[填空题]
A grinding wheel is a uniform cylinde-n u(t iwpn 16q44ml z rj,zo5aqzay60r witn68 :m9afe0ogfp s.esh a radius of 8.50 cm and a mass of 0.580 kg. Calculatgaf 6m fn9:poe0.s8e se (a) its moment of inertia about its center, $\approx$ $kg \cdot m^2$ (b) the applied torque needed to accelerate it from rest to 1500 rpm in 5.00 s if it is known to slow down from 1500 rpm to rest in 55.0 s。 $m \cdot N$