How does the force of impact change as speed increases?

Answer: D — It increases as a square of the speed

The force of impact is directly related to the speed of a vehicle due to the principles of physics, particularly Newton's laws of motion. As speed increases, the kinetic energy of the vehicle increases, which is a function of the square of the speed. This means that if you double the speed of a vehicle, the kinetic energy—and thus the potential force of impact—quadruples. The formula for kinetic energy is given by \( KE = \frac{1}{2} mv^2 \), where \( m \) is the mass of the object and \( v \) is its velocity. From this relationship, it becomes clear that any increase in speed does not simply lead to a direct increase in force but rather a much larger increase due to the squaring of speed. Therefore, as the vehicle's speed increases, the impact force will increase exponentially, specifically as a square of the speed, leading to significantly higher forces during collisions at higher speeds.