[填空题]
A cooling fan is turned off when it is running - +lz3ti-t q,tb(k6cqo pc 2cyk- ;ummjy; e9sdizs*0u k )cb-at 850rev/min It turns 1500 revolutions before it comes tosdb9)ju *zeics - yk0; 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