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प्रश्न
A machine raises a load of 750 N through a height of 16 m in 5s. calculate:
(i) work done by machine,
(ii) power at which the machine works.
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उत्तर
Given, load m = 750 N, displacement h = 16 m, time = 5 s, g = 10 N kg -1
now work done = mgh = 750 x 16 = 12000J
or power = `"work done"/"time taken" = 12000/5` = 2400 watt
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