fizzix project!

The crumple zone of a car is its rear end and front end. These areas are designed to crumple, or smash up, upon impact (as opposed to attempting to remain as unchanged as possible). The area in which passengers and the driver sit, however, is a safety zone. It is reinforced with bars strong enough to withstand a crash.

The purpose of the crumple zone is to decrease the force experienced by the occupants of the car during a crash into something immovable, like a brick wall. Crumple zones accomplish this by increasing the time it take the vehicle to stop. A rigid car will stop almost right away, making the “change in time” in the equation below very short. A car that smashes up will take longer to stop, since the car can go farther “into” the wall (or other object) while its front or rear is busy getting smashed up.

Acceleration = change in velocity ÷ change in time

As this equation illustrates, acceleration is large when time change is small, and vice versa. Thus, a car with a crumple zone has a smaller acceleration than one without a crumple zone. The next equation shows that this means the person in the car (and the car itself) will experience a smaller force than if no crumple zone were present.

Force = mass × acceleration

The person in the car has the same velocity and acceleration as the car (even if he or she appears to be sitting still), but the force will be different because mass is taken into account.

Mathematically, if the change in time caused by the crumple zone is, for example, 0.10 seconds instead of 0.01 seconds without a crumple zone, acceleration and force will be one-tenth as great as they would be otherwise! This change could be enough to stop you from going through the windshield, and it could possibly save your life.


Isn't that interesting?