Negative Voltage: Understanding How Current Travels

AI Thread Summary
Negative voltage indicates that the potential at the negative terminal can be higher than that at the positive terminal, leading to current flowing from the negative to the positive terminal, contrary to conventional flow. In the context of the Millikan Oil Drop Experiment, the negative voltage observed does not change the fundamental principle that current flows from higher to lower potential. If the negative terminal is considered the reference point, it can indeed have a higher potential, allowing current to flow in the opposite direction. The discussion highlights the importance of understanding voltage references and potential differences in electrical circuits. Overall, negative voltage can alter the expected direction of current flow based on the defined reference points.
gbaby370
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I just completed a problem regarding a Millikan Oil Drop Experiment. I ended up with a negative voltage in the solution.

I am just trying to understand negative voltage. Does it mean that the current will travel from - to + instead of the conventional + to -?
 
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gbaby370 said:
I just completed a problem regarding a Millikan Oil Drop Experiment. I ended up with a negative voltage in the solution.

I am just trying to understand negative voltage. Does it mean that the current will travel from - to + instead of the conventional + to -?

yes it does
 
phinds said:
yes it does

Umm.. I don't think so. Why would it do that? Conventionally signed current will always flow from the higher (more +ve) potential to the lower.
 
If the "-" represents the ground or reference then I believe the "+" can have any potential difference whether positive or negative. In such a case though the "-" terminal will have the higher potential and so conventional current will run from it to the "+" terminal.
 
Waterfox said:
If the "-" represents the ground or reference then I believe the "+" can have any potential difference whether positive or negative. In such a case though the "-" terminal will have the higher potential and so conventional current will run from it to the "+" terminal.

Yeah, that's what I meant, but my simple "yes" was a bit misleading, as haruspex correctly pointed out.
 

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