[填空题]
A cooling fan is tur09mgayjb qg 7j+tde6u.ks)d 0fat 97 1fkr/ubned off when it is running at 850rev/min It turns 1500 revolutions before it comes to a st 17akt/f rfu9bop. (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