Two balls are projected simultaneously with the same speed from the top of a tower, one vertically upwards and the other vertically downwards. They reach the ground in 9 second and 4 second respectively. The height of the tower is:

Two balls are projected simultaneously with the same speed from the to

1.	Two balls are projected simultaneously with the same speed from the top of a tower, one vertically upwards and the other vertically downwards. They reach the ground in 9 second and 4 second respectively. The height of the tower is:
Answer» 100 m 120 m 180 m 200 m Solution :Here `h=9(-V)+(1)/(2)xx10xx81` `= -9v+405` ALSO `h=4v+(1)/(2)xx10xx64` `=4v+320` Subtracting 13v =325 or v=25 m `s^(-1)` Thus putting in (i) h=180 m.

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Two balls are projected simultaneously with the same speed from the top of a tower, one vertically upwards and the other vertically downwards. They reach the ground in 9 second and 4 second respectively. The height of the tower is:

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