A car is able to stop in a distance d.Assuming the same braking force (and therefore the same acceleration),what distance does this car require to stop when it is traveling twice as fast?
A)d
B)2d
C) d
D)4d
E)2 d

Question

A car is able to stop in a distance d.Assuming the same braking force (and therefore the same acceleration),what distance does this car require to stop when it is traveling twice as fast?
A)d 
B)2d 
C) d 
D)4d 
E)2 d

Quizplus · Accepted Answer

The distance required to stop a car is proportional to the square of its initial velocity. This means that if the velocity is doubled, the stopping distance will be four times as much. Therefore, the car traveling twice as fast will require four times the stopping distance (d x 4 = 4d). The correct choice is D.

A Car Is Able to Stop in a Distance D