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mwoods18
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Homework Statement
During an isometric exercise for strengthening the biceps, an external force of 200 N is applied perpendicular to the forearm 0.3 meters from the center of rotation of the elbow joint. The elbow is flexed to 90 degrees and the forearm is supinated. The force produced by the biceps muscle, which for our purposes is the only active muscle, has a moment arm of 0.04 meters and a line of application parallel to the long axis of the humerus. How large is the force (B) must the biceps muscle generate to counteract this torque? The weight of the forearm and hand is 13.7 Newtons and the length of the forearm and hand is 0.4 cm. The center of mass is 68% of the length of the forearm and hand from the elbow to the wrist.
Homework Equations
Sum of Torque= 0
F*FA=R*RA
The Attempt at a Solution
(0.028m)(200N)=(0.272m)(Fmuscle)
Fmuscle=20.6N