A man in a balloon rising vertically with an acceleration of 4.9m/s2 releases a ball 2 second after the balloon is let go from the ground. The greatest height above the ground reached by the ball is(g=9.8)
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Height travelled by ball (with balloon) in 2 sec h1=12at2=12×4.9×22=9.8m
Velocity of the balloon after 2 sec
Now if the ball is released from the balloon then it acquire same velocity in upward direction.
Let it move up to maximum height h2
Greatest height above the ground reached by the ball = h1+h2=9.8+4.9=14.7m