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Question
In loading a truck, a man lifts boxes of 100 N each through a height of 1.5 m.
How much work does he do in lifting one box?
Solution
Weight of box, (W) = 100 N
Height, (h) = 1.5 m
Acceleration due to gravity, (g) = 10 m/s2
(a) We can calculate the work done against gravity as,
Work done = (Weight of body) × (Vertical distance)
= (100) × (1.5) J
= 150 J
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