Bumper Bumper CarsCars

By SheaBy Shea

QuestionQuestion How do different kinds of bumper How do different kinds of bumper

materials affect how much energy materials affect how much energy is transferred to the “passenger” is transferred to the “passenger” in a car collision?in a car collision?

HypothesisHypothesis If a car is rolled down a ramp with different If a car is rolled down a ramp with different

bumper materials (no bumper, foam packing bumper materials (no bumper, foam packing peanuts, bubble wrap, rubber) and crashed into peanuts, bubble wrap, rubber) and crashed into a barrier, then the car with the bubble wrap for a barrier, then the car with the bubble wrap for the bumper will cause the least amount of the bumper will cause the least amount of energy to be transferred to the “passenger” energy to be transferred to the “passenger” because the bubble wrap will probably because the bubble wrap will probably compress the most gradually and that will cause compress the most gradually and that will cause a gradual change in speed, which my research a gradual change in speed, which my research says is better than a quick change in speed.says is better than a quick change in speed.

MaterialsMaterials rectangular wood block (16.9 grams)rectangular wood block (16.9 grams) Pasco GO car (229 grams)Pasco GO car (229 grams) metal rampmetal ramp support for rampsupport for ramp 2-cm high barrier to put at the end of ramp2-cm high barrier to put at the end of ramp meter stickmeter stick bumper materials: foam packing peanuts, bumper materials: foam packing peanuts,

bubble wrap, half of a rubber ballbubble wrap, half of a rubber ball

ProcedureProcedureDo this procedure for each type of bumper material (no Do this procedure for each type of bumper material (no

bumper, foam, bubble wrap, rubber):bumper, foam, bubble wrap, rubber): Put wooden block on the car.Put wooden block on the car. Put car on the top of a ramp that has been raised 15 Put car on the top of a ramp that has been raised 15

cm off the ground. The ramp should have a 2 cm cm off the ground. The ramp should have a 2 cm high barrier at the bottom to stop the car.high barrier at the bottom to stop the car.

Let the car goLet the car go without without pushing it. pushing it. Measure the distance the center of the block goes Measure the distance the center of the block goes

after the car hits the barrier.after the car hits the barrier. Record data.Record data. Repeat steps 1-5 four more times.Repeat steps 1-5 four more times.

VariablesVariablesIndependent variable:Independent variable: The type of bumper materialThe type of bumper materialDependent variable:Dependent variable: How far the block of wood (“passenger”) goes after How far the block of wood (“passenger”) goes after

the collisionthe collisionControlled variables:Controlled variables: Same carSame car Same length and angle of trackSame length and angle of track Same block of woodSame block of wood Same starting position and speed of cartSame starting position and speed of cart Same position of barrierSame position of barrier

Data ChartData ChartNo Bumper Foam Bubble Wrap Rubber

Trial 1 42.5 cm 30.5 cm 36 cm 36.5 cm

Trial 2 62.5 cm 48.5 cm 35 cm 65 cm

Trial 3 46.5 cm 39 cm 35.5 cm 47.5 cm

Trial 4 54 cm 31 cm 48.5 cm 27.5 cm

Trial 5 31.5 cm 37 cm 47.5 cm 37.5 cm

Average 47.4 cm 37.2 cm 40.5 cm 42.8 cm

GraphGraph47.4

37.2

40.542.8

0

5

10

15

20

25

30

35

40

45

50

Average Distance Traveled (cm)

No Bumper Foam Bubble w rap Rubber

Bumper Materials

How far a wooden block on a car with different bumpers will go after a collision

Written Written ExplanationExplanation

The data shows that the average distance the block The data shows that the average distance the block

travels with no bumper is 47.4 cm, for the foam bumper travels with no bumper is 47.4 cm, for the foam bumper it is 37.2 cm, for the bubble wrap bumper it is 40.5 cm, it is 37.2 cm, for the bubble wrap bumper it is 40.5 cm, and for the rubber bumper it is 42.8 cm.and for the rubber bumper it is 42.8 cm.

The foam and bubble wrap kept the most amount of The foam and bubble wrap kept the most amount of energy from being transferred to the “passenger” (the energy from being transferred to the “passenger” (the block), but the foam made it (on average) go 3.3 cm block), but the foam made it (on average) go 3.3 cm less than the bubble wrap – which means that foam is less than the bubble wrap – which means that foam is the best bumper material because it causes the least the best bumper material because it causes the least amount of energy to be transferred to the “passenger”.amount of energy to be transferred to the “passenger”.

ConclusionConclusion My hypothesis was, if I rolled a car down a My hypothesis was, if I rolled a car down a

ramp with different bumper materials (no ramp with different bumper materials (no bumper, foam packing peanuts, bubble wrap, bumper, foam packing peanuts, bubble wrap, and a rubber ball), that the car with the bubble and a rubber ball), that the car with the bubble wrap for the bumper would cause the block of wrap for the bumper would cause the block of wood (the “passenger”) to go the least distance wood (the “passenger”) to go the least distance after a collision. That is because the bubble after a collision. That is because the bubble wrap would probably compress the most wrap would probably compress the most gradually, and my research says that it’s better gradually, and my research says that it’s better to have a gradual change in speed, which the to have a gradual change in speed, which the gradual compression would make.gradual compression would make.

ConclusionConclusion The results proved my hypothesis was incorrect. The actual The results proved my hypothesis was incorrect. The actual

answer is the foam packing peanuts prevented the least amount answer is the foam packing peanuts prevented the least amount of energy being transferred to the “passenger” (the block). The of energy being transferred to the “passenger” (the block). The foam’s average distance traveled (37.2 cm) was the least, which foam’s average distance traveled (37.2 cm) was the least, which shows that that it absorbed the most amount of energy. The shows that that it absorbed the most amount of energy. The bubble wrap’s average distance traveled (40.5 cm) was only 3.3 bubble wrap’s average distance traveled (40.5 cm) was only 3.3 cm larger than the foam’s distance, but in a real life crash this cm larger than the foam’s distance, but in a real life crash this distance would have been a bigger difference - so I did not count distance would have been a bigger difference - so I did not count them as being basically the same. The rubber, I think, would them as being basically the same. The rubber, I think, would make a bad bumper in real life because the rubber seemed make a bad bumper in real life because the rubber seemed unpredictable in helping with the crash because the unpredictable in helping with the crash because the measurements were not very similar. For example, one measurements were not very similar. For example, one measurement for the rubber was 65 cm, and another one was measurement for the rubber was 65 cm, and another one was 27.5 cm. With no bumper, the car did the worst because the 27.5 cm. With no bumper, the car did the worst because the average distance traveled by the block was 47.4 cm. average distance traveled by the block was 47.4 cm.

ConclusionConclusion There are some things that might have affected the results: the There are some things that might have affected the results: the

car might not have been in the same exact space when I let it go, car might not have been in the same exact space when I let it go, the ramp might have not been in the same exact position for each the ramp might have not been in the same exact position for each trial, the block might not have been in the same place in the car, trial, the block might not have been in the same place in the car, and the barrier might have been a bit loose some of the time. To and the barrier might have been a bit loose some of the time. To make my experiment better, I could have used very strong glue to make my experiment better, I could have used very strong glue to glue the barrier to the ramp. Another thing that I could have done glue the barrier to the ramp. Another thing that I could have done would have been to mark the place to put the block of wood on the would have been to mark the place to put the block of wood on the car.car.

If I wanted to learn more about bumpers, I could try even more If I wanted to learn more about bumpers, I could try even more bumper materials such as goo (in a plastic bag), a sponge, bumper materials such as goo (in a plastic bag), a sponge, aluminum foil, carpet padding, and a spring. If I wanted to learn aluminum foil, carpet padding, and a spring. If I wanted to learn more about car safety in general, I could try and experiment with more about car safety in general, I could try and experiment with different types of air bags and see how badly a clay figure gets different types of air bags and see how badly a clay figure gets beat up, though I would have to try some kind of measurement for beat up, though I would have to try some kind of measurement for it.it.

Photos of the InvestigationPhotos of the Investigation

Bumper carsBumper cars

The End

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