How electric circuits really work

[bobkolker]

There are "levels" of understanding physical phenomena. If you want to understand an electric circuit at the level of atomic physics then you have quite a job ahead of you. Even if you take the model of a electron as a small charged classical mass, the detailed physics of an electrical circuit is not simple. For example, if the electric field accelerating electrons was the only force on an electron then it should accelerate while in the wire and have greater velocity at the "downstream" end of the wire than at the upstream end of the wire.

You should seek a level of understanding that matches what you want to do. If you want to build everyday electric circuits then you don't need to understand what's going on at the atomic level - and maybe nobody really understands the atomic level. If you want to design vacuum tubes, or design radio antennas, you need a different level of understanding.

The easiest way I have found to understand energy flow in an electric circuit is by means of Poynting vectors. The electron move in the wire (slowly) because of potential difference. The electrons have the field E and the motion produces the magnetic field S. The Poynting vector E x S tells you the magnitude of the energy flow and the direction. BTW the energy flows from the battery to the resistance through -space-., not just along the wire. The "garden hose" model of energy flow in a circuit is all wrong. Think about it. When you switch on a light it lights up nearly instantly. If one had to wait for electrons to travel to the lightbulb from the battery it would take hours.

 

[sophiecentaur]

lots of charged particles moving in a stream IS a current.

Of course it is but how does that help when you are considering the right component to use in an electric circuit. And what is the nature of these charged particles that you are using in your model?
People forget that ALL the basics of Electrical Engineering were established long before the electron had been discovered. It is a deluded idea that electrons actually help in elementary electrical theory. I speak from experience. At School, we were not encouraged to bring electrons into our electrical basics until we knew enough about them to make valid connections. It was a massive help for me because I didn't waste time with half arsed analogies, which is all you can get from the electrons that kids are told about in School these days.