Consider the position of the human head and neck shown below, in static equilibrium: FM FJ FM: The force exerted by the neck extensor muscles, which makes angle 0 with the horizontal FJ: The force at the atlanto-occipital joint (the joint between the head and neck), which makes angle ß with the horizontal W: The weight of the head A: The point where neck extensor muscles act on the skull B: The point where the first cervical vertebra contacts the atlanto-occipital joint (the point of the head- neck joint) C: The center of gravity of the head 0: The intersection of forces W, FMm, and Fj a) Set up the appropriate statics equations to solve for forces FM and FJ. b) Determine equations for FM and FJ as functions of W, ß, and 0. c) Determine FM and Fj assuming the head has a mass of 5 kg, 0 = 30°, and ß = 60°.

Consider the position of the human head and neck shown below, in static equilibrium: FM FJ FM: The force exerted by the neck extensor muscles, which makes angle 0 with the horizontal FJ: The force at the atlanto-occipital joint (the joint between the head and neck), which makes angle ß with the horizontal W: The weight of the head A: The point where neck extensor muscles act on the skull B: The point where the first cervical vertebra contacts the atlanto-occipital joint (the point of the head- neck joint) C: The center of gravity of the head 0: The intersection of forces W, FMm, and Fj a) Set up the appropriate statics equations to solve for forces FM and FJ. b) Determine equations for FM and FJ as functions of W, ß, and 0. c) Determine FM and Fj assuming the head has a mass of 5 kg, 0 = 30°, and ß = 60°.

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter5: Displacement And Force In Two Dimensions

Section: Chapter Questions

Problem 82A

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