A man throws balls with the same speed vertically upwards one after the other at an interval of 2 second. What should be the speed of the throw so that two balls are in the sky at any time?

A man throws balls with the same speed vertically upwards one after th

1.	A man throws balls with the same speed vertically upwards one after the other at an interval of 2 second. What should be the speed of the throw so that two balls are in the sky at any time?
Answer» At least 9.8 `m//s` Any speed less than `19.6m//s` Only with speed `19.6 m//s` More than `19.6 m//s` SOLUTION :For more than 2 BALLS to be in the air, the time interval should be t>(2+2)s or 4 s. The maximum time of flight for each ball is `=(2u)/(g)` THUS `(2u)/(g)` >4 s or U > 2g Bur g=9.8 `ms^(-2)` `:. ` u> 19.6 `ms^(-1)`

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A man throws balls with the same speed vertically upwards one after the other at an interval of 2 second. What should be the speed of the throw so that two balls are in the sky at any time?

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