Consider the arm of a person, carrying a weight W in the hand as shown above....

  

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Consider the arm of a person, carrying a weight W in the hand as shown above. Consider that the only muscle that fires during this activity is the biceps muscle of the upper arm. This muscle inserts into the scapula (which we can assume to be grounded) and into the radius bone of the forearm. The elbow joint may be idealized as a pin joint. Draw a free-body diagram of the forearm, including all external and reaction forces. Assume that the weight of the forearm is negligible compared to the weight W. Solve for: A. The biceps force required to hold the weight in the shown position B. The elbow joint reaction force C. Assuming that W = 20 lbf, how much muscle force is required to hold that weight? What is the compressive force acting on the elbow joint articulation? Comment on the implication of these values to human physiology. 15 in biceps -weight shoulder joint scapula humerus elbow joint 1.5 in radius Consider the arm of a person, carrying a weight W in the hand as shown above. Consider that the only muscle that fires during this activity is the biceps muscle of the upper arm. This muscle inserts into the scapula (which we can assume to be grounded) and into the radius bone of the forearm. The elbow joint may be idealized as a pin joint. Draw a free-body diagram of the forearm, including all external and reaction forces. Assume that the weight of the forearm is negligible compared to the weight W. Solve for: A. The biceps force required to hold the weight in the shown position B. The elbow joint reaction force C. Assuming that W = 20 lbf, how much muscle force is required to hold that weight? What is the compressive force acting on the elbow joint articulation? Comment on the implication of these values to human physiology. 15 in biceps -weight shoulder joint scapula humerus elbow joint 1.5 in radius