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sokrates said:Thanks, I think the reason I assumed that potential was some intrinsic property was because I was confusing it with the electric field. I did some reading and realized that they're different things. I guess potential is meaningless unless there is some avenue for it to do work through (i.e. an impedance).
--- Potential is not meaningless even if there's no resistance. As I previously said, there are different definitions of potential, first be clear which is what you are implying.
Running with this classical hydrostatic-esque model, what then determines the propagation speed of a voltage "signal"? In hydrostatics/dynamics the speed of pressure propagation is a relatively straightforward concept.
--- Voltage signal propagation and actual charge propagation are two different things. If you are interested in the former, you just need some exposure on the Electromagnetic Wave theory. Tranmission LIne Waveguides are good places to work. Only in THAT context does the SIGNAL propagation by CHAIN reactions makes sense. In a conductor where charge flow is necessary to charge a capacitor at the output (like in a CMOS circuit) things DO NOT MOVE at the speed of light. That's why your computer STILL runs at 3 GHz at 1V supply voltage.
I'm imagining that the potential applied at one terminal of the circuit pushes on the first charge carriers, which then push on charge carriers further inside the conductor. This idea seems a bit broken though, as it would result in a signal propagation speed that is some function of the mean free path etc. (I remember someone mentioning that the propagation speed is the speed of light)
---> Mean free path and signal propagation at c are VERY different. See my comments above.
I guess a more indepth question I was trying to resolve is, what is the mechanism for the potential being applied to charge carriers at some arbitrary distance away from the terminals. Is it the same as the hydraulic analogy where pressure is applied to one end of a tube and is then distributed through the tube through particle interactions, or is it more complicated?
---> See this: https://nanohub.org/resources/5345
What makes current flow?
Thanks. I'll be sure to check out the links. I'm fairly sure my speculation here is wrong, so think of it more as an invitation for people to poke holes in my bad understanding of these concepts.
We're driving at resolving the fundamental issue here, which I guess in a nutshell is to do with what a voltage signal is, how it propagates through a conductor and how it relates to charges flowing.
I have heard many (contradictory) ideas to do with the role of impedance in the measurement of a voltage signal, so I'm just trying to sort it all out.