Now, this question may be incredibly stupid, but it has been bothering me nonetheless. I figure you guys can set me straight really easily. Say you have a basic circuit loop as shown in the picture. Ohm's law: [tex] V = RI [/tex] Now, according to a textbook I'm reading right now, "By Ohm's law, there is no voltage across an ideal (i.e. zero-resistance) wire regardless of the current flowing through it." I'm just wondering what the meaning of that statement is. Yeah, sure, obviously: [tex] V = 0I = 0 [/tex] But when I look at that picture, here's how I see it: there is definitely a potential difference between points A and B, because they are at either end of the battery. But these points are also the two ends of the wire that makes up the loop! So how could there possibly not be a potential difference across the wire?! And if there weren't, why would there be any current at all? Aren't the electrons moving from a point of high potential to low potential, gaining KE along the way? So there must be a voltage across the wire.