Does there exist any electric field inside a charged conductor?

  • #1
Anindya Mondal
21
1
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?
 

Answers and Replies

  • #2
33,868
11,575
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
 
  • Like
Likes FactChecker
  • #3
Anindya Mondal
21
1
Is it electric field or electric current?
 
  • #4
nasu
Homework Helper
4,102
704
Is it electric field or electric current?
Both. The electric field drives the electric current.
 
  • #5
gau55
4
1
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
 
  • Like
Likes Anindya Mondal
  • #6
1,499
443
On the atomic scale there are always significant electric fields but these average out.
 
  • #7
Anindya Mondal
21
1
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
vanhees71
Science Advisor
Insights Author
Gold Member
2022 Award
22,472
13,400
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##.
 
  • #9
Anindya Mondal
21
1
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
vanhees71
Science Advisor
Insights Author
Gold Member
2022 Award
22,472
13,400
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.
 

Suggested for: Does there exist any electric field inside a charged conductor?

Replies
13
Views
536
Replies
14
Views
517
Replies
10
Views
480
Replies
44
Views
1K
Replies
5
Views
340
  • Last Post
Replies
6
Views
789
Replies
5
Views
588
Replies
12
Views
586
Top