1. The problem statement, all variables and given/known data Consider a simple circuit that looks like a rectangle (the cables), with 4.5 V attached on the bottom. The electrons are travelling from - to +, let's say I1 = 10A, which means they have an average velocity v1. Now put a 1kOhm resistance near the + side of the battery. I2 = 4.5mA anywhere in the circuit. My question is, how the hell does the electron that starts from the - end of the battery know that it shouldn't be travelling as fast? Isn't the E-field the same? 2. Relevant equations None that I can think of. 3. The attempt at a solution It's ready a theoretical question so I don't have an attempt. I know that they have to travel slower, because if not, they would clutter together at the resistance, and there's some law that doesn't allow it, I forget which (one of Maxwell's). I've always seen the potentials of a circuit represented by water falling down, so I tried applying the same here. Without the resistance = water falling in a tube, with a pump bringing it back up. With the resistance = near the bottom, make the tube really narrow, then after a few feet back to normal again. Applying what happens in the circuit in this situation, the water should start falling much slower than before; This can only be if the pump is pumping it slower. So does this mean that in the circuit, the battery's voltage is pumping the electrons slower or something like that? Thanks for any help!