Physics
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
Work, Energy & Power
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Answer
Given,
mass = 200kgf
height = 2.5m
time = 5s
Force = mg
= 200 x 10 = 2000N
So, we get force is equal to 2000N
(i) Work done = F x h
Therefore, work done is 5000 J.
(ii)
Therefore, power developed by the boy 1000 W.
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