A stone is dropped from a certain height which can reach the ground in `5 s`. It is stopped after `3 s` of its fall and then it is again released. The total time taken by the stone to reach the ground will be .A. (a) `2 s`B. (b) 3 s`C. ( ` 4s`D. (d)` none of these`.

A stone is dropped from a certain height which can reach the ground in

1.	A stone is dropped from a certain height which can reach the ground in `5 s`. It is stopped after `3 s` of its fall and then it is again released. The total time taken by the stone to reach the ground will be .A. (a) `2 s`B. (b) 3 s`C. ( ` 4s`D. (d)` none of these`.
Answer» Correct Answer - C Height from where the stoneis dropped = 1/2 gt^2` ` = 1/2 xx 9.8 8 xx 5%2 = 4.9 xx 9 m` Vertoca, dpwmward dostamce covered by stone in `3` seconds ` 1/2 xx 9.0 xx 3^2 = 4.9 xx 9 m` Velocity attained `= 9.8 xx 3 ms^(-1)` Remaining distance ` 4.9 xx 25-4.9 xx 9` `= 4.9 xx 16 m` If ` t_1` is the tiem taken to cover the remaining distance when stone is dropped again (u=0)` ` 4.9 xx 16 1/2 xx 9.8 t^2` ` t= sqrty16 = 4 s`.

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A stone is dropped from a certain height which can reach the ground in `5 s`. It is stopped after `3 s` of its fall and then it is again released. The total time taken by the stone to reach the ground will be .A. (a) `2 s`B. (b) 3 s`C. ( ` 4s`D. (d)` none of these`.

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