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प्रश्न
A ball is thrown up with a speed of 4.9 ms-1.
Calculate the time it takes to reach this height.
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उत्तर
Initial speed of ball is = 4.9 ms-1.
Acceleration due to gravity = -9.8 ms-2.
We know v = u + at
0 = 4.9 - 9.8 t
T = 0.5 sec.
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