Electric field between two electrodes with insulator/conductor between.

In summary, the conversation discusses the investigation of equipotential lines and electric field lines between two electrodes with conductors and insulators. It explains how the equipotential lines bulge around the conducting cylinder and curve towards it with an insulator between the electrodes. It also discusses the effects of induced charges and polarization on the electric field within and outside the conductor and insulator.
  • #1
Ryland
1
0
Hi,
I don't have a set question that needs answering, I'm just a little confused and need some clarifying if that's possible..

We've been investigating equipotentials and electric field lines between two electrodes with conductors and insulators between the electrodes.

With a conducting cylinder between the electrodes we got the equipotential lines sort of bulged around the cylinder and so the electric field lines pointed into the cylinder.
And with the insulator between we got the equipotentials curving towards the cylinder and the electric field lines curving around it.

I know that inside a conductor the electric field is zero, so does that mean on the edge is zero as well, so that's why the electric field lines hit the edge perpendicular?

but i don't really know why that happens with the insulator, is it just because electric field cannot go through an insulator so it 'bends' around the cylinder?

Any help or direction you can give me will be greatly appreciated.
Thanks.
 
Physics news on Phys.org
  • #2
hi i am also stuck with the same problem.I WILL EXPLAIN MY LOGIC.SO PLEASE BEAR WITH ME
CONDUCTOR.png


Let a charge 1C be given to plate A and equal -1C given to E.Now due to induction B will attain some -ve charge and D with an equal positive charge.Charges flow from D to B till magnitudes of charges on A,B,D,E become same
so now we have A=1C,B=-1C,D=1C,E=-1C
now let us assume the net electric field intensity is 0 somewere at C
so AC=(d+x),BC=x,CD=(l-x),CD=(d+l-x)

now field due to A on C=(K*1)/(d+x)^2 from A to C=[A]
B on C=(K*1)/(x)^2 from C to B=
D on C=(K*1)/(l-x)^2 from D to C=[D]
E on C=(K*1)/(d+l-x)^2 from C to E=[E]

therefore for electric field to be 0 at C

B+D-(A+E)=0
putting values

(k)/(x)^2+(K)/(l-x)^2=(K)/(d+x)^2+(K)/(d+l-x)^2

on solving for x you can obtain at what point field is 0. thank u

i have gave by reasoning.i don't think this should be wrong.but please if u can verify it will be good
 
  • #3
Ryland said:
Hi,
With a conducting cylinder between the electrodes we got the equipotential lines sort of bulged around the cylinder and so the electric field lines pointed into the cylinder.
And with the insulator between we got the equipotentials curving towards the cylinder and the electric field lines curving around it.

First of all, what exactly did you do to investigate the fields lines?

The field inside a conductor is zero. At the surface, the field is perpendicular (to the surface). The external field induces charges on the conductor, the field inside is zero and is perpendicular at the surface. The charges induced in the conductor produce their own field outside the conductor, which would slightly cancel the field outside, the field outside the conductor would increase from zero in conductor to its original value far from the conductor (or here, at the two electrodes. Also, the field need not be zero everywhere on the surface of the conductor). So you would have equipotential lines bulged around the conductor.

In case of the insulator, the field would just polarize the atoms. The field would be reduced inside the insulator, but not zero, & it would still be pointing in the same direction. There would be some surface charges due to the polarization, their field again very slightly cancels the field outside, leading to the equipotentials bending towards the cylinder.
 

FAQ: Electric field between two electrodes with insulator/conductor between.

1. What is an electric field?

An electric field is a physical field that surrounds a charged particle or object. It is a vector field, meaning it has both magnitude and direction, and is created by the presence of electric charge.

2. How is an electric field created between two electrodes?

An electric field is created between two electrodes when there is a difference in electric potential (voltage) between them. This creates a force that causes charged particles to move between the electrodes.

3. What role does an insulator play in the electric field between two electrodes?

An insulator acts as a barrier between two electrodes, preventing the flow of electric charge and reducing the strength of the electric field. It is a non-conductive material that does not allow electrons to move freely.

4. How does the presence of a conductor affect the electric field between two electrodes?

A conductor allows for the free flow of electrons, which can change the strength and direction of the electric field between two electrodes. This is because the presence of a conductor can redistribute the electric charge and create different pathways for the flow of electrons.

5. What factors affect the strength of the electric field between two electrodes?

The strength of the electric field between two electrodes is affected by the distance between the electrodes, the amount of charge on the electrodes, and the type of material between the electrodes (insulator or conductor). Additionally, the presence of other charged particles or objects in the vicinity can also affect the strength of the electric field.

Back
Top