Question

The femur of a human leg (mass 10 kg, length 0.9 m) is in traction, as shown in the figure below. The center of gravity of the leg is one-third of the distance from the pelvis to the bottom of the foot. Two objects, with masses m1 and m2, are hung using pulleys to provide upward support. A third object of 8 kg is hung to provide tension along the leg. The body provides tension as well. What is the mathematical relationship between m1 and m2? Is this relationship unique in the sense that there is only one combination of m1 and m2 that maintains the leg in static equilibrium?

Answer 1

The mathematical relationship between m1 and m2 is m1 + m2 = 8 kg. This relationship is not unique, as there are multiple combinations of m1 and m2 that can be used to maintain the leg in static equilibrium. For example, m1 could be 4 kg and m2 could be 4 kg, or m1 could be 6 kg and m2 could be 2 kg.