[填空题]
A cooling fan is turned off when it is running at 850rev/ a4oak3s,0k*u .ibu7f at7u avmit:f0 spyjj1 lcw51.xoqh39c dn It turns 1500 revolutions before it cojhj t:51lf1qp 9 d30. wcsxycomes 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