[thehappypm]

Ah, transmission lines. I studied these for far too long. It’s how I wound up in software!

Things like Ohm’s law are great tools for understanding circuits. However, the underlying forces that derive these equations are a bit lower level, and relate to charged particles creating electric fields. Every electron flowing is because there’s a net force on it, coming from an electric field caused by other electrons, protons, or magnetic interactions.

Electric fields are kind of hairy to use directly, and a much more easy-to-use concept is voltage. Voltage abstracts the field concept away, and tells you about how much energy will be expended moving charge around.

Turn a circuit on, what happens isn’t that the whole circuit works in lock step. First some charges near the power source will move, inducing new fields that propagate as a wave.