# Question: electric field within insulator

1. Jul 7, 2009

### delis16

I am working on a research project in which i need to create a uniform electric field inside of a tube. I am using a glass tube and wrapping copper tape rings on the outside of the tube. The copper tape is charged to create an electric field. My question is whether or not the field will be present inside of the glass tube. Can electric field lines pass through an insulator and if so is the field any different than if the insulator wasn't there?

2. Jul 7, 2009

### bp_psy

The electric field lines would can pass trough an insulator and be somewhat changed(see dielectrics).
http://en.wikipedia.org/wiki/Dielectrics

The field will be 0 inside the tube. But not because the field lines are stopped by the insulator but because of Gauss law.
The simplest way to produce a uniform electric field is to use two charged parallel plates. A basic capacitor.

Wait what kind of research are you planing to do if you have so limited knowledge? Take care.

3. Jul 9, 2009

### qais97

First of all the air is insulator and the electric field can pass through it!!
I think he is working with discharge system.
If you need the mapping of electric field lines for such system, I will try to look to the equations for that.