[填空题]
(a) A grinding wheel 0.35 m in diametepqa-ud3m70t r r rotates at 250 mzxtun*onzw+3n/ 7: i0 rpm. Calculate its angular velociti xuzo*7w/n3mn :z+ nty in $rad/s$ $\omega$ = $rad/sec$ (b) What are the linear speed and acceleration of a point on the edge of the grinding wheel? v = $m/s$ $a_R$ = $ m/s^2$