# Homework Help: Work done by electric force on a point charge in a cylinder?

1. Feb 10, 2014

### cesaravila

1. The problem statement, all variables and given/known data

A point charge q is moved inside a hollow charged cylinder of radius R. The initial point A is a distance (3/4)R from the center and the final point B is at the center of the sphere. How much work is done by the electric force in this case?

2. The attempt at a solution

I am thinking that no work is done because its equipotential, but I am not certain its equipotential.

2. Feb 10, 2014

### SammyS

Staff Emeritus
Hello cesaravila. Welcome to PF !

In one place you mention a cylinder. In another you mention a sphere.

Which is it ?

3. Feb 10, 2014

### cesaravila

It is a cylinder. The final point B is at the center of the cylinder.

4. Feb 10, 2014

### haruspex

Is the cylinder a conductor? A uniformly charged non-conductor? Any mention of the charge or charge density?

5. Feb 11, 2014

### cesaravila

It is a charged insulator.

6. Feb 11, 2014

### haruspex

Assuming it is a uniform charge and a long cylinder, I agree the potential should be constant inside.