1st Edition

ISBN: 9781938168048

Author: Paul Peter Urone, OpenStax, Roger Hinrichs

Publisher: OpenStax

Concept explainers

The centre of gravity is a property that is based on the geometry of a rigid body or any particle. It is described as an equilibrium point or a hypothetical location where the total weight of the body is concentrated.

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Chapter 9, Problem 32PE

Even when the head is held erect, as in Figure 9.41, its center of mass is not directly over the principal point of support (the atlanto-occipital joint). The muscles at the back of the neck should therefore exert a force to keep the head erect. That is why your head falls forward when you fall asleep in the class. (a) Calculate the force exerted by these muscles using the information in the figure. (b) What is the force exerted by the pivot on the head?

Chapter 9, Problem 32PE, Even when the head is held erect, as in Figure 9.41, its center of mass is not directly over the

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Chapter 9, Problem 31PE

Chapter 9, Problem 33PE

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Chapter 9 Solutions

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