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Question
A weightlifter is lifting weights of mass 200 kg up to a height of 2 metres. If g = 9.8 m s−2, calculate :
potential energy acquired by the weights.
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Solution
Mass of the weights, (m) = 200 kg
Acceleration due to gravity, (g) = 9.8 m/s2
Height above the ground, (h) = 2 m
We can calculate potential energy as,
F.E = m × g × h
So,
`P.E = 200 xx 9.8 xx 2 "J"`
= 3920 J
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