[填空题]
Starting from rest in the pit arl-ozea 00xtq8 ea, a race car accelerates at a jbrmy: b2(gkf o)c2o7uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical value7)gor 2j(bmoyb2:c k f in the blanks)
(a) Calculate the tangential acceleration. $m/s^2$
(b) Calculate the radial acceleration when the instantaneous speed is equal to 30 m/s. $m/s^2$
