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A man throws balls with the same speed v...

A man throws balls with the same speed vertically upwards one after another at an interval of 2 seconds. What should be the speed so that more than two balls are in the sky at any time? ( g = `9.8ms^-2` )

A

more than 19.6 `ms^-1`

B

at least 9.8 `ms^-1`

C

any speed less than 19.6 `ms^-1`

D

only speed 19.6 `ms^-1`

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The correct Answer is:
B
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BINA LIBRARY-KINEMATICS - 1-EXERCISE
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  4. Speeds of two identical cars are v and 4v at a specific instant. The r...

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  5. The speed of a boat is 5 km/h in still-water. It crosses a river of wi...

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  6. Thief's car is moving with a speed of 10m/s. A police van chasing the ...

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  7. A particle is moving with a velocity 5m/s towards east and its velocit...

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  8. A body falling from a height travels 40 m in the last 2s of its fall t...

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  9. A stone dropped into a lake form a tower 500 m high. The sound of spla...

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  11. If X = at + bt^2 , where X is distance travelled by a body in km while...

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  13. A body starts from rest. The ratio of the distances travelled by it du...

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  14. A body is released from a height and falls freely. Another body is rel...

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  15. A body dropped from a height h with an initial speed zero reaches the ...

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  16. Water drops fall at regular intervals from a tap, which is 5 m above t...

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  17. A train 150 m in length is moving north at a speed of 10m/s. A parrot ...

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  18. For a body moving along a straight line, the average velocity is equal...

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