# How to calculate resistance between two electrodes filled with water

1. Dec 7, 2006

### guptasuryakant

Hello ,

Can someone from this group help me ,how to calculate resistance between two electrodes filled with water with a known conductivity solution.

In my case I have two experimental conditions. First there are two rectangular plates seperated with a gap of 30 mm.

In second case this is a cylindrical geometry Innner electrode dia is 10 mm. And outer electrode dia is 50 mm. In between water is filled with a conductivity of 500µ cm/cm.

If some one can answer atleast for one case it will be useful for me.

regards

2. Dec 7, 2006

### Staff: Mentor

For the rectangular case, the resistance is

$$R = \frac{\rho L}{A}$$

Where A is the crossectional area, and the resistivity is $$\rho$$

The calculation is similar for the cylindrical geometry, but you need to set up an integral to do it over small volume elements that approximate the rectangular situation.

3. Dec 7, 2006

4. Dec 7, 2006

### guptasuryakant

How I can put the value in place of resistivity