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A fly wheel is rotating with a kinetic e...

A fly wheel is rotating with a kinetic energy of 200 J. A constant torque of 4 Nm acts on it to oppose its motion. Before coming to rest, the number of revolutions completed by it is

A

`100//pi`

B

`50//pi`

C

`25//pi`

D

`25//pi`

Text Solution

Verified by Experts

The correct Answer is:
C
`KE = tau theta`
`theta = (KE)/(tau)=(200)/(4)=50`
`N = (theta)/(2pi)=(50)/(2pi)=(25)/(pi)`
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