[填空题]
A cooling fan is turned off when it is running at 850rev/j5dcn5qd d :-xmin It j3hr.fivre (dn/8qga n;lr4 ( turns 1500 revolutions before it comes (eia l/ndf ngh(.jqrrv3;4 r8to 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