Say a circuit has a 9V DC supply, a 2 ohm resistor in series with it and also a parallel combination of two 1 ohm resistors in series with it. So a simple series-parallel circuit. What I don't understand is why the voltage drop across the 2 ohm resistor isn't 6V and the voltage drop across both parallel resistors isn't 3V from a physics perspective? I think about it from the perspective of an electron, the electron effectively must traverse through 2 ohms and select one path of 1 ohm, and so it should use 2/3 of it's energy across the 2 ohms and the other third across the 1 ohm from my thinking. However, I know this is not true because when we simplify the parallel combination to 0.5ohms in series with the 2 ohms the voltage division changes completely. I'm aware the voltage divider formula relies on their being equal currents in resistor branches, but from an energy perspective it doesn't make sense to me as to why it doesn't work. I thank anyone in advance.