When the brakes of an automobile are applied, the road exerts the greatest retarding force:
A)while the wheels are sliding
B)just before the wheels start to slide
C)when the automobile is going fastest
D)when the acceleration is least
E)at the instant when the speed begins to change

Question

Quizplus · Accepted Answer

Just before the wheels start to slide, static friction exists between the tires and the road. This provides the greatest retarding force. Once the wheels start to slide, the frictional force decreases, and the retarding force decreases as well.

When the Brakes of an Automobile Are Applied, the Road