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CBSE Class 9 Answered

A player throws a ball vertically upwards. The ball attains height of 25m and then returns back. Find the initial speed of the ball? 
Asked by Vikas | 03 Nov, 2018, 01:23: PM
answered-by-expert Expert Answer
If a ball is thrown vertically, then initial spped of the ball is obtained from the known maximum height h
using the formula " v2 = u2 - 2gh ", where v and u are final and initial speed respectively.
 
At maximum height, final spped is zero.
 
Hence we get , begin mathsize 12px style u space equals space square root of 2 g h space end root equals space square root of 2 cross times 9.8 cross times 25 end root space equals space 22.14 space m end style
Answered by Thiyagarajan K | 03 Nov, 2018, 10:25: PM

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CBSE 9 - Physics
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