- P.E at the surface of bridge = mgh = m× 9.8 × 10 = 98m jouls
P.E when it falls 5 meter = m × 9.8 × 5 = 49m jouls
Difference in P.E = K.E = 98m – 49m = 49m jouls. Therefore,
½ mv2 = 49m OR v2 = 2 × 49 = 98 OR v = √98 = 9.899 = 9.9 ms-1
Therefore, velocity of the body 5 m above the water surface is 9.9 ms-1.
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