n the head is held erect, as shown in the figure, its center of mass is not directly over the principal point of support (the atlanto-occipital joint, Point A). 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. F If the head weighs 51 N, calculate the force exerted by the muscles FM using the information in the figure. Assume that X1 = 5.3 cm, X2 = 2.5 cm, and JFw|=SIN.

n the head is held erect, as shown in the figure, its center of mass is not directly over the principal point of support (the atlanto-occipital joint, Point A). 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. F If the head weighs 51 N, calculate the force exerted by the muscles FM using the information in the figure. Assume that X1 = 5.3 cm, X2 = 2.5 cm, and JFw|=SIN.

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter10: Fixed-axis Rotation

Section: Chapter Questions

Problem 117AP: Two children push on opposite sides of a door during play. Both push horizontally and perpendicular...

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