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Homework Help: Question about potentials

  1. Nov 16, 2005 #1
    Can someone just confirm the following:

    Change in potential energy of a charge, for example caused by moving two negative charges together is equal to the work done:

    Work done = Force x Distance

    = -qE * ∆X (Where E is electric field strength)

    = -qE∆X

    = -q∆V

    Which therefore is a different quantity to the electric potential we know as simply Volts, which is (Work Done)/(q). I am fine actually using these different values in equations and the like, I would just like more information about what it all means. Is electric potential (Volts) simply a measure of Volts per unit charge? Or is it more complex than that? Probably a silly question really, but just like to be clear about these things. :smile:
  2. jcsd
  3. Nov 16, 2005 #2

    Tom Mattson

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    Exactly. The units also bear this out: 1V=1 J/C.

    I think the thing you are missing is that "electric potential" and "electric potential energy" are two different things, and they must not be interchanged. The former is measured in volts, and the latter is measured in Joules.
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