Question

In which situation is no work being done?

Answer 1

A and B
work = displacement*force
work is said to be done only when the force applied on the body makes the body move.
if force or displacement is zero than no work is being done
therefore in cases A and B no work is done

Answer 2

Answer:

Work is said to occur when a force is able to cause displacement of an object in the direction of the applied force. It is given by the scalar product of force and displacement.

W = F.s = F s cos θ

Thus, no work is being done when no force is applied ( ∵ F = 0, W = 0) or the force does not result into displacement (∵ s = 0, F = 0) or when the force and displacement are perpendicular to each other (∵ θ =0, cos θ =0, W =0).