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A body of mass 1 kg falls to the ground ...

A body of mass 1 kg falls to the ground from the roof of a building 20 m high. Find its
(ii) velocity when it reaches the ground,

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Verified by Experts

Suppose the body touches the ground with velocity v.
Potential energy at roof level = kinetic energy just before touching the ground.
`therefore 196 =1/2 xx1 xxv^2`
`therefore v^2 =392 and v=19.8 m*s^(-1)`
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