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A constant external torque tau acts for ...

A constant external torque `tau` acts for a very brief period `/_\t` on a rotating system having moment of inertia `I` then

A

The angular momentum of the system will change by `tau Delta t`

B

The angular velocity of the system will change by `(tau Delta t)/I`

C

If the system was intially at rest, it will acquire rotational kinetic anergy `(tau Delta t)^(2)/(2I)`

D

The kinetic energy of the system will change by `(tau Delta t)^(2)/I`

Text Solution

Verified by Experts

The correct Answer is:
A, B, C

`Iomega=tauDeltat`
hence `1/2Iomega^(2)=(tauDeltat)^(2)/(2I)`
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