An architecture student working at a drafting table requires some muscle action in order to support her head. As shown in the figure, three forces act on her head. If the force provided by muscles is FM = 75 N and the weight of her head is W = 38 N, determine the magnitude and direction of the force provided by the upper vertebrae F, to hold her head stationary. Assume that this force acts along a line through the center of mass of her head as do the weight and muscle force. (Assume the +x-axis to be to the right.) magnitude direction ° measured clockwise from the -x-axis CG F.

An architecture student working at a drafting table requires some muscle action in order to support her head. As shown in the figure, three forces act on her head. If the force provided by muscles is FM = 75 N and the weight of her head is W = 38 N, determine the magnitude and direction of the force provided by the upper vertebrae F, to hold her head stationary. Assume that this force acts along a line through the center of mass of her head as do the weight and muscle force. (Assume the +x-axis to be to the right.) magnitude direction ° measured clockwise from the -x-axis CG F.

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter8: Rotational Motion

Section: Chapter Questions

Problem 69A

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An architecture student working at a drafting table requires some muscle action in order to support her head. As shown in the figure, three forces act on her head. If the force provided by muscles is FM = 60 Nand the weight of her head is W = 36 N,determine the magnitude and direction of the force provided by the upper vertebrae FV to hold her head stationary. Assume that this force acts along a line through the center of mass of her head as do the weight and muscle force. (Assume the +x-axis to be to the right.) Magnitude = ? Direction (measured clockwise from the −x axis) = ?
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