conductor or insulator?
SIR, I want to ask you 1 question. Whys is it that Earth some times behaves like a conductor and some times behaves like a dielectric. Please answer this question. I’m a student of telecommunication, from Pakistan. REPLY My work experience is with the magnetic field of Earth in space, so please check what I write with someone more experienced! Also, your question is not very specific–one must guess what you mean each time you write “sometimes.” Still, let me try. Sometimes the Earth is like a conductor–for instance, when you ground an instrument by running a wire from it to pipes in the ground. That is probably ionic conductivity–caused because earth usually has SOME water in it, coating its grains of clay or sand. That water is never pure (like distilled water) but always has at least some salt dissolved in it, and maybe other “electrolytes” as well. Such dissolved molecules break up into electrically charged components, which can conduct electric charge (see http://www.phy6.org/Ed
