Spinning Spool Physics Q: Is Circumference Dist. = Center Dist.?

AI Thread Summary
The discussion revolves around the physics of a spinning spool, specifically whether the distance traveled by the circumference equals the distance from the center of the circle during one complete turn. It is clarified that when the spool rolls, the top moves faster than the center, leading to different distances traveled. A suggestion is made to experiment with a cut-out circle to visualize the concept. The key takeaway is that the spool rotates around its point of contact with the ground, influencing its motion. Understanding these dynamics is crucial for solving related physics problems.
zabachi
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I have a question about a spinning spool, there is a spool spinning and is the sistance traveled by the circumference the same as the center of the circle? You can refer to the diagram attached for a question I had trouble with from a physics olympiad. The answer
was (B).
Thanks in advance!
 

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zabachi said:
I have a question about a spinning spool, there is a spool spinning and is the sistance traveled by the circumference the same as the center of the circle?
I assume you are asking: When the rolling spool makes one complete turn, has it traveled a distance equal to the circumference?

What do you think? (Cut out a circle and try it!)
 
zabachi said:
You can refer to the diagram attached for a question I had trouble with from a physics olympiad. The answer was (B).
The top of the spool moves twice as fast as the center. But what happens when you pull it under the center?

https://www.youtube.com/watch?v=dvyii6QBLtw
 
I think the easiest way to figure it out is to consider a very small movement. The spool as a whole rotates about its point of contact with the ground.
 
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