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Question
A ball falls to the ground as shown below :
What is the potential energy of ball at B?
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Solution
Total energy of a free falling object remains conserved.
So,
Total energy at A = Total energy at B
So,
(K.E)A + (P.E)A = (K.E)B + (P.E)B
Thus
Total energy at A = (K.E)B + (P.E)B
Therefore,
(P.E)B = (80 – 48) J= 32 J
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