Q8 of 23 Page 117

A boy is throwing balls into the air one by one in such a way that when the first ball is thrown reaches maximum height he starts to throw the second ball. He repeats this activity. To what height do the balls rise if he throws twice in a second?

Since the boy is throwing two balls per second

⇒ He is throwing one ball in half a second.


⇒ Ball takes half second to reach the maximum height.


WE know that time taken to reach maximum height =


⇒


⇒


⇒


⇒


Hence initial velocity of ball is 5 ms.


Also the maximum height (H) =


⇒ H =


⇒ H =


⇒ H = 1.25 m


Maximum height reached by the ball is 1.25 m


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