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Question
A load of 100 kg is pulled up by 5 m. Calculate the work done. (g = 9.8 m/s2)
Solution
Mass of the body (m) = 100 kg
Height by which the body is lifted (h) = 5 m
Work done in lifting a body = (Weight of body) (Vertical distance)
So, W = (m) (g) (h)
Therefore,
(W) = (100) (9.8) (5) J .
= 4900 J
So , the work done is 4900 J .
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