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Negative Voltage vs. Negative Pressure

  1. Dec 22, 2006 #1
    Assume conservation of energy and conservation of charge for a system such that:




    What is "negative" voltage?


    I am doing the following right? Or is the relationship between negative voltage and negative pressure not this easy?

    Assume that the system of charged particles is not in equilibrium. Assume that the system is closed. The charges will clump irregularly. The spaces in between will have negative voltage. If we assume that these parts of the systems compose mostly of cations (e.g. H+), this means that energy in the gaps between the charge clumps is negative. The empty regions would have a negative pressure, because energy corresponds to pressure * volume.

    http://www.google.com/search?q="negative+voltage"+"negative+pressure" ;)
    Last edited: Dec 22, 2006
  2. jcsd
  3. Dec 22, 2006 #2


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    Your calculation of "voltage" (presumably, you mean electrostatic potential) is incorrect. And what does pressure have anything to do with this? No, negative energy does not mean negative pressure. Energy is only defined up to an arbitrary additive constant. I can always make the energy positive if I wish.
  4. Dec 22, 2006 #3
    When I said energy, what I really meant was pressure * volume. Should have clarified that. The point of the post was to ask/verify if negative changes in pressures are related to negative changes in voltage.
    Last edited: Dec 22, 2006
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