Average Velocities: Constant Speed on Circular Path

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Average velocity is defined as net displacement divided by time, which results in zero for an object moving at constant speed on a circular path when it returns to the starting point, as the net displacement is zero. In contrast, average speed, which measures the total distance traveled over time, is not zero. This distinction often leads to confusion, especially in educational settings. A common mistake is to conflate average velocity with average speed, as seen in a professor's example. Understanding this difference is crucial for accurately interpreting motion in circular paths.
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I have a question about average velocity. It's defined as the net displacement divided by the time. So if I have an object moving at a constant speed on a circular path, is the average velocity zero every time the object returns to the starting point? My reasoning is that the net displacement is zero.
 
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Your reasoning is correct!
 
Yes that's right. The average velocity is zero. But the average speed is not.
 
Thaakisfox said:
Yes that's right. The average velocity is zero. But the average speed is not.

Ok, that's what I thought. My professor worked out a problem where the object returned to the starting point, and claimed a value for the average velocity. I think she meant average speed and left me confused. :confused:
 
Well yes, that is a common mistake ;)
 

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