[填空题]
A cooling fan is turned off when it is runningqhwq50v-27qk t pwro; at 8plm*hc8 0f7r addoyf..(ch+tzk uv3 850rev/min It turns 1500 revolutions before it co +8z 7 f 3cmhfcdh.(yvu*rkta8old.0pmes 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