[填空题]
(a) What is the angul- j* me.lu8rsrar momentumwbcewud o -j k1x6,okj) 11+os of a 2.8-kg uniform cylindrical grinding wheel of radius 18 cm when rotating at 1500 rp1obj-u ,dceo1+okxs 1w 6j wk)m? $kg \cdot m^2$ (b) How much torque is required to stop it in 6.0 s? $m \cdot N$