[填空题]
A cooling fan is turnr kmqsuazwy78,+ jnrve 2*s.y 7g. )wbed o5j9(maa x9 /+arl wlgpff when it is running at 850rev/min It turns 1500 revolutions before it comes aga5 a 9/jml9w+pxr(lto 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