[填空题]
A 70-cm-diameter wheel accelerates uniformly amhnxg +g-y1*5b( zcncbout i/wv- obf wq ysu2f)s/)bka6x5ts center from 130 rpm to 280 rpm in 4.0 s. D/abvsf k6q)w2)fw5ub - xs/yo etermine (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. $a_R$ $m/s^2$ $a_{tan}$ $m/s^2$