IIT JEE , AIEEE Forum - Physics , Electricity

aamil4u

In our physics class sir said that an insulator [bad conductor] allows an electric field to pass through it but a conductor does not

Why is that?

Can anyone please explain the actual phenomenon and the reasons behind them?

No mathematical explanations required

rahulkarmakar14

If an electric field did exist beneath the surface of a conductor (and inside of it), then the electric field would exert a force on all electrons that were present there. This net force would begin to accelerate and move these electrons. But objects at electrostatic equilibrium have no further motion of charge about the surface. So if this were to occur, then the original claim that the object was at electrostatic equilibrium would be a false claim. If the electrons within a conductor have assumed an equilibrium state, then the net force upon those electrons is zero. The electric field lines either begin or end upon a charge and in the case of a conductor, the charge exists solely upon its outer surface.

rahulkarmakar14

In contrast to conductors, insulators are materials which impede the free flow of electrons from atom to atom and molecule to molecule. If charge is transferred to an insulator at a given location, the excess charge will remain at the initial location of charging. The particles of the insulator do not permit the free flow of electrons; subsequently charge is seldom distributed evenly across the surface of an insulator.

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