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A circular ring of mass m and radius r i...

A circular ring of mass m and radius r is rotating in a horizontal plane about an axis vertical to its plane. What will its rotational kinetic energy? (Angular speed of ring is w)

A

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

B

`mr^(2)w^(2)`

C

`(1)/(2)mrw^(2)`

D

`mrw^(2)`

Text Solution

Verified by Experts

The correct Answer is:
A
Rotational kinetic energy = `(1)/(2)Iomega^(2)` but for ring
`I=mr^(2)`
`=(1)/(2)mr^(2)omega^(2)`
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