Question

A boy of mass m climbs up a staircase of vertical height h.

1. What is the work done by the boy against the force of gravity?
2. What would have been the work done if he uses a lift in climbing the same vertical height?

Answer 1

1. When a boy with mass m climbs a staircase with a vertical height of h, he works against gravity by using his own weight, F = mg and W = F x h.
2. Because displacement occurs in the direction of force, W = mgh in both scenarios.