[填空题]
A centrifuge rotor rotathy9+ b;x)af kz b /e,2:js ; ;cye7tyqgfn+iqxing at 10,300 rpm is shut off and is eventually brought uniformly to rest by a frictional torque g7yq;xt ycs: 2i/b+,fneq ; ejof 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