Does there exist any electric field inside a charged conductor?

In summary, the lack of an electric field is the condition for the static state in a conductor. However, there can still exist an electric field inside a conductor, which is proportional to the current density according to Ohm's Law. On the atomic scale, there are always significant electric fields, but they average out. In electrostatics, all fields are assumed to be time independent and all current densities are assumed to be vanishing. In a conductor, the electric field must vanish according to Ohm's Law and the definition of electrostatics.
  • #1
Anindya Mondal
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We know that there exists no electric field inside a conductor. But while calculating drift velocity of electrons inside an electric conductor, why do we consider the electrons are present inside the charged conductor?
 
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  • #2
Anindya Mondal said:
We know that there exists no electric field inside a conductor.
There certainly can exist an electric field inside a conductor. The electric field is proportional to the current density for ordinary conductors. This is known as Ohm's law
 
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  • #3
Is it electric field or electric current?
 
  • #4
Anindya Mondal said:
Is it electric field or electric current?
Both. The electric field drives the electric current.
 
  • #5
What you're referring to is probably what you get told in electrostatics at first, but the lack of an electric field is actually the condition for the static state, it can exist and as mentioned here causes a current to flow, this is now electrodynamics
 
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  • #6
On the atomic scale there are always significant electric fields but these average out.
 
  • #7
gau55 said:
What you're referring to is probably what you get told in electrostatics at first, but the lack of an electric field is actually the condition for the static state, it can exist and as mentioned here causes a current to flow, this is now electrodynamics
Yeah, I refer to electrostatics
 
  • #8
In electrostatics by definition you assume that all fields are time independent and that all current densities are vanishing, ##\vec{j}=0##. Now you have (in non-relativistic approximation) ##\vec{j}=\sigma \vec{E}##, where ##\sigma## is the electric conductivity of your medium. For a conductor ##\sigma \neq 0##, which implies that ##\vec{E}=0##, because in the electrostatic case you have by definition ##\vec{j}=0##.
 
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  • #9
vanhees71 said:
In electrostatics by definition you assume that all fields are time independent and that all current densities are vanishing, ##\vec{j}=0##. Now you have (in non-relativistic approximation) ##\vec{j}=\sigma \vec{E}##, where ##\sigma## is the electric conductivity of your medium. For a conductor ##\sigma \neq 0##, which implies that ##\vec{E}=0##, because in the electrostatic case you have by definition ##\vec{j}=0##.
I can't understand, please be elaborate.
 
  • #10
What don't you understand? It's very simple. In electrostatics by definition the current density vanishes. In a conductor, according to Ohm's Law, the current density is proportional to the electric field and thus the electric field must vanish within the conductor. I don't know, how I can this elaborate more.
 

1. What is a charged conductor?

A charged conductor is a material or object that has an excess of either positive or negative electric charge. This charge is distributed throughout the material, creating an electric field around it.

2. Why is there an electric field inside a charged conductor?

When a conductor is charged, the excess charge on its surface creates an electric field inside the material. This electric field is necessary to maintain the equilibrium of charges on the surface of the conductor.

3. How is the electric field inside a charged conductor distributed?

The electric field inside a charged conductor is distributed evenly throughout the material. This means that the value of the electric field is the same at every point inside the conductor.

4. Can the electric field inside a charged conductor be changed?

Yes, the electric field inside a charged conductor can be changed by altering the amount of charge on the conductor. Adding or removing charge will change the strength of the electric field inside the conductor.

5. Is the electric field inside a charged conductor affected by the shape or size of the conductor?

No, the electric field inside a charged conductor is independent of the shape or size of the conductor. As long as the conductor is charged, the strength and distribution of the electric field inside it will remain the same.

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