[填空题]
A cooling fan is tur(jul6ut3zhx 5ned off when it is runnh*k)z+mnc0ep0xg c f1as7 s ,sing at 850rev/min It turns 1500 revolutice7kf ,1nsgash +*szx0) mc0 pons 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