1. The PASCO human arm model is configured such thatthe cord representing the bicep is perfectly vertical andthe forearm is at 90° (in the figure to the right, the cordis not quite vertical). A mass of 100 g is attached to thehand. Draw a free-body diagram on the figure to theright showing all forces which act on the forearm.The force of the bicep F on the armThe force of the humerus FH on the armThe weight of the forearm WThe mass in the hand Wm100 gBe careful to draw the force vectors with tails beginning at the point where the force is actuallyapplied to the forearm.2. Consider the free body diagram below. Determine the perpendicular component F̟ of theforce F exerted by the biceps brachii on the forearm. Use the fact that cos 0 = H/B to writethis component directly in terms of the humerus length H and the biceps length B.H3. If the forearm is in equilibrium, then there is no angular acceleration and therefore the sum ofthe torques applied to the forearm must be zero. Using your answer above, write an equationshowing the relationship between the magnitudes of the applied forces F, WA, and Wm.Assume that the center of mass of the arm is half of the arm length l. Choose your origin to bewhere the force of the humerus is applied, so that we don't need to know that force.4. What dothink are some disadvantages of your muscle having such a short lever arm?5. What are some advantages of your muscle having such a short lever arm?

Given information: The Force of the Bicep on the arm = F The Force due to Humerus on the arm = FH…

The PASCO human arm model is configured such that the cord representing the bicep is perfectly vertical and the forearm is at 90° (in the figure to the right, the cord is not quite vertical). A mass of 100 g is attached to the hand. Draw a free-body diagram on the figure to the right showing all forces which act on the forearm. • The force of the bicep F on the arm • The force of the humerus Fy on the arm • The weight of the forearm WA • The mass in the hand Wm Be careful to draw the force vectors with tails beginning at the point where the force is actually applied to the forearm. 100

The PASCO human arm model is configured such that the cord representing the bicep is perfectly vertical and the forearm is at 90° (in the figure to the right, the cord is not quite vertical). A mass of 100 g is attached to the hand. Draw a free-body diagram on the figure to the right showing all forces which act on the forearm. • The force of the bicep F on the arm • The force of the humerus Fy on the arm • The weight of the forearm WA • The mass in the hand Wm Be careful to draw the force vectors with tails beginning at the point where the force is actually applied to the forearm. 100

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter4: Coplanar Equilibrium Analysis

Section: Chapter Questions

Problem 4.41P: The center of gravity of the 3000-lb car is at G. The car is parked on an incline with the parking...

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