[填空题]
A 70-cm-diameter whee/ 4v( qoymcjp9) +qocdv( z7wbl accelerates uniformly about its ceh7 +31 elwyn avy1dk)f lxzm.4nter from 130 rpm to 280 rpm+k 1vxh1yzln7.3am)wdy fl4e in 4.0 s. Determine (a) its angular acceleration,$\approx$ $rad/s^2$(Round to one decimal places) (b) the radial and tangential components of the linear acceleration of a point on the edge of the wheel 2.0 s after it has started accelerating. $a_R$ $m/s^2$ $a_{tan}$ $m/s^2$