[填空题]
A centrifuge rotor rotating at b;eb:iufq-/a*oab3+x3b dpt 10,300 rpm *55ytu0 n7mp ydwjf.ris shut off and is eventually brought uniformly to rest by a frictional torque of 1.2 tf50j nur*ydm.7 5 pyw$m \cdot N$ 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