Rotational dynamics: Putting it all together Leg lift You are doing...

Rotational dynamics: Putting it all together

Leg lift You are doing one-leg leg lifts (Figure P8.67) and decide to estimate the force that your iliopsoas muscle exerts on your upper leg bone (the femur) when being lifted (the lifting involves a variety of muscles). The mass of your entire leg is 15 kg, its center of mass is 0.45 m from the hip joint, and its rotational inertia is 4.0 kg . m², and you estimate that the rotational acceleration of the leg being lifted is 35 rad/s². For calculation purposes assume that the iliopsoas attaches to the femur 0.10 m from the hip joint. Also assume that the femur is oriented 15° above the horizontal and that the muscle is horizontal. Estimate the force that the muscle exerts on the femur.