Question

The dynamic duo of Je’Kai and Oluwalani have an acrobatic routine where Je’Kai applies a 112 N external force to Oluwalani’s horizontally outstretched right leg at a point x = 0.35 m and y = 0.03 m with his hip socket as the origin. Find the torque vector about the hip socket (origin) if the applied force during the routine points in (a) the x-direction only and (b) if it points in the z-direction only. Suppose that the 112 N external force is directed vertically down through his leg’s center of mass, in the y-direction, but does not include the 155 N weight of his own leg. If his rectus femoris in his quadricep is capable of applying a force of 925 N along the muscle at an angle of 21˚ above the horizontal at an attachment point of x = 0.45 m from the hip socket, then (c) is the rectus femoris alone capable of sustaining his leg in this position?

Answer 1