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A dics is rotating in a room. A boy standing near the rim of the disc of radius `R` finds the water droplet falling from the ceiling is always falling on his head. As one drop hits his head, other one starts from the ceiling. If height of the roof above his head is `H` , then angular velocity of the disc is

A

`pi sqrt((2gR)/(H^(2)))`

B

`pi sqrt((2gH)/(R^(2)))`

C

`pi sqrt((2g)/(H))`

D

`pi sqrt((2g)/(R ))`

Text Solution

Verified by Experts

The correct Answer is:
C
A disc of ………..
Time taken by the drop to hit is `T = sqrt((2H)/(g))`
Now the angular velocity `omega = (2pi)/(T) = pi sqrt((2g)/(H))` .
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