[填空题]
A 70-cm-diameter wheel accelerates uniformly about its cen+yp :rh12))jps7r,jwt.dos sna 0grtter fho7keh01 n*5 .gpxd lerom 130 rpm to 280 rpm in 4.0 s. Determ * 7.5hepoxndlke1h0 gine (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. $a_R$ $m/s^2$ $a_{tan}$ $m/s^2$