A body falling from rest under gravity passes a certain point P . It was at a distance of 400 m from P , 4 s p

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A body falling from rest under gravity passes a certain point P . It was at a distance of 400 m from P , 4 s prior to passing through P . If g = 10 m/s^2 , then the height above the point P from where the body began to fall is:

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![image](https://pub-7faa453bd1ec4bf0a04cc031c6f058de.r2.dev/images/50501ee6-a27f-473a-b899-b786156b8c0b.png) Let the body fall from point O . Let OP = H .Let the time to reach P be t . H = 1/2gt^2 The body was 400 m above P at time t - 4 .So, the distance fallen in t - 4 seconds is H - 400 . H - 400 = 1/2g(t - 4)^2 Substituting H : 1/2gt^2 - 400 = 1/2g(t^2 - 8t + 16) -400 = 1/2g(-8t + 16) -400 = 5(-8t + 16) -80 = -8t + 16 8t = 96 t = 12 s Height H = 1/2 × 10 × 12^2 = 5 × 144 = 720 m .

A body falling from rest under gravity passes a certain point $P$ . It was at a distance of $400 m$ from $P$ , $4 s$ prior to passing through $P$ . If $g = 10 m/s^{2}$ , then the height above the point $P$ from where the body began to fall is:

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A body falling from rest under gravity passes a certain point P. It was at a distance of 400m from P, 4s prior to passing through P. If g=10m/s2, then the height above the point P from where the body began to fall is: