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प्रश्न
A weight lifted a load of 200 kgf to a height of 2.5 m in 5 s. calculate: (i) the work done, and (ii) the power developed by him. Take g= 10 N kg-1.
उत्तर
Given load m = 200kgf, displacement h = 25 m, time = 5s, g = 10 N kg-1
Now work done = 200 kgf x 25 = 50000 J
or power = `"work done"/"time taken" = 5000/5` = 1000 watt
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