Which of the following case shows work done is not zero?
Rohan climbs the staircase to go to the second floor.
In physics, the term 'work' is used in relation to the displacement produced by a force. Work done in moving a body is equal to the product of force and displacement of the body in the direction of force. Therefore, when Rohan climbs the staircase to go to the second floor he is doing some work.