2. (25 points) A 200 lb man stands on his right foot while carrying a 100 lb in his left hand. The center of mass of the bag is 12 in from his center of mass as shown in the figure below. (a) Show that the placement of the foot (as shown) leads to no net torque in the body. (b) Find the force (its magnitude and direction) on the head of the support femur and the force in the hip abductor muscle by examining the right leg. (c) Compare your answers in parts (a) and (b) with what was found for the man holding no mass - without and with a cane (for W₁ = 880 N = 200 lb). Are the forces here greater than for a (200 lb +100 lb) 300 lb man (with no cane). Why? (The muscle angle and leg mass are only trivially different for the problem given here and those analyzed above.) 36" 71% 200 lb. c.g 31lb. 20" 100 lb. 300 lb. 300 lb. Figure 1: Forces on hip and femoral head while standing on one leg and lifting a weight with the opposite hand.

Fig: 1