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Angular motions in revolutions, degrees, and radians
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· One complete cycle of 360”ć is one revolution.
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· One complete revolution is 2 radians.
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· Relating the two, 360”ć = 2 radians or 1 radian = 57.3”ć. |
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A speedometer as our starting model |
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We use angular position to describe the position of a particle during circular motion. |
Angular displacement: |
Average angular velocity:
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Instantaneous angular velocity:
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Angular velocity is a vector |
You can visualize the position of the vector by sweeping out the angle with the fingers of your right hand. The position of your thumb will be the position of the angular velocity vector. This is called the ”°right-hand rule.”±
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Angular acceleration |
Average angular acceleration: |
(Instantaneous) angular acceleration: |
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Comparison of linear and angular kinematics |
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Linear and angular quantities related |
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