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प्रश्न
A weightlifter is lifting weights of mass 200 kg up to a height of 2 metres. If g = 9.8 m s−2, calculate :
work done by the weightlifter
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उत्तर
Potential energy of a body kept at some height is equal to the amount of work done against gravity in moving the body to that position. Therefore, work done by the weight lifter is 3920 J .
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