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Kinesiology 2241A/B Lecture Notes - Lecture 30: Angular Velocity, Gyration

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uwostudent70
4 Jan 2021
School
Western University
Department
Kinesiology
Course
Kinesiology 2241A/B
Professor
Thomas Richard Jenkyn

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Document Summary

Kinesiology 2241b lecture 30: freely rotating bodies i. When the body is airborne it is not possible to apply reaction forces to it. Therefore, the center of mass follows a parabolic pathway, and the angular momentum is constant. However, this doesn"t mean we can"t use the angular momentum that is available to rotate in numerous ways while in the air. When in the air, rotation can occur about one, two, or three of the principle axes simultaneously. The axis of rotation for each component of the rotation must pass through the center of mass. No matter what motions the segments do relative to the center of mass, they cannot change its pathway from parabolic. But it is in the athlete"s control how they move while airborne and in what orientation they land. As long as segment motions are symmetrical, angular momentum in each anatomical plane will be constant. Otherwise angular momentum can be transferred from one plane to another.

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