How Do Voltage Arrows Indicate Polarity?

AI Thread Summary
Voltage arrows indicate the direction of potential difference, typically pointing from the positive to the negative terminal. In the example of a 20V voltage drop from point A to point B, point A is at a higher potential (+20V) and point B is at a lower potential (0V). Therefore, point A is positive, and point B is negative. Understanding this convention is crucial for analyzing circuits and voltage relationships. The discussion emphasizes the importance of recognizing the direction of voltage arrows to determine polarity accurately.
cytochrome
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I see a lot of voltage drops being represented as an arrow. Say a voltage of 20V is represented as an arrow from point a to point b.

What is the polarity of and b then? Do the arrows to represent voltage usually go from + to - or from - to +?

Thanks for your time.
 
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By convention the arrows represent a positive change in potential so they point to the higher voltage.
 
I'm still trying to make sure I really understand this. Can someone answer my example question?

Say a voltage of 20V is represented as an arrow from point a to point b. What is the polarity of a and b then?
 
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