[填空题]
The blades in a blendeh2bwbiy-u*;no9d -)wa v8ctrr e/dwf(vj pd2:rotate at a rate of 6500 rpm. When the motor is turned off during operation, the blades slow to rest in 3.0 s. What is the angular ac 2ewd/jpf(d v:celeration as the blades slow down? $rad/s^2$