This might be kind of weird, but how exactly does an AC signal flow in a wire? Suppose we have a copper wire with an AC signal (sine wave) flowing through it. Does it flow through it in the sense that if we suddenly freezed the signal and you took different chunks of the wire would they be at a different potential? Or does the potential of the entire wire vary such that when the particular potentials are plotted as a function of time they form the sine wave? (ie, at one point in time the potential of the entire wire is at 120 Volts and then a microsecond later it’s at 119.99 Volts, etc.)

I am having difficulty articulating this so if it doesn’t make sense then please let me know. Thanks guys.