A particle is dropped under gravity from rest from a height $h{\,}(g = 9.8\,m/{\sec ^2})$ and it travels a distance $9h/25$ in the last second, the height $h$ is......... $m$
A particle is dropped under gravity from rest from a height $h{\,}(g = 9.8\,m/{\sec ^2})$ and it travels a distance $9h/25$ in the last second, the height $h$ is......... $m$
$100 $
$122.5$
$145$
$167.5 $
A particle is dropped under gravity from rest from a height $h{\,}(g = 9.8\,m/{\sec ^2})$ and it travels a distance $9h/25$ in the last second, the height $h$ is......... $m$
Let $h$ distance is covered in $n$ sec
$ \Rightarrow h = \frac{1}{2}g{n^2}$…(i)
Distance covered in ${n^{th}}$sec$ = \frac{1}{2}g(2n - 1)$
$ \Rightarrow \frac{{9h}}{{25}} = \frac{g}{2}(2n - 1)$…(ii)
From $(i)$ and $(ii)$,
$h = 122.5\;m$
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