Car A is traveling at twice the speed of car B.They both hit the brakes at the same time and decrease their velocities at the same rate.If car B travels a distance D before stopping,how far does car A travel before stopping?
A)4D
B)2D
C)D
D)D/2
E)D/4

Question

Quizplus · Accepted Answer

The distance traveled before stopping when decelerating at a constant rate is proportional to the square of the initial velocity. Since car A is traveling at twice the speed of car B, it will travel $2^2 = 4$ times the distance before stopping, hence 4D.

Car a Is Traveling at Twice the Speed of Car