Electrodynamics regarding volume charge density behavior

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Discussion Overview

The discussion revolves around the behavior of volume charge density in electrodynamics, particularly focusing on the differences between constant and non-constant charge densities. Participants explore concepts related to electrostatics and the application of Dirac delta functions in these contexts.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification

Main Points Raised

  • Some participants suggest that if the charge density is constant, the discussion pertains to electrostatics, where a static charge density is typically modeled as a continuum of finite total charge in a finite space.
  • Others mention the potential use of Dirac delta functions to model isolated charge densities, although they note that this is not essential for electrostatics.
  • A participant requests further elaboration on the topic, indicating a need for deeper understanding.
  • Another participant points out that the original question lacks specificity and suggests that the subject is extensive, referencing the existence of large books on the topic.
  • A later reply quotes a passage from Griffiths regarding the application of Gauss’s law at the surface of a dielectric, expressing confusion about the implications of the statement.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus, as there are varying interpretations of charge density behavior and the application of related laws, with some expressing confusion and seeking clarification.

Contextual Notes

The discussion highlights limitations in understanding specific concepts related to charge density and the application of Gauss's law, as well as the dependence on definitions and the complexity of the subject matter.

AHSAN MUJTABA
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In this explanation we need to involve the Dirac delta functions(maybe) but I clearly have a difficulty in understanding it can some one explain me the whole concept of constant or non constant volume charge density.
 
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If this is a constant charge density, then technically we are discussing electrostatics. In some ways the simplest model for an isolated "small {in physical extent) charge density uses the Dirac ##\delta ## function but it is not essential for the electrostatics.
A static charge density is typically a continuum of finite total charge in a finite space that is constant is time.
 
Would you please elaborate a bit please?
 
Your question needs to be more specific. There are very large books on this subject!
 
Okay being specific I want to quote the following paragraph from Griffiths,
"We cannot apply Gauss’s law precisely at the surface of a dielectric, for here ##\rho_b## blows up, taking the divergence of E with it."
I don't really understand the meaning of it an explanation is needed.
 

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