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Question
A body of mass 5 kg falls from a height of 10 m to 4 m. Calculate:
The total energy possessed by the body at any instant? (Take g = 10 ms-2).
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Solution
The total energy possessed by the body at
any instant remains constant for free-fall
It is equal to the sum of P.E. and K.E
∴ At height 10 m , i.e. at top most point K.E = 0
∴ Total energy = P.E. + K.E.
Total energy = 500 + 0 = 500 J
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