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Question
A ball of mass 200 g falls from a height of 5 m. What will be its kinetic energy when it just reaches the ground? (g = 9.8 m s−2)
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Solution
Given, m = 200 g.
h = 5m.
When the ball reaches the ground then P.E. = K.E.
K.E. = mgh =`200/1000xx9.8xx5` = 9.8 Joule
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