[填空题]
A centrifuge rotor rotating at 10,b tb61 do,ef.t+vk+ lz300 rpm is shut off and is eventua; xue4hv6 3rhally brought uniformly to rest by a frictional tore ru64hxa hv3;que of 1.2 $m \cdot N$ 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, $rev$ how long will it take? s