# Car Accidents and Physics

2070 Words Jun 15th, 2007 9 Pages
Every day, many Americans are hurt or killed in car accidents. Many factors can play into an accident. Road condition, mechanical failure, driver error, or simply an 'act of God'? Despite the countless reasons for a car accident, one factor is always present, no matter what the case: physics. Every accident that has ever occurred has involved physics. Using references found in the class text, in science journals, and on the Internet, I will prove this to you. Take, for example, two cars traveling in opposite directions at 100km/h. One of the drivers dozes off and crosses over the centerline. The two cars hit head on. The driver of car A has remained inside the car and has broken ribs. The driver of car B, however, is on the hood of …show more content…
This is a lot of force for one person. So I wonder how those parents with the unbuckled children in the front seat expect to hold back a child exerting 172.4 kg of force while they are trying to hold themselves from crashing into the windshield with 949.5 kg of force. Newton's Third Law of Motion states that "for every action there is an equal and opposite reaction force" (Hewitt, 71). This law helps explain why a collision at low speed is less serious than one at high speeds. If a car exerts a small force on a brick wall due to low speed then the car and its passengers will experience a force of equal magnitude, but in the opposite direction. If cars of unequal mass collide the more massive car will force the smaller vehicle backwards and the smaller car will experience more force. This is due to the conservation of momentum. The Law of Conservation of Momentum states that in an isolated system the momentum before a collision is equal to the momentum after the collision, if we disregard friction (Hewitt 92, 93). So in the example above we can see that the smaller car gained the momentum lost by the larger car. If two cars of equal mass collide and all the potential energy is converted back into kinetic energy after the collision then the collision is said to be elastic. However if the two