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A rectangle solid box of length 0.3m is ...

A rectangle solid box of length `0.3m` is held horizontally , with one of its sides on the edge of a platform of height `5m` . When released , it slip off the table in a very short time `T=0.01` s, remaining essentially horizontal . The angle by which it would rotate when it hits the ground will be `("in radian")` close to:

A

`0.3`

B

`0.02`

C

`0.5`

D

`0.28`

Text Solution

Verified by Experts

The correct Answer is:
C

We consider rod will rotate with respect to point A for time interval `0.01` second, angular velocity w.r.t. A equal to
`alpha=(tau)/(I)=(mg.(L)/(2))/(mL^(2)//3)=(3g)/(2L)`
Angular velocity at `t=0.01` second is,
`omega=alphat=(3g)/(2L)xx0.01=(1)/(2)rad//sec`
Time of light `T=sqrt((2h)/(g))=1sec`
Angle `theta=omegaT=(1)/(2)rad`
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