[填空题]
A cooling fan is turned off when it isds:kc ve:ys+ x6)fq+a running at 850rev/ lhs3xk 6,.alwmin It turns 1500 revolwahlsk,xl.3 6 utions before it comes 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