The brakes of a speeding truck are slammed on and it skids to a stop. If the truck were heavily loaded so that it had twice the total mass, the skidding distance would be
A) 1 1/2 times as far.
B) 1/2 as far.
C) 2 times as far.
D) 4 times as far.
E) the same.

Question

Quizplus · Accepted Answer

The skidding distance is independent of the mass of the truck. The frictional force, which causes the truck to stop, is proportional to the normal force (which is the weight of the truck), and since both the frictional force and the inertia (mass) increase proportionally, the skidding distance remains the same.

The Brakes of a Speeding Truck Are Slammed on and It