A700-gram grinding wheel 28.5 cm in diameter is in the shape of a uniform solid disk. (we can ignore the small hole at the center.) when it is in use, it turns at a constant 210 rpm about an axle perpendicular to its face through its center. when the power switch is turned off, you observe that the wheel stops in 41.0 s with constant angular acceleration due to friction at the axle. part a what torque does friction exert while this wheel is slowing down?