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Question
How much energy is gained by a box of mass 20 kg when a man, raises the box by 0.5 m in order to place it inside the bus? (g=10 m/s-2)
Solution
Height to which the box is raised h = 0.5 m
∴ Energy gained = mgh
= 20 × 10 × 0.5 m
= 100 J
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