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A ball is dropped from a building. Heigh...

A ball is dropped from a building. Height of the building is 45 m. The ball moves under the effect of gravity.
How much time will it take to reach the ground?

A

3s

B

6s

C

5s

D

none

Text Solution

Verified by Experts

The correct Answer is:
A
`t = sqrt(2h//g) = sqrt((2 xx 45)/(10)) = sqrt(9) = 3`
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