a person with a femoral fracture lies in traction in order to to reset the healing bone. (a) based on the schematic, discuss qualitatively all of the places where friction acts in this system. (b) for the sake of this problem, pretend that the pulleys are replaced with fixed, smooth metal bars, and that the rope can slide around them with coefficient of static friction μ = 0.02. assuming a reasonable value for w and using other visual clues from the diagram, estimate the total vector force transmitted to the knee assuming (i) impending motion of the weight upward and (ii) impending motion of the weight downward?