[填空题]
A cooling fan is turned oza;n5lh yr+ 2byjg( j-ff whenm.qn xk) lwoujua,b/yl6j2lf**t86 h it is running at 850rev/min It turns 1500 revolutions before it comes mkjtl2*bah.6,q lwfj 86n)oxly *u u/ to a stop. (a) What was the fan’s angular acceleration, assumed constant? $\frac{rad}{s^2}$ (b) How long did it take the fan to come to a complete stop? s