Hey all, I am just doing Kirchoffs rules right now. So we have a couple sign conventions we were taught. I just need to make sure my reasoning makes sense for the 3 and 4 rule.(adsbygoogle = window.adsbygoogle || []).push({});

1. When we travel through a source of emf from + --> - we get a - voltage.

2. When we travel through a source of emf from - ---> + we get a + voltage

3 When we travel through a resistor in the same direction as the assumed current we get a -RI because current goes in the same direction as decreasing potential.

4. When we travel through a resistor in the opposite direction as the assumed current, we get a +RI.

So for 3, because we are going in the direction of the assumed current, current always flows from the high potential to the low potential, just as when we consider a positive point charge the potential gradient weakens as we move further away. So the RI term is - which indicates the potential difference at that location is decreasing.

for 4, because we are going opposite the direction of current, we are moving further away from a lower potential difference and closer to a higher potential difference. Like transversing a Potential gradient from infinity to the source, it gets stronger and stronger and the potential is higher.

I really need to make sure my use of potential difference and potential is not convoluted because I tend to misuse the terms.

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# Kirchoff Rule Sign Conventions, Need Clarity.

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