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प्रश्न
A weight lifter lifted a load of 200 kgf to a height of 2.5 m in 5 s. Calculate:
- the work done, and
- the power developed by him. Take g = 10 N kg-1
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उत्तर
Force= mg = 200 × 10 = 2000 N
Distance, S = 2.5m
Time , t = 5 s
(i) Work done, W= F × S
W = 2000 × 2.5m = 5000 J
(ii) Power developed = `w/t`= `5000/5` = 1000 W
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