[填空题]
A cooling fan is turne3oyob(s5 *jf w2t k0jnd br24jl2qvg (e3 mf *uroff when it is running at 850rev/min It turns 1500 revolutions beforvl*3f2jmegu4 b2 (r qre 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