Well in that case it makes the gravity analogy look kind of stupid because there would need to be anti-people moving down the lift and up the runs because there are always both negative and positive charges moving in a circuit.

And, I won’t even mention the movement of “people” in a constant circle which would be impossible in a battery powered circuit…no wait, I just did.

No, In the copper wiring there is only one type of moving charge, the, in conventional current, positive electron 'people'. The people remain the same internally just like electrons do in a circuit. Negative and positive charges (or people using the lift on the right side or left side of the ski lift gravity analogy) is irrelevant to the transport of energy as long as we are consistent.

 

It's not clear to me.
What are these "difficulties" from not knowing about fields?

I know that fields exist wherever there are voltages and currents, but I seldom think about them (or much less use them) to understand most circuits or in doing circuit design, so why do the kids need to?

I've said this before and you tried to ridicule me because of it but my mental image of circuit operation is different from the mechanical ball current model. I seldom think about fields as distinct entities because it's automatic like riding a bicycle but it's an intrinsic view of electronic circuits is seems some people just don't have. It can't be explained to those, that I'm guessing, don't the IMO natural born ability or the necessity to build and see it.

 

Current that you measure with meters is from positive to negative. It's "charge".

This is where the water analogy falls apart somewhat. Nothing physical flows through the wires.
I might explain it as "bumping cars"

 

I know that fields exist wherever there are voltages and currents, but I seldom think about them (or much less use them) to understand most circuits or in doing circuit design, so why do the kids need to?

But you're already very familiar with the Ohmic model and have developed a working intuition for it. Consequently, it's useful for you to imagine that a voltage pushes electrons to form a current, but these words -- voltage, electrons, current -- are usually meaningless to a beginner. They won't be able to mentally picture a "voltage", but visualizing distance along a field gradient is within their intuition, e.g., by way of analogy with gravity.

 

I seldom think about fields as distinct entities because it's automatic like riding a bicycle but it's an intrinsic view of electronic circuits is seems some people just don't have.

I suspect they don't have it because they've internalized the "little balls of charge" model, which is incompatible with the field model. And this is why I advocate learning fields first, so that students don't get hung up on unphysical models.

 

Correct, the electrons are the field

So there's no such thing as an electron, only an electron field?
That makes no sense (but then that's typical of Quantum Mechanics).
So what they measuring when that talk about the mass and diameter of an electron?

 

This is where the water analogy falls apart somewhat. Nothing physical flows through the wires.

Electrons aren't physical?
I know they flow very slowly through wires, but they do flow.

You put a molecule of water into one end of a pipe and a molecule of water flows from the other end.
You put a electron into one end of a wire, and an electron comes out the other end.

 

I suspect they don't have it because they've internalized the "little balls of charge" model, which is incompatible with the field model. And this is why I advocate learning fields first, so that students don't get hung up on unphysical models.

I want the possible techs of tomorrow to be able to understand, at a simple level how things work on the devices they use. This requires and is not optional, a basic understanding of how fields integrate with modern circuits.
https://education.abc.net.au/web/zoom/science#touchscreen2
Touchscreen feature animation

Ever wondered how swiping your finger makes a touchscreen work? In this animation, see how invisible electric fields mess with your finger so your phone can pinpoint what you're touching.

https://www.abc.net.au/science/articles/2014/02/05/3937083.htm
Are we teaching electricity the wrong way around?

This qualitative explanation really works for a non-physicist like me. And not just because it does away with the waterfall analogy and current carrying energy misconceptions. Or because it's screaming out for a nice animation to explain it. (Note to self: apply for funding …).

It works for the same reason most good conceptual frameworks work: it's a simplified version of reality as physicists understand it. And a bonus — it makes clear the link between electricity and magnetism from the get-go, as well as the link between between charge, electromagnetic fields and energy.

That alone is worth its weight in conceptual gold.

 

So there's no such thing as an electron, only an electron field?
That makes no sense (but then that's typical of Quantum Mechanics).

Actually, it makes no physical sense to believe that an electron is a tiny ball. You're just used to thinking of them as such, but a century of physics has shown that belief to be untenable under scrutiny.

So what they measuring when that talk about the mass and diameter of an electron?

The mass of an electron is its energy, which is a field property. The "diameter" of an electron is an invented value, akin to the length-scale of its influence, which is useful to quantify in some applications.

 

Are we teaching electricity the wrong way around?

100% agree.

 

Current that you measure with meters is from positive to negative. It's "charge".

So if "charge" is current then what is voltage?

 

Current is the flow of charge.
Voltage is the measure of potential difference that provides the force to make charge flow.

 

I knew you were going to say that.

In my universe charge moves mass not itself.

 

it's an intrinsic view of electronic circuits is seems some people just don't have.

Then you can count me as one of those.
I know and understand fields but they don't usually come to mind unless I'm talking about RF circuits or transformers.
The model of a little round (charged) ball (which generates a field) works fine for me (even if the electron doesn't exist as a particle as bogosort stated).
Whether that field is really carrying the energy or not is immaterial to my model.

 

Why dies this thread remind me of the story of the four blind men and the elephant?

Bob

 

Current is the flow of charge.
Voltage is the measure of potential difference that provides the force to make charge flow.

And when those charges move the most of the energy associated with them is the magnetic fields surrounding them. There is a tiny amount of kinetic energy in a good conductor current because the electron’s mass is small and the average velocity small.

 

Here, no mention of Fields in the whole book.

I highly recommend. If you want a copy of the first edition, I can send one to you.

https://www.amazon.com/Make-Electro...cphy=9006283&hvtargid=pla-1209913628776&psc=1

 

Then you can count me as one of those.
I know and understand fields but they don't usually come to mind unless I'm talking about RF circuits or transformers.
The model of a little round (charged) ball (which generates a field) works fine for me (even if the electron doesn't exist as a particle as bogosort stated).
Whether that field is really carrying the energy or not is immaterial to my model.

If your limited model works for you then fine but don't assume the world is just your bubble because it's a far larger universe of electronics out there today. Advancements in material science and technologies are quickly changing what's needed as the basic electronic background needed to fix equipment.

 

If your limited model works for you then fine but don't assume the world is just your bubble because it's a far larger universe of electronics out there today. Advancements in material science and technologies are quickly changing what's needed as the basic electronic background needed to fix equipment.

Right, and a 15-year-old beginner needs to know all the latest! You won the pissing contest!



nsaspook

 

The poor kid!

My 2 cents:
Find something that gets the kid's interest, hopefully it kindles some sort of passion - if so - feed it. Encourage the kid to ask questions, let them nibble on the massive field in any way that interests them. Guide them to reputable resources.

Scientific curiosity can't be taught, only encouraged. Simplistic ideas are essential for anyone starting out in a field, especially children. Scientific discipline; the necessity of learning the limitations of favored ideas or explanations has to be learnt through experience. To try to protect the kid from developing ideas that they will later abandon is futile, overbearing and if successful stops the kid leaning some of the most important lessons of the scientific method.