Question

a ball dropped from top of a building reachs the bottom in 3.42s what is the height of the building​

Answer 1

Explanation:

HEY MATE ......

$we \: know \: that \: \\ \\ starting \: \: from \: rest \: any \: body \: \\ \\ will \: take \: time \: t \: \\ \\ in \: falling \: height \: given \: by \: t \\ \\ \implies \: \frac{ 2\sqrt{2h} }{g} \\ \\ put \: t \: = 3.42 |sec| \: \\ \\ and \: \\ \\ g \: = 9.8m | {sec}^{2} | \\ \\ we \: get \: h = 0.987(approx)$

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