[填空题]
The blades in a blender rotate at a rate of 6500 rpm. When thd1 7hbeq-9g ,kqoy u8hprd.uar ic)mr3ki1 *0e motor is turned off during operation, the blades slow to rest in 3.0 s. What )0piac3.rr r1* mukdiis the angular acceleration as the blades slow down? $rad/s^2$