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CBSE Class 9 Answered

A ball is thrown with a speed of 0.5m/s.(I) how high will it go before it begins to fall? (2)how long will it take to reach that height ?
Asked by Vikas | 03 Nov, 2018, 01:26: PM
answered-by-expert Expert Answer
Time to reach maximum hight is obtained using the formula, v2 = u2 -2gh ................(1)
where v is final speed which is zero at maximum height h, u is initial speed and g is acceleration due to gravity.
 
hence from eqn.(1),  h = u2 /(2g)  = (0.5×0.5) / (2×9.8) = .013 m = 13 cm
 
time t to reach maximum height h is obtained using the formula v = u - g×t  or   t = u/g = 0.5/9.8 ≈ .05 s
Answered by Thiyagarajan K | 03 Nov, 2018, 10:12: PM

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