NASCAR ENERGY UNIT LEARNING OUTCOMES LESSON 1: POTENTIAL ENERGY HIDDEN ENERGY

LESSON 2: KINETIC ENERGY ENERGY IN MOTION

LESSON 3: FRICTION AND ENERGY A DYNAMIC DUO

At the end of Lesson 1, students will be able to:

1. Define potential energy.

2. List the four main types of potential energy.

3. Identify forces that influence potential energy.

At the end of Lesson 2, students will be able to:

1. Define kinetic energy.

2. Identify forces that influence kinetic energy.

3. Describe the relationship between potential and kinetic energy.

At the end of Lesson 3, students will be able to:

1. Define friction.

2. Describe the relationship between friction and speed.

3. Describe the relationship between friction and racecar safety.

POTENTIAL ENERGY • KINETIC ENERGYFRICTION AND ENERGY

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THE ENERGY OFNASCAR

BEFORE YOU BEGIN: Have students complete the pre-assessment. Save the pre-assessments until the end of the unit to measure the growth in student knowledge.

PRE-ASSESSMENT ANSWER KEY: 1. C; 2. B; 3. D; 4. B; 5. A; 6. A; 7. C; 8. B; 9. B; 10. D

WHAT DO YOU KNOW ABOUT ENERGY?

1 What is potential energy?

A How fast an object can move B The force that makes an object moveC The unused energy stored in an

unmoving objectD All of the above

2 The potential energy of a car at the top of a ramp is affected by:

A the car’s shapeB the height of the ramp C the car’s speedD the length of the ramp

3 The force of gravity ________

A pushes objects away from EarthB slows objects down C causes objects to be pulled in two

different directionsD pulls objects toward Earth

4 True or false? Two objects with the same mass sitting at different heights have the same potential energy.

A True B False

5 What is kinetic energy?

A The energy of an object in motionB The energy in machinesC The energy stored in unmoving

objectsD None of the above

6 True or false? You can influence an object’s kinetic energy by changing its mass.

A True B False

This unit is all about energy. Share what you know about how energy works.

7 What are two factors in kinetic energy?

A Height and gravityB Gravity and speedC Speed and mass

D Mass and height

8 What is friction?

A A force that absorbs energyB The resistance that one surface

experiences when moving over another

C The pull of gravity D None of the above

9 What type of energy is created when two surfaces rub against each other?

A LightB HeatC SoundD All of the above

10 Why are the rules of energy important to racing?

A Because potential and kinetic energy help determine how quickly a racecar will go

B Because potential and kinetic energy help determine how much fuel a racecar will need to complete a race

C Because adjusting the factors that contribute to potential and kinetic energy can help a racecar go faster

D All of the above

PRE-ASSESSMENT

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NAME:

LESSON PLAN 1: POTENTIAL ENERGY HIDDEN ENERGY

TIME REQUIRED: 1 hour

MATERIALS: golf ball, large pan, flour, ruler

ACTIVITY AND RESOURCE SHEETS: Potential Energy Activity Sheets A and B

THINK

Central question: What is potential energy?

1. Introduce the concept of potential energy—energy that is stored due to an object’s position or condition. Explain that the word “potential” means having the ability to do something. Therefore, potential energy is energy that has not yet been used.

2. To illustrate the concept of potential energy, ask students to imagine a racecar sitting on the top of a steep hill. Tell students that in this position the car is loaded with a specific type of potential energy, called gravitational potential energy. Explain that when an object, like a racecar, is far above the ground, a force called gravity pulls it toward Earth’s surface. The greater an object’s height and mass, the harder gravity tugs on it. This type of potential energy is what pulls objects down a hill.

MOVE Central question: What affects the amount of potential energy an object has?

1. Tell students that you will demonstrate how height affects an object’s gravitational potential energy. Set a golf ball on the floor of your classroom. Ask students if the ball has any potential energy in its current state. (No, because there’s no distance for gravity to pull it toward Earth.)

2. Fill a large pan with a few inches of flour (leveled to create a flat surface) and place it on the floor. Raise the golf ball 12 centimeters (one foot) into the air. Ask whether the ball now has any potential energy. (Yes.) Drop the ball. Gently remove it from the pan, and have a volunteer measure the width of the impact crater left in the flour. Even

out the flour’s surface. This time, drop the ball from a height of one meter (three feet). Have a volunteer measure the new crater. Explain that raising the ball higher increased its potential energy, leading to a bigger impact.

BUILD Central question: What types of potential energy exist?

1. Hand out Potential Energy Activity Sheet A. Tell students that gravitational potential energy is just one type of potential energy. Have them complete the activity to learn about three other forms. Point out that each type plays an important role in how racecars function.

2. Now that students understand potential energy’s different forms, have them imagine a racecar sitting at a racetrack’s starting line. Ask: What forms of potential energy might the car have before it starts moving? Write their answers on your blackboard or whiteboard.

3. Explain that a car’s battery holds electric potential energy. When a driver starts the car, this energy is released as electricity to power parts inside the

car. The fuel in the car’s gas tank holds chemical potential energy. When the fuel burns, it undergoes a chemical reaction that unleashes energy to power the car’s engine and propel the vehicle around the track. (Fun fact: Just like a car, the human body relies on chemical potential energy stored in another type of fuel—food. By breaking down food, our bodies get the energy they need to survive.)

4. Describe how a racecar also has a suspension system between its wheels and its base. This system contains flexible springs that store elastic potential energy. When the car hits a bump in the road, the springs absorb the impact by compressing. Then they stretch to release the stored energy, pushing the tire back against the road. This helps prevent the car’s wheels from losing their grip on the track.

TEAM UP Central question: How do we identify the different types of potential energy around us?

Divide students into groups, and hand out Potential Energy Activity Sheet B. Explain that potential energy is all around us. Tell students to study the scene in the activity sheet and search for examples of the four different types of potential energy. See which group can identify the most objects with stored energy. Answers: Chemical: snacks in box in stands, gas, racecar, blimp; Gravitational: tire raised, food raised overhead, man holding flag, man climbing ladder; Electric: battery, lamppost, lights in the viewing boxes, television camera, air compressor; Elastic: muscles, tires.

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a

POTENTIAL ALL AROUND US

POTENTIAL ENERGY ACTIVITY SHEET A

NAME

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DIRECTIONS: There are four main types of potential energy. Read about each in the chart below. Then write down as many examples of each that you can think of. One is already done for you.

GRAVITATIONAL: energy stored in an object due to its height.

ELASTIC: energy stored in an object that can be stretched or squeezed.

ELECTRIC: energy stored as electricity.

CHEMICAL: energy stored in chemicals.

UNITS OF MEASURE: joules

Examples: a racecar coming off a bank,

UNITS OF MEASURE: joules

Examples: the springs that make up a racecar’s suspension system,

UNITS OF MEASURE: kilowatt-hours

Examples: a racecar’s battery,

UNITS OF MEASURE: calories (food), joules, horsepower-hours (vehicles)

Examples: burning fuel inside a racecar’s engine,

DIRECTIONS: A day at the racetrack is full of potential energy. Look at the scenes below on race day and find examples of the four main types of potential energy. How many examples can you find?

A DAY AT THE RACESPOTENTIAL ENERGY ACTIVITY SHEET B

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1 Chemical:

2 Gravitational:

3 Electric:

4 Elastic:

ALONG THE TRACK

INSIDE THE PIT

LESSON PLAN 2: KINETIC ENERGY ENERGY IN MOTION

THINK Central question: What is kinetic energy?

1. Have students consider what happens to potential energy when it’s released from its stored state. Explain that energy can’t be created or destroyed. It can only change from one form to another. Potential energy is often converted into another type of energy called kinetic energy. Kinetic energy is the energy of motion. It can also transform back into potential energy. For example, you’d use kinetic energy to lift a ball to the top of a ramp. That energy would be stored in the ball as potential energy.

2. Ask: Which racecar do you think would have the greatest kinetic energy: a car cruising into a pit stop at 89 kilometers (55 miles) per hour or one racing across the finish line at 322 kph (200 mph)? Have students discuss their thinking. Explain that the faster a car is going, the more kinetic energy it will have.

MOVE Central question: What factors affect kinetic energy?

1. State that speed is not the only factor that affects how much kinetic energy a moving object will have. Have students check out this demonstration to learn how mass also influences an object’s energy of motion.

2. Select a light object (such as a pencil) and a heavy object (such as a pack of index cards). Tie a string around each object, leaving a one-meter-long (three-foot-long) piece attached. Have a student volunteer hold the light object in his or her right hand one meter (three feet) above the ground. He or she should hold the other end of the string in his or her left hand so it is stretched horizontally. Have another student

the track, it’s like the car is speeding down a hill. The potential energy transforms into kinetic energy.

2. Three factors affect how much potential energy the racecar has at the top of a bank: the car’s height, the car’s mass, and the force of gravity. Explain that NASCAR engineers consider the height of racetrack banks when considering how the cars will behave. In addition, all racecars must weigh 3,300 pounds (without a driver). Having identical masses makes sure the cars are competitively equal. NASCAR enforces these rules by inspecting each car before each race. (If you have not explored aerodynamics with your class, refer to the Three Ds of Speed unit to learn how NASCAR drivers and engineers use science to create more speed on the track.)

3. Tell students they will team up to test how potential energy turns into kinetic energy. Hand out the Kinetic Energy Activity Sheet and the experiment materials. After groups have completed the experiment, have them present their results and discuss as a class.

TEAM UP Central question: How does kinetic energy influence NASCAR engineers’ choices?

Explain that NASCAR engineers spend a lot of time thinking about kinetic energy for both racecar performance and safety. Divide students into teams, and tell them to put on their make-believe “engineer caps.” They’ll need to imagine all the parts of a NASCAR race from start to finish—that includes designing cars and tracks, installing safety protections for drivers and fans, understanding how vehicles will perform while racing and when making pit stops, and even things that could possibly go wrong during a competition. Have students create a list of the roles kinetic energy plays in each stage of racing.

TIME REQUIRED: 1 hour

MATERIALS: String, heavy and light objects (such as a pencil or a pack of index cards), paper cup, masking tape, ruler, textbooks, cardboard, toy car or completed car from the Three Ds of Speed

ACTIVITY SHEETS: Kinetic Energy Activity Sheet

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place a paper cup on the floor just under the first student’s left hand, and mark the spot on the floor with a piece of masking tape. Tell the first student to let go of the object so it swings and collides with the paper cup (this may take a few tries to hit the cup). Have your other volunteer measure the distance the paper cup moved after the swinging object struck it.

3. Repeat the process with the heavier object. Students will observe that the heavier object made more of an impact than the lighter one, moving the cup farther away. This is because the heavier object had a greater kinetic energy.

BUILD Central question: How can potential energy become kinetic energy?

1. Reveal that racecars don’t just go forward and side to side as they pass each other on the racetrack, they also go up! NASCAR racetracks aren’t completely flat. On turns, the tracks are actually tilted. These banks help drivers maintain grip and speed as they whip around corners. Explain that when a driver is high on a bank, his or her car has a lot of potential energy. When a driver comes out of a turn and down onto the flat portion of

PROCEDURE: 1 Use books and cardboard to make a ramp. Use tape to secure both ends of the ramp to the books

and floor.

2 Measure the height of the ramp. Record the height under “Run 1” in the table below.

3 Place your car at the top of the ramp. Release the car. Once it stops moving, use the ruler to measure how far it rolled from the end of the ramp.

4 Add two textbooks to raise the height of your ramp. Then repeat steps two and three.

DIRECTIONS:Try this experiment to see how changing a car’s potential energy changes its kinetic energy.

PREDICT: Will a car racing down a ramp travel a shorter or greater distance if you raise the ramp’s height? ____________

___________________________________________________

___________________________________________________

___________________________________________________

RAMP IT UP

CONCLUSIONS:Answer these questions on a separate sheet of paper.

1 What happened when you raised the height of the ramp? Was your prediction correct?

2 Did raising the ramp’s height give the car more or less potential energy? Explain your answer.

3 Did the car in Run 1 or 2 end up with more kinetic energy? How could you tell?

KINETIC ENERGY ACTIVITY SHEET

NAME

DATA:

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Ramp Height Distance Car Rolled

Run 1

Run 2

GATHER YOUR MATERIALS:

Books, cardboard, completed car from the Three

Ds of Speed, tape, ruler

3. While friction can increase safety in racecars, it can cause problems, too. Due to a racecar’s high speed, there is a lot of friction where the tires rub against the road. The friction takes some of the racecar’s kinetic energy and converts it into heat energy. As a result, the racecar’s tires become very hot and will eventually fall apart. This is why racecar teams change tires multiple times during a race.

MOVE

Central question: What type of energy is created by friction?

1. Demonstrate how friction is heat energy by having students rub their hands together. Point out that the more vigorously they rub them, the warmer their hands will become. Any two surfaces that rub together will create heat.

2. Point out that friction depends on a force pushing two surfaces together. For example, when you rub your hands together, the more force you apply, the more friction and heat you will create. If there is no force, there is no contact; therefore, there is no friction.

BUILD Central question: What types of surfaces create the most friction?

1. Distribute the Friction and Energy Activity Sheet and tell students that they will build a high-friction racetrack to demonstrate the effects of friction on a rolling car. Point out that any contact between atoms or

molecules will create friction. Rough surfaces have more matter exposed than smooth surfaces—more nooks and crannies—and this creates more available spots for possible friction.

2. After the discussion, have students create a cause-and-effect chart that analyzes the impact of friction on their experiment and explain the effects of friction on kinetic energy.

TEAM UP Central question: How can we diminish friction?

Explain that racecar engineers study friction to improve the speed of racecars. They work to diminish friction so the cars can move quickly, but they don’t want to get rid of friction altogether, because friction allows the cars to slow down and stop. Divide students into problem-solving teams and give them the task of brainstorming ways to remove friction from their daily lives. Their lists should include sources of friction around them and an explanation of how removing that friction would make their lives better. If they need idea prompts, share this list of everyday items that experience friction: car tires, skateboard wheels, train tracks, swinging doors, zippers. Have groups present their recommendations to the class.

AFTER THE UNIT: Once you have finished all three lessons, have students complete the post-assessment and compare their responses to the pre-assessment.

POST-ASSESSMENT ANSWER KEY: 1. B; 2. D; 3. D; 4. B; 5. B; 6. C; 7. A; 8. A; 9. B; 10. D

THINK

Central question: How are kinetic energy and friction related?

1. Ask students to define friction—the resistance that one surface experiences when moving over another. We experience friction often in our everyday lives. For example, friction occurs between a car’s tires and the road. Less friction allows cars to move more quickly and more friction slows cars down.

2. To make sure racecars stay on the track as they speed around turns, NASCAR engineers work hard to make sure the cars are always making solid contact with the ground—they fine-tune the car’s aerodynamics, tires, and the surfaces of the road to create a safe grip, or friction, for the speeding cars. NASCAR tires are smoother than the tires on everyday vehicles. This allows the cars to reach higher speeds. In addition, NASCAR tracks have different surfaces, like asphalt or concrete, which affect tire friction and performance.

LESSON PLAN 3: FRICTION AND ENERGY A DYNAMIC DUO

TIME REQUIRED: 1 hour

MATERIALS: Cardboard, toy car or completed car from the Three Ds of Speed, tape measure or rulers, tape, various surfaces (such as tinfoil, fine sandpaper, rough sandpaper, waxed paper, carpet)

ACTIVITY SHEET: Friction and Energy Activity Sheet

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How does friction impact speed? Friction is the resistance that happens between surfaces that are touching. As soon as a car starts rolling, friction strikes! The spot where the car’s tires hit the racetrack is where the friction happens.

You can’t often see friction, but it’s all around us. Use this experiment to create friction, measure it, and analyze its impacts.

PROCEDURE: 1 Build a simple incline to roll your car down.

Put one end of your cardboard on a stack of books. In front of the ramp, clear a racetrack for the car to travel. Curl the bottom of the ramp, so the car’s impact with the floor is as gentle as possible.

2 Place your car at the top of the ramp and release the car. When it stops rolling, measure how far it traveled from the bottom of the ramp. Record your data in the chart on the right.

3 Place the first surface you will test at the bottom of your ramp. Measure how far the car travels when it rolls over your first surface. Follow these same steps to test your two other surfaces. Record all your data.

THE FORCE OF FRICTION

CONCLUSIONS:Answer these questions on a separate sheet of paper.

1 What causes friction? Which surfaces caused the most friction and which surfaces caused the least friction?

2 How did you witness friction in this experiment? What piece of data was evidence of friction?

3 In your own words, summarize how friction affects a moving object’s kinetic energy.

FRICTION AND ENERGY ACTIVITY SHEET

NAME

DATA:

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Surface Distance

Floor

Surface 1_________

Surface 2_________

Surface 3_________

GATHER YOUR MATERIALS:

Cardboard, completed car from the Three Ds of Speed, ruler, tape, three different

surfaces such as sandpaper, tinfoil, and carpet

POST-ASSESSMENT

1 The energy stored in an object due to its position or condition is known as _____.

A Kinetic energyB Potential energyC FrictionD All of the above

2 Mass, gravity, and height are the variables that shape _____.

A SpeedB FrictionC Kinetic energyD Potential energy

3 Increasing an object’s _____ will increase its potential energy.

A GirthB ForceC WidthD Mass

4 Imagine two objects of the same mass sitting on a bookshelf. If you take one of them and move it to a lower shelf, you have _____.

A Increased its potential energyB Decreased its potential energyC Caused no change in its potential

energyD Removed all energy from the object

5 The energy of an object in motion is known as _____.

A Potential energyB Kinetic energyC Mechanical energyD Nuclear energy

Share what you know about the influence of energy on the objects in the world around us.

6 Speed and _____ are the factors that affect kinetic energy.

A HeightB GravityC Mass

D Temperature

7 True or false? Imagine a delivery truck is driving down the road and suddenly it loses half of its load. The truck’s kinetic energy has decreased.

A True B False

8 The resistance that occurs when one surface rubs against another is called _____.

A FrictionB Free energyC GravityD Acceleration

9 A racecar’s tire brakes often glow red because friction generates _____.

A Kinetic energyB HeatC Potential energyD Acceleration

10 Knowing about potential and kinetic energy helps racecar engineers _____.

A Understand how the two are relatedB Design cars that go fasterC Reduce the effects of frictionD All of the above

WHAT DID YOU LEARN ABOUT HOW ENERGY WORKS?

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NAME:

BUILD A RACECARASSEMBLY SHEET A

BEFORE YOU BEGIN:

COMPLETE YOUR CAR:

Color or personalize your racecar.

STEP 1:

STEP 3:

STEP 2:

STEP 4:

Flip the car over. Fold up the sides and connect the tabs using the split ends.

Connect the front and back of the car by sliding the top tab into the top slot. Reinforce the roof of your car with tape.

Fold up the front and the back of the car to cover all the tabs. Secure the hood and trunk by tucking the semicircles into the front and back openings.

Cut two 1½-inch pieces from the plastic straw to match the width of the car. (Note: Save the final piece of straw for the Lesson 2 experiment.) Flip the car over and tape the straw pieces along the guidelines on the bottom of the car.

GATHER YOUR MATERIALS:car template, wheels, axles, plastic straw,

scissors, ruler, tape, markers

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Press one wheel firmly to one end of the axle. Thread the axle through the front straw, then put second wheel on axle. Repeat with the rear wheels and axle. Now your car is ready to roll.

BUILD A RACECARASSEMBLY SHEET A

BEFORE YOU BEGIN:

COMPLETE YOUR CAR:

Color or personalize your racecar.

STEP 1:

STEP 3:

STEP 2:

STEP 4:

Flip the car over. Fold up the sides and connect the tabs using the split ends.

Connect the front and back of the car by sliding the top tab into the top slot. Reinforce the roof of your car with tape.

Fold up the front and the back of the car to cover all the tabs. Secure the hood and trunk by tucking the semicircles into the front and back openings.

Cut two 3-inch pieces from the plastic straw. (Note: Save the final piece of straw for the Lesson 2 experiment.) Flip the car over and tape the straw pieces along the guidelines on the bottom of the car.

Thread a candy over each straw end. Fold a small piece of tape over the end of each straw to keep the candies in place. (Note: The tape shouldn’t prevent the candies from spinning.) Now your car is ready to roll.

GATHER YOUR MATERIALS:car template, plastic straw, scissors, ruler, four round

candies with holes in their centers, tape, markers

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NEXT GENERATION SCIENCE STANDARDS

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: FR

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GRADE 5Science and Engineering Practices

Planning and Carrying Out Investigations

Plan and conduct an investigation collaboratively to produce data to serve as the basis for evidence, using fair tests in which variables are controlled and the number of trials considered.

Make observations and/or measurements to produce data to serve as the basis for evidence for an explanation of a phenomenon or test a design solution.

Constructing Explanations and Designing Solutions

Construct an explanation of observed relationships.

Obtaining, Evaluating, and Communicating Information

Communicate scientific and/or technical information orally and/or in written formats, including various forms of media as well as tables, diagrams, and charts.

GRADES 6–7Science and Engineering Practices

Planning and Carrying Out Investigations

Conduct an investigation and/or evaluate and/or revise the experimental design to produce data to serve as the basis for evidence that meets the goals of the investigation.

Engaging in Argument From Evidence

Construct, use, and/or present an oral and written argument supported by empirical evidence and scientific reasoning to support or refute an explanation or a model for a phenomenon or a solution to a problem.

Obtaining, Evaluating, and Communicating Information

Communicate scientific and/or technical information (e.g., about a proposed object, tool, process, system) in writing and/or through oral presentations.

Physical Sciences

Motion and Stability: Forces and Interactions

Plan an investigation to provide evidence that the change in an object’s motion depends on the sum of the forces on the object and the mass of the object.

Energy

Construct and interpret graphical displays of data to describe the relationships of kinetic energy to the mass of an object and to the speed of an object.

Construct, use, and present arguments to support the claim that when the kinetic energy of an object changes, energy is transferred to or from the object.

Source: NGSS Lead States. 2013. Next Generation Science Standards: For States, By States. Washington, DC: The National Academies Press.

THE ENERGY OF NASCAR STANDARDS SPOTLIGHT

The Energy of NASCAR unit covers overarching concepts relevant to a range of science principles that can be easily applied to your state’s science standards.