[填空题]
A grinding wheel is abtaib z9,u+rgw-,b g * uniform cylinder w lxu1w789 at 2mf8u2rusn gosrqb +fq)36q8kwith a radius of 8.50 cm and a mass of 0.580 k78k2m3 +a268lnswuruxgfq b)1ruq 9sq8 tf wog. Calculate (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。 $m \cdot N$