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Question
A boy of mass m climbs up a staircase of vertical height h.
- What is the work done by the boy against the force of gravity?
- What would have been the work done if he uses a lift in climbing the same vertical height?
Solution
- 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.
- Because displacement occurs in the direction of force, W = mgh in both scenarios.
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