A question about Volume charge density and electrostatic equilibrium

AI Thread Summary
Volume charge density refers to the distribution of charge in a three-dimensional space, measured in C/m^3, while electrostatic equilibrium indicates that a conductor's charge resides solely on its surface. The discussion highlights that in practical scenarios, especially with non-perfect conductors, charges will rearrange to neutralize any internal electric fields, making volume charge density a theoretical concept. Even in lossy materials, charges will eventually move to the surface, eliminating internal fields over time. The conversation concludes that volume charge density does not necessarily imply uniform distribution, as it can vary at different points within a material. Understanding these concepts is crucial for grasping electrostatics in real-world applications.
Lanza52
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The concept of volume charge density is an even distribution of charge over a three dimensional area. C/m^3. However, the concept of electrostatic equilibrium says that all of a conductors charge lies on the surface of the conductor.

The existence of one seems, to me at least, to render the other pointless... Anything less then a perfect non-conductor would nearly instantly rearrange the charge towards the surface. So a volume charge density is a purely theoretical construct that will never exist. So any application of it is just in practice to demonstrate the math.

Am I missing something?
 
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Most materials are not perfect conductors.
 
The question is even it is not a perfect conductor...even a lossy material, as long as electrons can flow, any electric field inside the material will cause the electrons(charges) to flow and neutralize the field.

This is like you put a potential across a high value resistor ( say 10ee12 ohm), the moment you remove the voltage source, the potential across the resistor will immediately goes to zero. The resistor will not maintain the voltage ( field ) across by itself, electrons will stop flowing and no field is left.

For dielectric with very low conductance, it might take longer time for the charge to move to neutralize the internal field, but it will eventually.

This is actually a very good question.
To the OP, volume charge density do not imply even distribution. Charge density can vary from point to point inside.
 
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