I was wondering about some basic concepts of electromagnetism. Firstly, resistance is kind of like the measure of obstruction in a conducting material; right? So maybe the atomic properties of the conducting material are such that the current of electrons gets obstructed and ends up colliding with stuff in the way and as a result it generates all sorts of forms of energy. Is that right? Something else I was wondering is how does the dimensions of a conducting wire relate to how much heat it can dissipate. Before it starts melting, of course. I tried searching for it but I didn't have any luck. I found an article on joule heating which talks about the amount of heat generated by a certain current going through a conductor with a certain resistivity (P = RI2). I don't even know if what I understood from the article is correct. Anyway, if I double the external area of a piece of conducting wire. Will it be able to dissipate twice the amount of heat?