h how many revolutions will the rotor turn before coming to rest?

A centrifuge rotor rotating at 14,000 rpm is shut off and is eventually brought uniformly to rest by a frictional torque of 1.60 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?