For all those imaginative students with a creative flair. Great for visual and musical learners and those who like to be innovative with the written word.

Science time travel

Here we consider scientific and technological development as a linear process by looking back in time or travelling creatively into the future.

‘Me’ the scientist

Personalising the science experience in order to engage students more deeply.

Communicating Using images to communicate complex science ideas. with graphics ICT

Exploring the topic using computers and the Internet.

What do the column headings mean?

1. Read and revise

2. Read and relate

3. Read and review

Designed to enhance student comprehension of information.

Gives the student the opportunity to apply or transfer their learning into a unique format.

Involves the more challenging tasks of analysing, and/or assessing information in order to create and express new ideas and opinions.

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Elaborate Scientific procedure

1. Read and revise – one or two lessons Choose a myth of your own or one of the mythbusting activities you undertook in the Explore section that you were unsure if you busted and, like Jamie and Adam often do, improve your methodology so that you can conduct a properly controlled scientific investigation.

Or Choose one of Newton’s three laws of motion and conduct an experiment to investigate it and show how it works in relation to road safety. A template is provided for this investigation. See Experiment 2 (below).

Note: If your school has an air car track and timing gates you may be able to use these in your investigation.

2. Read and relate – three or four lessons

Design, conduct and write up an experiment that demonstrates: Energy = ½ mv2 In other words, how 2x speed gives you 4x longer braking distance

3. Read and review – four or five lessons

Conduct an experiment to find out which kind of seatbelt is the safest – a lap only, a lap sash, or a full harness. See Experiment 1 (below).

Do teenagers have a bad attitude to driving or is this simply a perception some adults have? Why do some people want to show bravado on the road by speeding, even low level speeding?

Why do you think some people drive as if they are invincible?

Design a billboard advertisement to promote any one of the campaigns mentioned in the Motor Accident Commision report (article two) in the Explain section of the guide.

What were the observations that Newton made in order to devise Write a dialogue between two passengers in the back seat of a smart car with his three laws of motion? Describe each law. the new Dedicated Short Range Communication (DSRC) capabilities. The one passenger is explaining to the other how it works as radio signals inform the driver of potential dangers such as slow vehicles up ahead, fast approaching emergency vehicles, faulty traffic lights and roadwork hazards. Research DSRC technology to find out how it would communicate to a driver and assist them to avoid an accident.

Science philosophy

Being creative with science

The statistics in the first article of the Explain section show us that in the 1970s there were more road accidents than there are now, even though there were fewer drivers on the road. Make a list of all the reasons you think driving in the 1970s might have been more dangerous than now. Talk to a parent or grandparent about your ideas to see if they agree.

Imagine you are a science educator. Design a fun lesson or class activity to explain one of Newton’s three laws of motion or to explain what kinetic energy is and what happens to it when a car crashes. Make sure there is a practical activity to complement the theory. Check with your teacher to see if you can present the lesson to the rest of the class. Also, you could design a practical lesson to demonstrate how Energy = ½ mv2 works.

Why do you think that someone might drive unsafely and put themselves and someone else at risk? Is it unethical to drive unsafely?

OR Why do you think the road safety statistics might be slightly different depending on which source is used?

Science time travel

You are a road safety expert. Using what you have learnt from the articles, suggest why: the speed outside schools is 40 km/h at certain times of day; the speed limit for a P plate driver is lower than a full licence driver; an autobahn has a higher speed limit than a city road and a driver has to slow down near road works.

Collect the data in Experiment 3 (below) to create three graphs of a car moving at a constant speed and a car moving at varying speeds.

Why do road accidents happen? Are they the price we pay for having independent transport? Is it realistic to imagine a world without them? Watch the road trauma short films prepared by the RAA here: http://journeybeyondroadtrauma.org/static/short-films Then write a journal entry or a story to express any personal frustrations, confusions, ideas or fears you have about this aspect of our society that is so traumatic and disruptive.

Note: some viewers may find the content distressing.

‘Me’ the scientist

Use the information provided by one of the key facts in article one in the Explain section and visually present the statistic. You can use a pie chart, a line graph, or any other graphic that visually displays the information in the sentence.

If you double the velocity of a car you quadruple the stopping time. Come up with a creative way to visually show drivers how this works.

Communicating with graphics

Using Excel, tabulate the data in any of the three graphs presented in the first article of the Explain section.

Research a range of computer apps that are designed to promote road safety.

Which do you think could be the most useful and/or the most effective? Either design your own road safety app or describe in detail an idea for an app that would help improve safety on the road.

OR Do a Prezi (prezi.com) presentation of the kinds of car fittings and features that prevent injury, such as seat belts, inertial reel safety belts, airbags, head rests, head restraints, antilock brakes and any others you can think of. Show how each works in preventing injury during a collision.

Use a Venn diagram to compare road safety issues when driving a 60 tonne truck compared to driving a 1 tonne car. Include information in relation to; the percentage of lane space they take up, their mass, acceleration time, breaking distance, overtaking rules and speed limits.

Have speed cameras been effective in preventing road casualties? Imagine you are a road safety expert and gather data to find evidence as to whether speed cameras have actually reduced the number of road fatalities related to speeding. Sites such as the following will be useful. http://www.transportpolicy.org.uk/Cars/SpeedCameras/SpeedCameras.htm

If style and money were no object, design a safety car with internal and external features that would reduce the amount of injuries to the passengers. Consider how the kinetic energy from the impact could be converted or transferred to the car rather than to the occupants of the car. Ideas to consider: changing the length of the crumple zone of the bonnet, the position and size of airbags.

ICT

Find out how good your road safety is. Take the quiz at http://www.raa.com.au/driving_multi_new.asp?TerID=361 and http://www.raa.com.au/driving_giveway.asp?TerID=360 OR Practice driving at https://www.dot.ny.gov/programs/driver-safety Go to the test drive simulator and have a go at driving under the three different scenarios: - driving safely in work zones - safe summer driving - safe winter driving Note: this is an American site so you will have to drive on the right!

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Elaborate

Experiment 1

Which type of seat belt is the safest?

iSTOCKPHOTO

Background Information Depending on which type of vehicle you travel in, how old you are and which decade you spent most of your time in a car, there are three types of seatbelts you could have worn. Lap seat belts, like those on aeroplanes, are worn across the lap; lap sash seatbelts are those that have both a strap across the waist and one diagonally across the chest, such as the ones we commonly use today; and a harness seatbelt has straps over both shoulders and one horizontally across the chest.

Aim To find out which seat belt is the safest to have in a car.

Materials • Plastic doll (optional) • Plasticine • Cardboard box (such as a shoe box) that the doll can fit inside • String • Scissors • Masking tape Risk Analysis Risk

Precaution

Consequence

Sharp pointy scissors

Method 1. Cover the plastic doll with a thin layer of plasticine across the chest, head, arms and legs. Alternatively make a

plasticine figure.

2. Make two holes in the back of the box with the pointy end of the scissors.

3. Wrap a piece of string around the waist of the doll and then through the holes in the box so that the back of the doll is

attached to the box by the string ‘seatbelt’.

4. Put the lid on the box or fold lid over and secure with masking tape.

5. Hold the box so that the doll inside the box is facing the floor.

6. Let the box go so that it hits the floor.

7. Open the box and examine the markings on the plasticine caused by the impact and the seatbelt.

8. Record your observations in the results table.

9. Repeat steps 3 to 8 using a lap sash seatbelt on the doll.

10. Repeat steps 3 to 8 using a harness seatbelt on the doll.

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Elaborate Results Observations after head on collision (dropping the box) Seat belt type

Trial 1

Trial 2

Trial 3

Lap

Lap sash

Harness

Discussion How was this doll and box model able to show the effects of a real head on collision in a car?

How was this model limited in showing the effects of a real head on collision in a car?

Which seat belt caused the least damage to the doll?

Why do you think the other two seatbelts are used, if this one is the safest?

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Conclusion In your exercise book, write a conclusion that responds to the aim and summarises your results.

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Elaborate

Experiment 2 Re-busting a myth Background Information Jamie and Adam regularly design different methods each to bust a myth. They also like to rethink a method to bust a myth if they think their first method didn’t do it properly. In this activity you will choose one of the myths you had a go at busting earlier and see if you can design a method that, under more rigorous scientific investigation, you think will give you a more valid result. Think about the variable you need to control and if your method really does allow you to answer the research question. Use any extra materials you may need.

Myths to choose from: Myth one: wearing a seat belt makes no difference if the driver is going at the speed limit when they hit something.

Myth two: going a little over the speed limit is not unsafe.

Myth three: small increases in speed do not increase the severity of a crash.

Myth six: talking on the mobile phone while driving does not affect a driver’s concentration.

Myth seven: bull bars can reduce the impact to the driver after their car hits a brick wall.

Fill in the template below as you plan and conduct your experiment.

Myth to be busted in this experiment (Write the myth you want to have a go at re-busting below.)

Aim (Turn the myth into an experimental aim below.)

To find out...

Hypothesis (Say what you think will happen and why.)

Materials (Write a list of materials that you will use in this investigation.)

• • • • • • • • • •

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Elaborate Risk analysis (Identify any risks associated with this investigation. Ask your teacher to check your risk analysis before you continue with your investigation.)

Risk

Precaution

Consequence

Method (Write instructions for your investigation here so that someone independent could follow them and carry out the

exact same experiment that you did.)

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Elaborate Results (Design a table to collect the data taken from several trials. You may want to include an average of the trials).

Discussion Answer the following questions in your exercise book.

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2.

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Were your results similar to your hypothesis?

Do you think that you clearly busted this myth? Why or why not?

Identify any difficulties you had when trying to bust this myth and how you overcame them.

If there was no limit to the money, space, time and equipment that could be used to bust this myth, what method could you use?

Conclusion In your exercise book, write a conclusion that summarises your results and responds to the aim.

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Elaborate

Experiment 3 Calculating and graphing speed Background Information Whenever you ride in a vehicle, you rarely travel at a constant speed but continually accelerate and decelerate.

Any typical journey can be analysed and several characteristics, such as average speed, average velocity, instantaneous speed, acceleration and displacement can be measured. Complete the activity below to better understand the physics of moving around.

What to do Complete the following questions and activities in your exercise book.

1. Use a reliable source on the Internet, such as a science dictionary or a science text book to define the following terms and answer the following questions. Make sure you check they are correct before using them to complete the rest of the activity.

Speed: Velocity: Acceleration: Negative acceleration: Displacement: Distance: Instantaneous speed: Average speed: What is the difference between speed and velocity?

What is the difference between instantaneous speed and average speed?

What is the difference between distance and displacement?

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Elaborate 2. Examine the following scenario and imagine that this is where you have travelled today.

Friend’s house

120 m walk east in four and a half minutes. Start walking at 0.1 metres per second (m/s or ms–1) and accelerate to 0.6 ms-1 over the first minute.

Shop

80 m run north in 37 seconds.

78 m run south in 40 seconds.

Your house

Park 100 m stroll west in 5 minutes. At one point you are travelling at 0.5 ms-1 and you trip over and roll for 3 seconds before coming to a stop.

3. If you walked to your friends house and then to the shop and then back to your friends house:

a) what would the total distance you covered be?

b) what would your displacement be?

4. What speed were you running at when you ran from the shop to the park?

5. If average velocity is equal to displacement (in metres) over time (in seconds):

a) write the formula for average velocity.

b) calculate your average velocity from home to your friends house.

c) calculate your average velocity of the whole trip.

6. If average speed is equal to distance travelled (in metres) over time (in seconds):

a) write the formula for average speed.

b) calculate your average speed for the whole trip.

7. If acceleration is equal to the change in velocity over the change in time:

a) write the formula for acceleration.

b) calculate your acceleration when you leave your friends house and go to the shop. c) calculate your acceleration when you trip over when walking back home from the park.

8. Create a graph that visually shows your distance (vertical axis) over time (horizontal axis).

9. Now create a graph showing velocity over time.

10. Use the definitions and formulas you have learnt in this activity to write a question similar to the ones you have just

done using the scenario shown in the diagram in question one. Swap questions with your partner and see if you can

answer the question they have written.

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Elaborate (teacher’s page)

3. a) Distance = 80 + 120 + 120 = 320 m

b) Displacement = 80 + 120 = 120 = 80 m

4. Speed = 78/37 = 2.1 ms-1 5. a) Average velocity = displacement/time

b) Average velocity = 80/40 = 20 ms-1

c) Average velocity = 0/40+270+37+300 = 0/647 = 0 ms-1

6. If average speed is equal to distance travelled (in metres) over time (in seconds):

a) Average speed = distance travelled/time taken

b) Average speed = 80+120+78+100/40+270+37+300 = 378/647 = 0.58 ms-1

7. If acceleration is equal to the change in velocity over the change in time:

a) Acceleration = change in velocity/change in time

b) 0.5 ms-1 /60 ms-1= 0.008 ms-2 (or m/s2) c) Acceleration = –0.5 ms-1/ 3 ms-1 = –0.167 ms-2

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Evaluate

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Across 2. When driving long distances what should you take regularly?

4. What is the legal alcohol level of L plater drivers?

7. The ‘P’ on a P plate stands for?

8. What does a cross on a road sign mean?

10. When approaching a roundabout on a dual carriageway, you can only turn left from which lane?

11. Replace tyres if this is worn out.

13. You must always give way to cars to your ________.

15. You need to pass a test to be granted your _________.

17. At what time are native Australian animals most likely to wander onto the road?

18. What is the colour of caution on a traffic light?

19. This can make the roads slippery and increase braking distance.

RiAus PD plus: Speeding

Across: 2. breaks, 4. zero, 7. provisional, 8. crossroad, 10. left, 11. tread, 13. right, 15. license, 17. night, 18. amber, 19. rain Down: 1. Newton, 3. seatbelt, 5. forty, 6. mass, 9. double, 10. longer, 12. permit, 14. inertia, 16. kinetic

Speeding crossword

Down 1. Which scientist is responsible for the equation F = ma?

3. Everyone in the car must have their own __________.

5. What is the speed limit outside a school at the start of a school day?

6. What does the ‘m’ stand for in the equation F = ma?

9. Which kind of line(s) must not be crossed when driving?

10. The braking distance going downhill is ________ than when going uphill?

12. Before you can sit for your P plate license you need to get a learner’s ______ ?

14. Newton’s first law of motion.

16. The energy of movement.

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Evaluate Speeding word search D

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Find the following words hidden backwards, forwards, diagonally, downwards and upwards: air bags, attention, awareness, campaigns, caution, check mirrors, concentrate, drivers licence, education, give way, hazard, impact, reaction time, respect, responsibility, revive, road signs, road works, school zones, slow down, sober, speed limit, statistics

Create your own road safety quiz a) Ask each student to call out a word related to road safety. Record these on the board.

b) Each student must pick six words from the board and write a definition for each. c) Students then pick four more words from the board and write a paragraph describing them. They should highlight their

chosen words in the paragraph.

from the board. They should show links between words and write along lines connecting words to show how the terms are related.

d) Students create a concept map showing all they have learnt about road safety using at least half the words

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Evaluate Speeding individual unit review What about you?

Drawing

Sharing road trauma experiences as a path to an education about road safety and speeding can be an effective but sometimes confronting and personally upsetting process.

How did you cope with anything that you found upsetting?

How could you help a friend that may have been upset?

Create an image that summarises this unit of work for you.

Learning Summary Write five dot points of things that you learnt about road safety and speeding, particularly low level speeding.

Your philosophy What is your new philosophy about road safety and speeding? How has studying this unit of work on road safety changed your behavior as either a pedestrian, bike rider or driver? What can you do to make the road a safer place for yourself, your family and for fellow citizens?

More questions?

Metacognition

Write three questions that you still have about road safety, speeding or anything else related to this unit of study.

RiAus PD plus: Speeding

Which part of this unit of study on road safety and speeding had the biggest impact on you? Why?

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