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Gauss's law problem

  1. Mar 1, 2007 #1

    Kolahal Bhattacharya

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    I read in Corson and Lorrain that Gauss's law is more gneral than Coulomb's law.It can even be applied to moving charges whatever be their velocities/accelerations.Can anyone explain this?
     
    Kolahal Bhattacharya, Mar 1, 2007
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  3. Mar 1, 2007 #2

    Meir Achuz

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    Coulomb's law cannot be applied to moving charges.
    The Lienard-Wiechert potentials have to be used.
    Since div E=4pi rho in all cases, Gauss's law still applies.
    However since the symmetry is lost, Gauss's law just gives the integral of E over a closed surface and can't be used to find E(r).
     
    Meir Achuz, Mar 1, 2007
  4. Mar 1, 2007 #3

    Kolahal Bhattacharya

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    Well,I found it in a text I mentioned.I think we may think this way:the charge inside the closed surface will be static or moving.Whatever the case,the fluxes are electric as well as magnetic.Gauss's law still holds because, magnetic flux out of a closed surface is zero.We do not find the B field when charges inside are in motion.
     
    Kolahal Bhattacharya, Mar 1, 2007
  5. Mar 2, 2007 #4

    gimel

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    This is clear if we look at the Maxwell Equations. The curl of E is no longer zero, for the particle is moving and that makes the B changing with time. Thus the Coloumb's Law fails but div E is unchanging and Gauss's Law holds.
     
    gimel, Mar 2, 2007
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