[填空题]
A centrifuge rotor ro*t*kfm-lnlg di,4 5cvtating at 10,300 rpm1:x7wc aopkc 4 is shut off and is eventually brought uniformly t:7xwokpc4 ac1 o 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