10.53. Set Up: Take the pivot at the shoulder joint and let counterclockwise torques be positive. Let be upward and let be to the right. and are the weights of his upper arm and forearm, respectively. is the weight held in his hand. Solve: (a) The free-body diagram is given in Figure 10.53. Figure 10.53 (b) gives Reflect: The force T from the muscle has a small perpendicular component and a small level arm, so its magnitude is much larger than the total weight being supported. 10.54. Set Up: The only difference from Problem 10.53 is that now the weight of the 2.50 kg object and of the forearm act at the elbow, a distance of 26.0 cm from the shoulder. Solve: gives 10.55. Set Up: The precession angular velocity is 10.56. Set Up: The precession angular velocity is The total mass of the gyroscope is Solve: (a) (b) (c) If the figure in the problem is viewed from above, is in the direction of the precession and is along the axis of the rotor, away from the pivot. 10.57. Set Up:
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