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Question
In loading a truck, a man lifts boxes of 100 N each through a height of 1.5 m.
If the man lifts 4 boxes per minute, at what power is he working?
(g = 10 m s−2)
Solution
Work done in lifting 4 boxes,
Work done
= (150) × (4) J
= 600 J
Time taken, (t) = 60 s
Now, we can calculate the power as,
Power = `"Work done"/"Time"`
So ,
Power = `600/60` W
= 10 W
So, the power is 10 W.
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