[填空题]
A 70-cm-diameter wheel accelerates uniformly about its c+(/blbuosdnx;r d 8p6 ente/-bdd/i,bmq i x0 p17 -2te7pvuzxrjb r from 130 rpm to 280 rpm i7ub-dp xvbbj pi-dz/7t/i,2r xme0q 1n 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. $a_R$ $m/s^2$ $a_{tan}$ $m/s^2$