Question

In order for work to be done, what must happen?

A. The object must have potential energy, but it does not need to move.
B. The mass of the object must be too great for the force to be able to move it.
C. The force must move the object a distance.
D. The weight of the object must be too heavy for an opposing force to move it.

Answer 1

Work is done when a force moves an object a distance, specifically in the direction of the force applied.

Step-by-step explanation:

In order for work to be done, C. The force must move the object a distance in the direction of the force. Simply having potential energy or being heavy is not sufficient for work to be performed. Work involves both the application of a force and the movement of an object due to that force. For example, lifting a rock off the ground constitutes work because the rock is displaced in the direction of the applied force, thereby increasing the rock's gravitational potential energy. Holding a briefcase stationary, however, involves no work on the briefcase-Earth system since there is no displacement (movement).