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Question
A body of mass m falls from a height h1 to a height h2, above the ground (h1 > h2). What is the loss of potential energy?
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Solution
At height h1, initial potential energy of body = mgh1
At height h2, final potential energy of body = mgh2
Loss in potential energy = Initial potential energy − Final potential energy
= (mgh1 − mgh2)
= mg (h1 − h2)
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