Bumper Cars By Shea

Question How do different kinds of bumper materials affect how much energy is transferred to the “passenger” in a car collision?

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

Materials  rectangular wood block (16.9 grams)  Pasco GO car (229 grams)  metal ramp  support for ramp  2-cm high barrier to put at the end of ramp  meter stick  bumper materials: foam packing peanuts, bubble wrap, half of a rubber ball

Procedure Do this procedure for each type of bumper material (no bumper, foam, bubble wrap, rubber): PPPPut wooden block on the car. PPPPut car on the top of a ramp that has been raised 15 cm off the ground. The ramp should have a 2 cm high barrier at the bottom to stop the car. LLLLet the car go without pushing it. MMMMeasure the distance the center of the block goes after the car hits the barrier. RRRRecord data. RRRRepeat steps 1-5 four more times.

Variables Independent variable:  The type of bumper material Dependent variable:  How far the block of wood (“passenger”) goes after the collision Controlled variables:  Same car  Same length and angle of track  Same block of wood  Same starting position and speed of cart  Same position of barrier

Data Chart No BumperFoamBubble WrapRubber Trial cm30.5 cm36 cm36.5 cm Trial cm48.5 cm35 cm65 cm Trial cm39 cm35.5 cm47.5 cm Trial 454 cm31 cm48.5 cm27.5 cm Trial cm37 cm47.5 cm37.5 cm Average47.4 cm37.2 cm40.5 cm42.8 cm

Graph

Written Explanation The data shows that the average distance the block 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, and for the rubber bumper it is 42.8 cm. The data shows that the average distance the block 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, and for the rubber bumper it is 42.8 cm. The foam and bubble wrap kept the most amount of energy from being transferred to the “passenger” (the block), but the foam made it (on average) go 3.3 cm less than the bubble wrap – which means that foam is the best bumper material because it causes the least amount of energy to be transferred to the “passenger”. The foam and bubble wrap kept the most amount of energy from being transferred to the “passenger” (the block), but the foam made it (on average) go 3.3 cm less than the bubble wrap – which means that foam is the best bumper material because it causes the least amount of energy to be transferred to the “passenger”.

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

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

Conclusion 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, 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, 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 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 car. If I wanted to learn more about bumpers, I could try even more bumper materials such as goo (in a plastic bag), a sponge, aluminum foil, carpet padding, and a spring. If I wanted to learn 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 beat up, though I would have to try some kind of measurement for it.

Photos of the Investigation

Bumper cars The End Hope you enjoyed the presentation !