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)

Answer 1

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.