[填空题]
A 70-cm-diameter wheel accelerates uniformly about it81exc 9(n5(y wq zxjhns cente*r p:3pxz-jh jw,nbo9at 8,qpr from 130 rpm to 280 rpm in 4.0 s. Determine- pozjt,p*x9 qjnb p:3a,w8 hr (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. $a_R$ $m/s^2$ $a_{tan}$ $m/s^2$