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प्रश्न
Calculate the height through which a body of mass 0.5 kg is lifted if the energy spent in doing so is 1.0 J. Take g = 10 m s-2.
उत्तर
Mass = 0.5 kg
Energy = 1 J
Gravitational potential energy = mgh
⇒ 1 = 0.5 × 10 × h
⇒ 1 = 5h
⇒ `1/5` = h
Height, h = 0.2 m
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