The leg and cast in Figure P4.18 weigh 260 N, with the center of mass as indicated by the blue arrow in the diagram. The counterbalance w2 weighs 115...

The leg and cast in Figure P4.18 weigh 260 N, with the center of mass as indicated by the blue arrow in the diagram. The counterbalance w2 weighs 115 N. Determine the weight w1 and the angle α needed in order that there be no force exerted on the hip joint by the leg plus cast.