[填空题]
A centrifuge rotor rotatinl.h :k9 by1o2usq/g; o4edm1z8kzvs9 swr4c yg at 10,300 rpm is shut off and is eventually4,7 ,yc t;zc(e djsfqb brought uniformly to rest by a frictional t; 4tfqces cyd, (,zjb7orque 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