The laws of physics determine that the force of impact increases with the square of the increase in speed. So, if you double the speed of a car, you increase its force of impact four times. If you triple the speed, the impact is nine times as great.
Observe that the greater the time over which the collision occurs, the smaller the force acting upon the object. Thus, to minimize the effect of the force on an object involved in a collision, the time must be increased.
