Why cant there be an electric field in a conductor?

In summary, according to Maxwell, there can't be an electric field in a conductor because the fields from each side of a point inside the conductor cancel out. However, in cases where the conductor is not at equilibrium, such as when there is a net force acting on the charge carriers, there can be an electric field in the conductor. This field is determined by Ohm's law and the material properties of the conductor.
  • #1
indigojoker
246
0
why can't there be an electric field in a conductor?
 
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  • #2
Because Maxwell said so!
Short answer is that the fields from each side of a point inside the conductor cancel out - long answer involves a bit of maths.
 
  • #3
I guess you are talking about a conductor at equilibrium. In this case the electric field in the conductor is 0 because otherwise the charge (which is mobile in a conductor) would be moving and there wouldn't be equilibrium any more.
 
  • #4
I guess you are talking about a conductor at equilibrium.

what other cases are there and why would there be an electric field in the conductor?
 
  • #5
indigojoker said:
what other cases are there and why would there be an electric field in the conductor?

If there is a net force acting on the charge carriers, the conductor isn't at equilibrium any more. This force could come from a voltage/current source or from a change in the magnetic flux in that circuit.
In this case the electric field in that conductor isn't 0 any more. It is given by Ohm's[/PLAIN] [Broken] law
 
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1. Why can't there be an electric field in a conductor?

According to Ohm's Law, in a perfect conductor, the electric field must be zero. This is because the electrons in a conductor are free to move and will immediately align themselves in a way that cancels out any external electric field.

2. How does the presence of free electrons in a conductor affect the electric field?

The presence of free electrons in a conductor allows for the easy flow of electricity, but it also means that any external electric field will be quickly neutralized. The electrons will move in response to the electric field, creating an opposing field that cancels it out.

3. Can there ever be an electric field in a conductor?

In theory, there can be a small electric field in a conductor if it is not a perfect conductor and has some resistance. However, this field would be extremely small and would dissipate quickly due to the movement of free electrons.

4. Why does the electric field in a conductor become zero when it reaches equilibrium?

When a conductor reaches equilibrium, the electric field becomes zero because the free electrons have evenly distributed themselves throughout the conductor. This creates a state of balance where there is no net movement of electrons, resulting in a zero electric field.

5. How does the absence of an electric field in a conductor affect its ability to conduct electricity?

In a conductor, the absence of an electric field does not affect its ability to conduct electricity. In fact, it is necessary for a conductor to have a zero electric field in order for electricity to flow freely through it. The presence of an electric field would disrupt the movement of free electrons and hinder the flow of electricity.

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