College Physics
1st Edition
ISBN: 9781938168000
Author: Paul Peter Urone, Roger Hinrichs
Publisher: OpenStax College
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Chapter 9, Problem 29PE
A device for exercising the upper leg muscle is shown in Figure 9.39, together with a schematic representation of an equivalent lever system. Calculate the force exerted by the upper leg muscle to lift the mass at a constant speed. Explicitly show how you follow the steps in the Problem-Solving Strategy for static equilibrium in Applications of Statistics, Including Problem-Solving Strategies
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A device for exercising the upper leg muscle is shown in Figure shown, together with a schematic representation of an equivalent lever system. Calculate the force exerted by the upper leg muscle to lift the mass at a constant speed. Explicitly show how you follow the steps in the Problem- Solving Strategy for static equilibrium in(Hint): Applications of Statistics, Including Problem-Solving Strategies.
One person was doing a knee extensor muscle training, he used a dumbbell (mass = 10.2 kg) strapped to the ankle joint and was 0.4 m from the knee joint (see attached figure). The dumbbell was 0.3 m away from the knee joint in the horizontal direction.
If the lever arm for the knee extensor muscle force was 0.04 m about the knee joint center, what amount of force must the knee extensor muscle produce to hold the leg in the above position? (Ignore the weight of the leg)
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Modelled after problem 5 in the Problems_Torque_Statics: A 16.19-m-high and 11.44-m-long wall under construction and its bracing are shown in the figure. The wall is in stable equilibrium without the bracing but can pivot at its base. Calculate the force exerted by each of the 10 braces if a strong wind exerts a horizontal force of 673.77 N on each square meter of the wall. Assume that the net force from the wind acts at a height halfway up the wall and that all braces exert equal forces parallel to their lengths. Neglect the thickness of the wall. The angle between the braces and the wall is as shown in the figure as 35 degrees.
answer is 21,756.7113 but how?
Chapter 9 Solutions
College Physics
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- One person was doing a knee extensor muscle training, he used a dumbbell (mass = 10.2 kg) strapped to the ankle joint and was 0.4 m from the knee joint (see attached figure). The dumbbell was 0.3 m away from the knee joint in the horizontal direction. if the lever arm for the knee extensor muscle force was 0.04 m about the knee joint center, what amount of force must the knee extensor muscle produce to hold the leg in the above position? (Ignore the weight of the leg)arrow_forwardModeled after problem 5 in the Problems_Torque_Statics: A 13.98-m-high and 12.18-m-long wall under construction and its bracing are shown in the figure. The wall is in stable equilibrium without the bracing but can pivot at its base. Calculate the force exerted by each of the 10 braces if a strong wind exerts a horizontal force of 586.31 N on each square meter of the wall. Assume that the net force from the wind acts at a height halfway up the wall and that all braces exert equal forces parallel to their lengths. Neglect the thickness of the wall. The angle between the braces and the wall is as shown in the figure as 35 degrees.arrow_forwardAn athlete strengthens her leg and knee by doing "leg curls." While sitting on a bench with the leg initially bent at the knee, she supports a weight with the foot. She then slowly raises the foot and lower leg, with the upper leg held stationary. Find the tension in the quadriceps tendon for the position shown in the figure below. (Let w = 225 N, D = 44 cm and d = 5.5 cm.) please solve thank youarrow_forward
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