An elevator supported by a single cable descends a shaft at a constant speed. The only forces acting on the elevator are the tension in the cable and the gravitational force. Which one of the following statements is true?
A)The magnitude of the work done by the tension force is larger than that done by the gravitational force.
B)The magnitude of the work done by the gravitational force is larger than that done by the tension force.
C)The work done by the tension force is zero joules.
D)The work done by the gravitational force is zero joules.
E)The net work done by the two forces is zero joules.

Question

Quizplus · Accepted Answer

The elevator moves at a constant speed, meaning there is no net acceleration. Therefore, the net force is zero, and the work done by the tension force is equal in magnitude and opposite in direction to the work done by the gravitational force, resulting in a net work of zero joules.

An Elevator Supported by a Single Cable Descends a Shaft