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प्रश्न
A ball is thrown up with a speed of 4.9 ms-1.
Calculate the maximum height it would gain before it begins to fall.
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उत्तर
Initial speed of ball is = 4.9 ms-1.
Acceleration due to gravity = -9.8 ms-2.
We know v2 - u2 =2as
At highest point final velocity is zero so
0 - 4.9 X 4.9 = 2 X (-9.8) S
S = 1.125 m
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