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At a picnic on a hill, a boy falls over ...

At a picnic on a hill, a boy falls over the cliff. Suddenly Shaktiman arrives and dives off the edge `2.0s` after the starts of the boyd's fall. If the cliff is `100m` high, what must Shaktiman's initial velocity be if he is to catch the boy just before he reaches the ground ?

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Verified by Experts

The correct Answer is:
`27.3 m//s`

`100 = (1)/(2) g T^(2)`
`T = sqrt(20) sec`
`100 = v sqrt(20) + (1)/(2) xx g (sqrt(20))^(2)`
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