[填空题]
A cooling fan is turned off when it is run seawo/5*lxqoo ,p0 u:ning at 850reqy(-yg:wchxx 8+ u rw: 9q*lwcv/min It turns 1500 revolutions before it comq*:l9wc+y: hr8 (- w uyqcwxxges 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