[填空题]
A centrifuge rotor rota8o2urfi jb36ating at 10,300 rpm is shut off and is event5k; l.,bpwqsr (ba b( a)gq1lvually brought uniformly to rest by a frictional torque of 1.2 b5 alvb,a1)ws qp (lb q;(r.gk$m \cdot N$ 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