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Rolling as pure rotation:
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Kinetic Energy: |
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A rigid body in motion about a moving axis |
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A primitive yo-yo |
Example: The string unwinds without slipping or stretching. Find the speed and the acceleration of the center of mass.
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The race of objects with different moments |
Example: Assuming h is much larger than the radii of the rolling bodies and pure rotation. Due to the conservation of mechanical energy,
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Rolling friction |
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Consider the acceleration of a rolling sphere |
Example: A solid bowling ball rolls without slipping. Assuming the ramp is solid. Find out the ball’s acceleration.
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The above friction force is static and is the minimum friction force required to prevent the ball from slipping.
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Work and power in rotational motion |
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