I'm trying to teach myself polarization and dielectrics by doing problems, but it's not going as well as I'd hoped. Here's the first problem that I got stuck on:(adsbygoogle = window.adsbygoogle || []).push({});

A round dielectric disc of radius R isI thought that since the disc is polarized along its plane, there would be a charge density [tex]\sigma[/tex] on one half of it, and a charge density of [tex]-\sigma[/tex] on the other half of it. I wasn't sure if [tex]\sigma = P[/tex], but I set them equal anyway. I also wasn't sure if [tex]\sigma[/tex] is uniform along each half-surface, but I did that anyway. Then I thought that a uniform polarization vector means that the whole surface is charged up unformly, which means no net electric field at the center.staticallypolarized so that it gains the uniform polarizationP, with the vector P lying in the plane of the disc. Find the strength E of the electric field at the center of the disc if d << R.

I realize this is going to sound silly, but I have no idea how I'm supposed to solve this problem. Where am I supposed to start?

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# A Polarization Problem

Can you offer guidance or do you also need help?

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