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I'm sure we have all seen the frequent questions from students who don't understand the difference between potential and voltage in a circuit. They seem to think that zero voltage has physical significance. Even using the phrase "voltage drop" is not suffienct, because they say, "What happens when it drops to zero," leading to the concept that voltage is a consumable.
Of course, EEs use the convenience of assigning some point in the circuit the arbitrary value of 0, then expressing everything relative to that. I suspect that simplification in language contributes to the students misunderstanding. In the example circuit below, I would strictly refrain from saying ##V_A##, ##V_B##, ... Instead I would only mention voltage with respect to two places in the circuit. ##V_{AG}## ##V_{BG}##. I view that as a tiny tweak in the use of language by the teachers.
Verbally, I would never mention "voltage .. " without saying "voltage with respect to ..."
But I have been out of school for many years. Perhaps modern teachers already do it that way. Is that so?
Of course, EEs use the convenience of assigning some point in the circuit the arbitrary value of 0, then expressing everything relative to that. I suspect that simplification in language contributes to the students misunderstanding. In the example circuit below, I would strictly refrain from saying ##V_A##, ##V_B##, ... Instead I would only mention voltage with respect to two places in the circuit. ##V_{AG}## ##V_{BG}##. I view that as a tiny tweak in the use of language by the teachers.
Verbally, I would never mention "voltage .. " without saying "voltage with respect to ..."
But I have been out of school for many years. Perhaps modern teachers already do it that way. Is that so?