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Question
Find the gravitational potential energy of 2.5 kg mass kept at a height of 15 m above the ground. The force of gravity on mass 1 kg is 10 n.
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Solution
Mass m = 2.5 kg
Gravitational potential energy is the work done against the force of gravity ¡s stored in the body at a height h.
P.E = U = mgh
U = 2.5 × 10 × 15
U = 25/10 × 10 × 15 = 375 J
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