[填空题]
(a) A grinding wheel 0.3.*nj.d bvn1vj5 m in d u f+p6x0,tb2hup lp8u5mso (miameter rotates at 2500 rpm. Calculate its angular veloci6 tf o, pum 2hmbl+up(85sxu0pty 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$