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Relationship between electric forces

  1. Sep 11, 2004 #1
    I am wondering if there is some way for the force between two charges (calculated by Coloumb's law) and the force applied by a field on a charge.

    Thanks in advance
  2. jcsd
  3. Sep 11, 2004 #2


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    Could you rephrase your question?
  4. Sep 11, 2004 #3

    What I am trying to do is find out how the electric potential of a radial field equation is derived. I have found a derivation by using Coulomb's Law and the equations for electric force, work etc however I do not understand the equation completely. This is because I do not know if the force between two charges (Coulomb's Law) and the force exerted on a charge by a field can be compared.

  5. Sep 11, 2004 #4


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    They are equivalent. The force acting on a charge is related to the electric field by [itex]\vec F = q \vec E[/itex]. In fact, that's how electric fields were defined.
  6. Sep 12, 2004 #5
    Take Coulombs's law, separate a q, call the rest an electric field E defined by [tex]E = \frac{kQ}{r^2}[/tex].

    That's pretty much all there is to it. Once E is defined in this way, it paves the way for all of electrostatics. The same E then contributes to describe Maxwell's electromagnetic theory in its entirety.
    Last edited by a moderator: Sep 12, 2004
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