Question
A porter lifts luggage of 20 kg from the ground and puts it on his head 2 m above the ground. Calculate the work done by him on the luggage (take g = 10ms-2)
Solution
Mass of the luggage (m)= 20 kg ⇒ Height above the ground (h) = 2m So, the work done by porter on luggage is ⇒ P.E = mgh = (20)×(10)×(2) = 400 J
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