[填空题]
A centrifuge rotor rk i4); d.evvk+*ite wcotatc;5q:v i iez0 o cyyo7xkg)4h7ing at 10,300 rpm is shut off and is eventually brought unifq5c0:;yh z7)vo4gy e7cixi k oormly to 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
