Basic Biomechanics
7th Edition
ISBN: 9780073522760
Author: Susan J Hall
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 13, Problem 7AP
A worker leans over and picks up a 90-N box at a distance of 0.7 m from the axis of rotation in her spine. Neglecting the effect of body weight, how much added force is required of the low back muscles with an average moment arm of 6 cm to stabilize the box in the position shown? (Answer: 1050 N)
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With the shoulder flexed at 30°, the moment arm of the deltoid muscle is 2.0 cm. Solve
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STATIC EQUILIBRIUM EQUATIONS
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Chapter 13 Solutions
Basic Biomechanics
Ch. 13 - Why does a force directed through an axis of...Ch. 13 - Why does the orientation of a force acting on a...Ch. 13 - A 23-kg boy sits 1.5 m from the axis of rotation...Ch. 13 - Prob. 4IPCh. 13 - Two people push on opposite sides of a swinging...Ch. 13 - Prob. 6IPCh. 13 - Prob. 7IPCh. 13 - Prob. 8IPCh. 13 - A 10-kg block sits motionless on a table in spite...Ch. 13 - Prob. 10IP
Ch. 13 - A 35-N hand and forearm are held at a 45 angle to...Ch. 13 - A hand exerts a force of 90 N on a scale at 32 cm...Ch. 13 - A patient rehabilitating a knee injury performs...Ch. 13 - A worker leans over and picks up a 90-N box at a...Ch. 13 - A man carries a 3 m, 32-N board over his shoulder....Ch. 13 - A therapist applies a lateral force of 80 N to the...Ch. 13 - Tendon forces Ta and Tb are exerted on the...
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