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The angular momentum of a rotating body ...

The angular momentum of a rotating body changes from `A_(0)` to `4 A_(0)` in 4 min. The torque acting on the body is

A

`(3)/(4)A_(0)`

B

`4 A_(0)`

C

`3 A_(0)`

D

`(3)/(2)A_(0)`

Text Solution

Verified by Experts

The correct Answer is:
A

Torque = Rate of change of angular momentum `(tau)=(dL)/(dt)`
Given, `dL=4A_(0)-A_(0)=3A_(0),dt=4 min`
`rArr` Torque acting on the body, `tau=(3)/(4)A_(0)`.
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