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A child drop a ball from a window, the ball strike the ground in 3 s. what is the velocity of the ball before it hit the ground
Asked by Nimmi | 09 Jun, 2018, 03:14: PM
answered-by-expert Expert Answer
If the dropped ball strikes the ground after 3 s, then vertical distance S travelled by the ball is given by
 
S = (1/2)×g×t2 = (1/2)×9.8×3×3 = 44.1 m
 
velocity V before hit the ground is obtained from :- v2 = 2×g×S = 2×9.8×44.1 = 864.36
hence v = 29.4 m/s
 
Answered by Thiyagarajan K | 09 Jun, 2018, 05:20: PM

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CBSE 9 - Physics
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