[填空题]
A cooling fan is turned off w v , ydu:45yo .x,mlk+fbxkdqhr;3f5ehen it is runnink)7lg-eei *alg at 850rev/min It turns 1500 revolutions before it comes to * -lleae7g)k ia 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