Q. A fly wheel rotates about an axis. Due to friction at the axis, it experiences angular retardation proportional to its angular velocity. If its angular velocity falls to half the value while it makes revolutions, how many more revolutions will it make before coming to rest ?

System of Particles and Rotational Motion Report Error

A

B

C

D

Solution:

Given that

On integrating we get

Initially

After revolution,

For final stop,

i.e. revolution,
Number of revolutions that will further occur before flywheel stops

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