Weight of boy, m = 50kg
Height, h = 100m
Since the boy does not move anything with his force, therefore, the work done by him is zero.
Work done on the boy = Gain in potential energy.
Potential Energy (P.E) = mgh
⇒50 * 9.8 * 100
Gained potential energy (P.E) by the boy is 49 KJ.
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