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प्रश्न
A box of weight 150 kgf has gravitational potential energy stored in it equal to 14700 J. Find the height of the box above the ground. (Take g = 9.8 N kg-1)
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उत्तर
Gravitational potential energy = 14700 J
Force of gravity = mg = 150 × 9.8N/kg = 1470N
Gravitational potential energy = mgh
14700 =1470 x h
h =10m
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