We have h=21gt22 and h+400=21g(t+4)2. Subtracting we get 400=8 g+4gt ⇒t=8sec∴h=21×10×64=320 m∴ Desired height =320+400=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/s2, then the height above the point P from where the body began to fall is
Held on 30 Apr 2006 · Verified 6 Jul 2026.
720 m
900 m
320 m
680 m
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