D. leftright updown The biceps brachii is the typical muscle we associate with forearm curls. The forearm pivots aboutthe elbow joint and the biceps muscle inserts along the radius (one of two major forearm bones),d₁ = = 5 cm from the pivot. In our case, consider a forearm of length of d3 = 34 cm and weight ofW = 3lbs, with a center of mass shifted toward the pivot, at d₂ = 15 cm from the elbow. There is areaction force R at the elbow joint not shown in the figure. As a first approximation, assume thebiceps muscle inserts at a 90 degree angle while the forearm is held parallel to the ground.Assume all quantities are correct to 2 significant figures.b)CaMElWa) If the person described above is holding a 22 lb object exerting a force F in static equilibrium, whatis known about the tension force M applied by the biceps brachii?FThe force is less than 22 lbs.The force is equal to 22 lbs.The force is greater than 22 lbs but less than 25 lbs. chii.The force is equal to 25 lbs.The force is greater than 25 lbs.conditions of static equilibrium, a) If the person described above is holding a 22 lb object exerting a force F in static equilibrium, whatis known about the tension force M applied by the biceps brachii?Fb) Using the numerical values stated in the problem and the conditions of static equilibrium,calculate the tension force M in lbs, applied by the biceps brachii.Enter to 2 significant figuresM =lbsc) Using the numerical values stated in the problem, your answer for (b), and the conditions of staticequilibrium, calculate the magnitude of the reaction force R in lbs, produced at the elbow joint.Enter to 2 significant figuresR =lbsd) In what direction is the reaction force that you calculated in part c?e) The forearm is lowered from horizontal. The biceps brachii now meets the radial arm at an angleof 60 degrees rather than 90 degrees. How does this effect the magnitude of the tension force Mcompared to the horizontal arm orientation?Hint: It might be helpful to refer to torque equilibrium for this case. What happens to the momentarm of all forces?M must increase to maintain equilibrium.M does not need to change to maintain equilibrium.M must decrease to maintain equilibrium.

Answered: Image /qna-images/answer/b6c5f135-da77-4a0b-a03f-8c55b1f834f0.jpg

The biceps brachii is the typical muscle we associate with forearm curls. The forearm pivots about the elbow joint and the biceps muscle inserts along the radius (one of two major forearm bones), d₁= = 5 cm from the pivot. In our case, consider a forearm of length of d3 = 34 cm and weight of W = 3lbs, with a center of mass shifted toward the pivot, at d₂ = 15 cm from the elbow. There is a reaction force R at the elbow joint not shown in the figure. As a first approximation, assume the biceps muscle inserts at a 90 degree angle while the forearm is held parallel to the ground. Assume all quantities are correct to 2 significant figures.

The biceps brachii is the typical muscle we associate with forearm curls. The forearm pivots about the elbow joint and the biceps muscle inserts along the radius (one of two major forearm bones), d₁= = 5 cm from the pivot. In our case, consider a forearm of length of d3 = 34 cm and weight of W = 3lbs, with a center of mass shifted toward the pivot, at d₂ = 15 cm from the elbow. There is a reaction force R at the elbow joint not shown in the figure. As a first approximation, assume the biceps muscle inserts at a 90 degree angle while the forearm is held parallel to the ground. Assume all quantities are correct to 2 significant figures.

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter10: Rotational Motion

Section: Chapter Questions

Problem 23P: Find the net torque on the wheel in Figure P10.23 about the axle through O, taking a = 10.0 cm and b...

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