During most of the stance phase of the gait, the knee flexion is less than 20º. What force must the quadriceps muscle apply to maintain this flexion while standing on one leg? The patient's weight is 836N, assuming that the distance from the center of the joint to the line of gravity is 5 cm and the distance perpendicular to the center of the joint towards which the muscle acts is 5 cm, and the muscle acts ( pull) at 60º to the horizontal.

During most of the stance phase of the gait, the knee flexion is less than 20º. What force must the quadriceps muscle apply to maintain this flexion while standing on one leg? The patient's weight is 836N, assuming that the distance from the center of the joint to the line of gravity is 5 cm and the distance perpendicular to the center of the joint towards which the muscle acts is 5 cm, and the muscle acts ( pull) at 60º to the horizontal.

University Physics Volume 1

18th Edition

ISBN:9781938168277

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

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

Chapter5: Newton's Law Of Motion

Section: Chapter Questions

Problem 61P: Show that, as explained in the text, a force F exerted on a flexible medium at its center and...

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