Question

A boy of mass m climbs up a stairs of vertical height h.
(a) What is the work done by the boy against the force of gravity?
(b) What would have been the work done if he uses a lift in climbing the same vertical height?

April 8, 2024

Answer

When a boy of mass m climb up stairs of vertical height h then

(a) Work done by the boy against the force of gravity is

W = FS = mgh

(b) The work done when the boy uses a lift in climbing the same vertical height

W = FS = mgh

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