Question

A weight lifter 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 = 10Nkg^-1

April 8, 2024

Answer

mass = 200 kgf

height = 2.5 m

time = 5 s

Force = mg = 200 × 10 = 2000N

(i) Work done = F × h = 2000 × 2.5 = 5000 J

Therefore, work done is 5000 J.

(ii) Power = $5000\over 5$ = 1000 W

Therefore, power developed by the boy 1000 W.

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