[填空题]
A centrifuge rotor rotating gpu9yxyk; n5la z;y5gu95 c7x at 10,300 rpm is shut of9t tid0dbzv /5f and is eventually brought uniformly z05 tditv/db9 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