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A ring of mass m and radius r rotates ab...

A ring of mass m and radius r rotates about an axis passing through its centre and perpendicular to its plane with angular velocity `omega`. Its kinetic energy is

A

`1/2mr^(2)omega^(2)`

B

`mromega^(2)`

C

`mr^(2)omega^(2)`

D

`1/2mromega^(2)`

Text Solution

Verified by Experts

The correct Answer is:
A
Kinetic energy =`1/2Iomega^(2)`, and for ring `I=mr^(2)`. Hence KE `=1/2mr^(2)omega^(2)`
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