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CBSE Class 9 Answered

A ball is dropped from a height of 49m. Find the time interval in which the ball hits the ground (g=9.8/s square)
Asked by adItTYAGuPtaiLt | 21 Jun, 2018, 07:21: PM
answered-by-expert Expert Answer
Formula to be used, " S = u×t+(1/2)×a×t2 " , with initial velocity u = 0.
 
49 = (1/2)×9.8×t2 ; solving for t, we get t =√10 s = 3.16 s
 
Answered by Thiyagarajan K | 21 Jun, 2018, 08:22: PM

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CBSE 9 - Physics
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