[填空题]
A cooling fan is turh* c8 --9mar 6k6b wegrkig-jmnojudnqr0/6a . ed off when it is running at 850rev/min It turns 1500 revolutionr.oq 6duj 0/ans 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