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A disc of mement of inertia I is rotatin...

A disc of mement of inertia `I` is rotating due to external torque. Its kinetic energy is equal to `Ktheta^(2)`. Where K is the positive constant. Its angular acceleration at an angle `theta` will be:

A

`(k)/(2I)theta`

B

`(k)/(I) theta`

C

`(k)/(4I) theta`

D

`(2k)/(I) theta`

Text Solution

Verified by Experts

The correct Answer is:
D
`1/2 I omega^(2)=K theta^(2) rArr 1/2 I xx 2 cancel(omega) xx (d omega)/(dt)=Kxx 2 theta .cancel((d theta)/(dt)) :.alpha= ( d omega)/(dt)=(2k theta)/(I)`
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