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Question
A person of mass 50 kg climbs a tower of height 72 metres. Calculate the work done. (g = 9.8 m s−2).
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Solution
Mass of the body, (m) = 50 kg
Height above the ground, (h) = 72 m
Acceleration due to gravity, (g) = 9.8 m/s2
We can calculate the work done against gravity as,
Work done in lifting a body = Weight of body × Vertical distance
So,
W = m × g × h
So work done,
W = 50 × 9.8 × 72 J
= 35280 J
So, the work done by the man is 35280 J.
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