Difference Between Thin and Conductive charge configurations

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Discussion Overview

The discussion revolves around the differences between thin insulating and conductive charge configurations, particularly in the context of capacitors. Participants explore theoretical and practical implications of using insulating shells versus conductive shells in capacitor design.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • One participant questions whether there is a computational difference between a thin spherical insulating shell and a thin conductive shell.
  • Another participant argues that insulating shells would not function effectively as capacitors because incoming charge cannot move freely, unlike in conductive shells where charges can flow and fully charge the surfaces.
  • A different viewpoint suggests that if a charge is uniformly distributed on thin insulating spheres, it raises questions about capacitance, despite practical charging issues.
  • One participant acknowledges that while an insulating configuration may have capacitance, it would not function as a workable capacitor without satisfying the necessary voltage/current relationship.

Areas of Agreement / Disagreement

Participants express differing views on the functionality of insulating versus conductive shells in capacitors, indicating that the discussion remains unresolved with multiple competing perspectives.

Contextual Notes

Participants highlight limitations regarding the practicality of charging insulating shells and the definitions of capacitance, which may depend on specific conditions and assumptions.

Rawrzz
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Difference Between "Thin" and "Conductive" charge configurations

Is there any difference computationally between say a thin spherical insulating shell and a thin conductive shell ?

Can you create a capacitor with two thin insulating shells, one smaller than the other ?

I see most textbooks explicitly say that capacitors must be conductors. Is this so ?
 
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The charge enters the capacitor from outside - with an insulator the incoming charge is stuck in one spot, so it would make a lousy capacitor. With conducting surfaces source charges can flow so that the entire surface is charged (both plates/spheres).

The region between the conductors is the insulator; the charges on the plates induce small movements in the molecules of the conductor - they "polarize" the material, but no charge moves more than a few nanometers.
 
Say a charge is already uniformly distributed on the thin spheres. Can you talk about capacitance then ? I realize that it is the practicality of charging that is the problem, but textbooks talk about uniform charge on insulators all the time.
 

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