A centrifuge rotor rotating at 13,000 rpm is shut off and is eventually brought uniformly to rest by a frictional torque of 1.30 m·N. If the mass of the rotor is 4.80 kg and it can be approximated as a solid cylinder of radius 0.0710 m, through how many revolutions will the rotor turn before coming to rest?

Answer 1

calculate the moment of inertia I for a solid cylinder.
Torque= I * alpha
then

displcement= wi*t-1/2 alpha*t^2

you are given wi, t, and have calculated alpha