8–7. The block brake conit of a pin-connected lever and
friction block at B. The coefficient of tatic friction between
the wheel and the lever i m = 0. 3, and a torque of 5 N # m
i applied to the wheel. Determine if the brake can hold the
wheel tationary when the force applied to the lever i
(a) P = 30 N, (b) P = 70 N