[填空题]
A cooling fan is turned (lm648 72te d)ufdfrb nsb-fco f ie:nm/v2pylkd/ q2,ff when it is running at 850rev/min It turns 1500 revolutions before it nik 2 fm/: dy,/2eqvlpcomes 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