QUESTION: How does the steepness of a slope and mass affect a collision's outcome?
During the investigation two different height levels were set to replicate the steepness of two roadways. The roadways were created using two different size binders, a one and a half inch and a three inch. At its highest point the one and a half inch binder was 5 centimeters off the ground while the three inch binder was 10 centimeters off the ground. Both binders were set flat on the same surface side by side to eliminate any discrepancy based on placement. There were two toy vehicles used to represent vehicles in a collision, one was an SUV and the other a sports car. First the toy car was sent down the slope into the SUV to see what would happen during a collision and then the vehicles were switched and the heavier SUV was sent down the slope into the sports car. While both vehicles had an impact on each other there were certain factors that could not be overlooked and the results were a mixture of what was expected as well as a few surprising facts as well.
Firstly, the smaller slope created less of an impact during the collision and thus less damage overall to either vehicle. The SUV was able to push the sports car back and over quite easily due to its greater overall mass and the momentum it had coming off the slope. When the vehicles were switched around the sports car was able to push the SUV off the ramp and on one try it even managed to cause the SUV to roll over. When the larger binder was used as the slope the effects of the steepness of the slope was even more evident. The SUV completely knocked the car off the ramp every time and the car was spun around and even flipped on one occasion. Quite surprisingly, when the vehicles were switched the sports car was able to also knock the SUV off the ramp and flip it as well. While both vehicles were able to move each other it was obvious that the vehicle with the larger mass had an overall advantage over the smaller vehicle. However, it should be noted that there are factors that affect the outcome of any collision involving two vehicles.
A truck going down a slope and hitting a car will have a greater effect than an SUV or a car doing the same exact act. What was evidenced during this investigation was that the sports car was able to flip the SUV over when it was wound up and the momentum increased exponentially, which points to the fact that a smaller, lighter vehicle traveling downhill at a greater speed than a relatively larger one can have an adverse effect on the larger vehicle. It should also be noted that the effect of the collision on the vehicles also depends on whether or not the vehicle at the bottom of the slope is moving or standing still. Also a vehicle moving towards the vehicle coming down the slope creates an opposite force that can cause both vehicles to flip or spin wildly out of control.
It would be the perfect activity for the eighth graders within my classroom whom I hope would gain a greater understanding of mass, momentum, and incline in the scientific sense but also be able to relate it to their lives in the real world as well. To make it more exciting for my students I could actually take them outside to the side of the school which has an incline. I could have the students decide how to create the level steepness that they want by adding to that incline and have them utilize radio controlled vehicles of different sizes as well as the standard manual ones to determine the effect of lessening and/or increasing momentum and velocity.
As far as my own investigation went, I think it would have been great if both vehicles were able to be wound up instead of just the sports car. Also, it would have been a more true representation of the difference in mass I think if the SUV was a bit heavier than it actually is.
