Gauss's Law Problem: General than Coulomb's Law?

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    Gauss's law Law
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Discussion Overview

The discussion revolves around the comparison between Gauss's Law and Coulomb's Law, particularly in the context of their applicability to moving charges. Participants explore the theoretical implications of both laws and their relationship to electromagnetic fields.

Discussion Character

  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant states that Gauss's Law is more general than Coulomb's Law and can be applied to moving charges regardless of their velocities or accelerations.
  • Another participant argues that Coulomb's Law is not applicable to moving charges and that the Lienard-Wiechert potentials must be used instead, while noting that Gauss's Law still applies as div E = 4πρ in all cases.
  • A different viewpoint suggests that even when charges are in motion, Gauss's Law holds because the magnetic flux out of a closed surface is zero, and the electric flux remains relevant.
  • Another participant emphasizes that the changing nature of the magnetic field due to moving charges affects the curl of E, indicating that while Coulomb's Law fails, Gauss's Law remains valid since div E is unchanged.

Areas of Agreement / Disagreement

Participants express differing views on the applicability of Gauss's Law versus Coulomb's Law, with no consensus reached on the implications of moving charges for these laws.

Contextual Notes

Participants reference the need for different mathematical treatments when dealing with moving charges, indicating that assumptions about charge motion and field behavior are critical to the discussion.

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?
 
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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).
 
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.
 
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.
 

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