I watched a few videos on conductors in electrostatic equilibrium and all I understood is that the charges stick to the surface of the conductor. So does that mean if I have a copper wire with no current going through it, the electrons will stick to the surface of the wire? Please help me understand this concept and how it is used. I don't understand the idea of it. Examples may help.

Also I have another question, isn't magnetism coming from electric fiels and electric forces? Is there any difference between them and also how is a ferromagnet attracted to the north and south pole. I mean, if we say north is positive and south is negative, then the ferromagnets are charged with something magical?


You're close but just not quite there. I recommend some Walter Lewin lectures (I watched them just a few weeks ago when being lectured on it myself).

The first concept is that if you have a net charge then the electrons (assuming it is a negative charge) will distribute themselves on the surface of the conductor. This is an interesting property of charged conductors and you might ask yourself why? Well this is somewhat easier explained using gauss law, (if you don't know what that is a simpler although maybe less convincing explanation is that the electrons will distribute themselves so they're all as far away from each-other as possible which puts them all at the surface). Now one of my favourite universal field equations. Gauss law. Firstly I want to emphasise the point that inside a charged conductor there is no E field. If there was the charges would move until they were in equilibrium. Therefore if we draw a gaussian surface below the surface gauss law tells us that if theres no E field inside the conductor there can be no net charge in the conductor. Thus we conclude all the charge must be on the surface. (Note this does not tell us how it is distributed, merely that it is there).

Now onto your second question. Magnetic forces are derived from electric fields and MOVING electric charges. This comes from special relativity. The basic intuition is there but the mathematical rigour to describe such things is a little beyond me (see me next year). Id hazard a guess that it may be beyond your current self to so I wouldn't worry about this.

Asking why a ferromagnet is attracted to a north pole is like asking why an electric field is attracted to a negative charge. We don't really know the why, we just set up a system to describe it and that results in us defining such things as a ferromagnet is attracted to the north pole of a magnet. And no ferromagnets are not charged with anything special. They have a magnetic property associated with them due to the intrinsic magnetic spins of their electrons


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