I have a problem that I have encountered during research.(adsbygoogle = window.adsbygoogle || []).push({});

The setup for this scenario is that I am placing two contacts on top of a piece of diamond. What I need to be able to do is calculate the Electric Field at a point within the diamond when I apply a voltage to the contact. The point of interest is in between the two contacts but below them (as shown in the crude image I have made.)

Some of the things I am confused about

1. How are the charges accumulated on these contacts? In order for there to be an Electric Field at point P the charges can't only accumulate on the inside of the plate.

2. How would I calculate the total charge on the capacitor?

In order to simplify the problem I assume that we are finding the value of the Electric Field for a P close to the center of the contacts, meaning that the x-axis will not play a role in my calculation. So I need to be able to calculate the Electric Field contribution due to a cross sectional area, like shown below

However if I am taking a cross sectional area, the middle of this cross section can't have an accumulated charge only the edges can. I reasoned this because if we were to translate it back to the total volume, having a charge across the cross section would mean that the charges were spread out through the volume meanwhile the charges should be accumulating on the surface only.

Assuming this is correct I need to find a line charge density ρL. In order to do this I need to know what the total charge would be. I am unsure of using the general parallel plate capacitor formula Q = CV.

Secondly I am not sure how the sides will actually contribute to the Electric field at point P. It seems as though only the bottom of the plate will contribute to the Electric Field at that point.

One of the researchers I asked said that we can assume each side of the contact accumulates the same charge in order to simplify the problem but I am still unsure of the whole setup.

If you can help I'd appreciate it very much. I can also show any mathematical related work I have done

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# How to calculate the Electric Field due to Capacitors?

Have something to add?

Draft saved
Draft deleted

Loading...

**Physics Forums | Science Articles, Homework Help, Discussion**