How Electricity Actually Works

pingstonsmile, there is a YouTube channel called Kathy Loves Physics & History that goes into such things as why most of the world uses 50 Hz 220V and the US and some others use 60 Hz 120V.

All of it is very interesting and she is writing a book on it all...and how it all came about since the early days of electricity. 

@jea48 

In all of the books of electronics and electrical engineering, the electric signal through the conductor is the ordered motion of electrons

I think it’s great he made that video and got people like me thinking, even though it was a little misleading. In his follow up video he makes it clear that the bulb will by no means come on full strength right away, and that the early effect will still occur even if the circuit is open somewhere way out there in space. Once that was made clear I was reminded of when I first learned about transformers, how they could transfer power without any direct physical connection between the conductors. I was amazed at that, but also disappointed that they tended to be noisy and inefficient.

On another controversial claim seen in a YouTube video, the notion that you can make a wind powered car that can go down wind faster than the wind still messes with my head.

On another controversial claim seen in a YouTube video, the notion that you can make a wind powered car that can go down wind faster than the wind still messes with my head.

My understanding is there are two effective forces, one is the wind pushing, but the other, less obvious, is the wind "pulling"  (though still pushing). Sail boats can also go much faster than the wind.

I didn't spend a lot of time looking at this, but appears to be Bernoulli force, just like an airplane. The wind travels faster over the sail, which causes low pressure, so you have additional force acting on the sail which makes the boat go faster.

In the ground car, the low pressure is created by the propeller. The wind does not spin the propeller, it moves the car whose wheels are connected to the propeller causing it to spin.

czarivey

4,837 posts

05-02-2022 at 11:37am

@jea48

In all of the books of electronics and electrical engineering, the electric signal through the conductor is the ordered motion of electrons

@czarivey

This guy wrote a few books too...

Here’s an article he wrote a few years ago.

What is Electronics - Ralph Morrison

Here is an excerpt from the article:

Storing or moving energy.

There is a common misconception that signals are carried in conductors. Somehow this association crosses over to the idea that conductors carry both signals and energy. A few simple calculations can show that this is a false idea. Consider a 50-ohm transmission line carrying a 5-volt logic signal. The initial current at switch closure is 500 mA. A typical trace is a a gram-mole of copper that has 6 x 10²³ copper atoms (Avogadro’s number). Each atom can contribute one electron to current flow. Knowing the charge on an electron makes it easy to show that the average electron velocity for 500 mA is a few centimeters per second. What is even more interesting is that only a trillion electrons are involved in this current flow. This means that only one electron in a trillion carries the current. This also says that the magnetic field that moves energy is not located in the conductors. The only explanation that makes sense is that energy in the magnetic field must be located in the space between two conductors. Conductors end up directing energy flow - not carrying the energy.

Here is another article written by the Late Ralph Morrison: