[填空题]
A centrifuge rotor rotating at 10,300 rpj2ttj g*-1y (raiys.y b m,t6vm is shut off and is eventually b7qj z0z6; .rejn ns*cg** emymrought uniformly **0y j6jms7* ; emqeg.z nrzcnto rest by a frictional torque 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