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प्रश्न
A body of mass 5 kg falls from a height of 10 m to 4 m. Calculate:
The loss in potential energy of the body,
उत्तर
Mass of the body = 5 kg
P.E. at height 10m = mgh = 5 × 10 × 10 = 500 J
P.E. at height 4 m = mgh = 5 × 10 × 4 = 200 J
Loss in P.E. = (500 – 200) J = 300 J
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