Insulator and conductor with electrostatic problems

AI Thread Summary
The distinction between conductors and insulators in electrostatic problems lies in their behavior in electric fields. In conductors, the electric field is always zero when in electrostatic equilibrium, as charges redistribute to cancel any internal fields. Conversely, insulators can have non-zero electric fields within them, allowing for polarization but no free current flow. The classification of materials as conductors or insulators is somewhat arbitrary, as all substances exhibit some level of conductivity depending on the voltage and current applied. Understanding these differences is crucial for applying Gauss's law and analyzing electrostatic scenarios effectively.
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I was wondering, what is the distinction made with problems involving either conductors or insulators with electrostatic problems.

Is it that the electric field in an insulator doesn't have to be zero, whereas the electric field in a conductor is always 0?
 
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That's what experiments have shown and which were the basis for Gauss's law or the equivalent Coulomb's law.
 
A conductor is an object in which a current will flow for as long as an electric field is present inside the object. From which of course follows that if no current is flowing inside a conductor there can't be an electric field there.
However in practice every substance is at least slightly conductive. So where you draw the line between conductor and insulator is arbitrary and depends on what kind of voltage and current you are working with.
 
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