Another example;

 

So what.
It's the electrons that create the field so they are indirectly involved in carrying the energy.
That has no effect on the understanding of simple circuits, which is what we are talking about here.

You seem to be really hung up on fields.
Reminds me of those who insist that you must look at a BJT as a voltage controlled device, where for many circuit designs it works better to think of it as a black-box current-controlled device.
Very true.
When you use an electrical component that involves fields, the you need to involve fields.
But you don't need fields to understand basic circuits.

It's like insisting you need to know about molecular and atomic electrical fields to understand how water flows in a pipe.

Yes, I'm hung up on fields as a part of the total early electronics education because I care about the field of electronics passionately and I'm training at work the next generation of electronic technicians to deal with the next generation of advance electronics. The simplistic circuit theory assumptions of no field interactions of the last 50 years leave them woefully unprepared to deal with circuits that are starting to depend on distributed components and transmission line effects because of the shrinking size of electrical circuitry and increasing signalling speeds. It's much better IMO to bootstrap the simple fields concept early when they will accept the information as a article of faith than to try and relearn bad ideas from sloppy models of circuits from 50 years ago. I can guarantee the Chinese don't have a problem teaching kids this way to advance their technical position in the world.

 

Wow, what a pointless argument

When I took my basic electronics courses fields came up pretty damn early starting with electric fields and progressing on to magnetic fields, and I was never confused.

I wasn't 15 when I started my classes, but I had a big head start because I fiddled around with stuff like train transformers and had an older brother to explain things to me.

Now don't get me wrong, I never got anything like how electromagnetism is actually a relativity effect, but if the girl want's to continue her education at some point, then she can take more advanced classes.

 

When I took my basic electronics courses fields came up pretty damn early starting with electric fields and progressing on to magnetic fields, and I was never confused.

But did that really help you in understanding simple circuits?
I'm not saying don't study fields, but it's not necessary (or particularly helpful) when a beginner is learning simple circuits.

 

Yes it did.

I believe fields are essential for learning electronics, but the physics of fields are not.

 

Have a look at this thread:

https://forum.allaboutcircuits.com/threads/educational-electronics-training-kits.78717/

 

Don't see that fields are needed at all for a basic understanding of electricity and circuits.
You apply a voltage across an impedance and the causes the electrons to move through the impedance
Don't need fields for that.

This is just a linguistic shell game. You're replacing the word "field" (because it's too mysterious?) with the equally mysterious word "voltage". You can't have a voltage without a field, so an explanation that relies solely on voltage is not an explanation. That's just hand-waving.

A beginner doesn't need to know Maxwell's field equations, but not giving them a sense of the full picture is doing a disservice to them. As nsaspook said, everyone has an intuition of field potentials from gravity. The higher we lift an object up against gravity, the more energy is stored in the field. Voltage is exactly the same. By introducing the notion of an electric field in analogy with the gravitational field, a beginner has something physical to build intuition on.

 

I would leave field theory for university level physics.
For now I would focus on current flow, series and parallel circuits.

My 2 cents worth.

 

It's the electrons that create the field so they are indirectly involved in carrying the energy.

Also incorrect.

Again, no one's saying that she needs to learn quantum electrodynamics to work on an LED blinker. Simplifications are entirely appropriate. But incorrect oversimplifications impose untenable mental models that will be hard to overcome later. It's also perfectly well to say, "I don't know how this works at the physics level, only at the electronics level." Kids love when adults admit they don't know something, and she may take the opportunity to research the questions herself.

 

The Gravity analogy.

 

I would leave field theory for university level physics.
For now I would focus on current flow, series and parallel circuits.

My 2 cents worth.

Everyone agrees with that but there should be a field theory compatible introductory (without math or physics) explanation of the circuits electrical energy for current flow, series and parallel circuits given in the very beginning IMO. We don't seem to have a problem doing this with gravity (that also has university level physics field theory) with kids but there seem to be educational resistance for basic electrical concepts. I think it's mainly because it leads to questions from curious kids that the assumptions of circuit theory can't answer using current flow directly as the electrical energy component of the circuit.

 

Also incorrect.

You made a blanket statement without explanation.
Are you saying the electrons don't create the field?

the assumptions of circuit theory can't answer using current flow as a energy component of the circuit.

What "assumptions"?

 

What "assumptions"?

http://ffden-2.phys.uaf.edu/webproj/212_spring_2015/Christopher_O'Shea/basicct.html

1.] The rate of change in magnetic flux outside of the circuit elements is equal to 0.

2.] The rate of change in current inside of the circuit elements is equal to 0.

3.] The physical length of the circuit is much, much smaller than the wavelength of the electromagnetic waves travelling through it.

The first two rules eliminate the interference of magnetic fields within and out of the circuit. The last rule lets us assume that the electrons are travelling so fast they can be said to be affecting all points of the circuit at the same time. In very large circuits, such as cross-continent power and communications networks (and even in very small circuits such as microprocessors running at very high clock speeds) this assumption is no longer true. We also assume that the wires in the circuit have no resistance; thus there is no potential difference drop through the wires and all the action happens in the circuit components (though in reality the non-uniform potential differences on the surface of the wire are what forces current through the circuit in the first place).

In addition, there are two laws, called Kirchhoff's Circuit Laws (named after the German physicist Gustav Kirchhoff) which are essentially restatements of the fundamental principle of conservation of energy:

We know that individual electrons are not traveling fast in a simple lamp circuit but the lamp lights almost instantaneously in response to the switch closure. So what is affecting all points of the circuit at the same time?

https://www.physicsforums.com/insights/circuit-analysis-assumptions/

The implications are:
No electric fields.
No magnetic fields.
No electric charges.
Kirchoff’s Laws apply instantaneously around the entire circuit, so there is no temporal first-next ordering of events.

In my opinion, this is where many basic courses fail us. Having just taught that capacitors work via electric fields, and that inductors and transformers work via magnetic fields and that all that depends on the motion of electron charge carriers, it should be emphasized that both fields and charges must be ignored for CA. Instead, the assumptions may not even be mentioned. CA also rules out pop-sci explanations such as “First apply the voltage, then the current flows, because electrons need time to accelerate.” That would violate Kirchoff’s Laws, so it is excluded in CA.

Dealing With Conduction Questions on PF A recurring problem on PF is raised by students who may have learned about components and CA and wish to go a “little bit” deeper to understand electrical conduction. To make it worse, many are unwilling to go further with serious study and unwilling to deal with math beyond what they already know. Sometimes, the tip-off is when the student mentions electrons. On the other hand, we have PF veterans who wish to help these students while avoiding pop-sci or lame analogies. How should we respond?

CA is a perfectly valid way to solve complex problems but the assumptions and limitations of circuit theory also need to be understood early in the learning process IMO.

 

This idea that charges travel faster than their carriers IMHO is nonsense, the reason the effect of current is near instantaneous is because the carriers all move at the same time and the affect of the current is due to the electrons already at the load not the ones that just entered the wire.

But, I will concede when someone can explain how charge can travel faster than its carrier.

 

The water analogy breaks down. I think she needs to know this. it's a way of explaining electricity simplisticly.

I learned circular orbits for electrons and had that thrown away once you learn probability theory.

A water, bucket and a few different diameter pipes. can easily teach energy storage, resistance, voltage.
Even a padle wheel. The higher the water, the more potential energy or the faster it spins.

Safety needs to be covered somewhere an the difference of AC and DC current.

Don't forget the conservation of mass an energy.
The LED drops some voltage, it uses some current,
It uses electrical power to produce light and heat. Both are forms of energy.

Don't teach her the tongue trick to test 9V batteries.

Donlt teach her that a 12V battery is not dangerous. A wrench across a car battery is dangerous.

What are fuses?

I'm not sure if explaining a rocket ignitor is the right thing to do.

The concept of why this wire heats u and this one doesn't.

the concept of math makes some sense.


Above all determine what her learning style is and use it.

1. Visual
2. verbal
3 Kinestetic (learning by repetition or how you might learn to ride a bike)

or a combination.

If she is dificient in these methods, work on developing them.

Make a circuit and then draw the schematic. Sometime later have her make the circuit using the schematic.

 

"Real solutions don't come by thinking about little round balls"

https://www.researchgate.net/profil...ovices-and-experts-model-electric-current.pdf

Children coming into high school have a vague and often fearful image of electricity.
Once they encounter formal circuitry they are required to understand a mechanistic
model of electron movement through a wire which, by analogy and metaphor, is
closely allied to fluid transfer. All the language of electricity reinforces this model.
Teachers of electricity have a strong belief that the particulate model is both useful
and 'correct'. They themselves hold this image, and few have a strong field concept.
Clearly, however, their students have difficulty with the model and hold
misconceptions and alternative conceptions about circuit behaviour which lead to
difficulties with problem solving. The electron-transfer model is ubiquitous: it
appears in all texts whether they be designed for physics or engineering students or
for electricians.
Experts, however, do not retain this imagery. They regard electricity as a
field-like phenomenon, formed of endless loops, and their understanding is
inextricably tied to the concept of electricity as useful energy. Their vocabulary deals
with the task, the load, the job and the field - and they find the micro-view of electron
transfer irrelevant and, at times, confusing.
Changing the perceptions of what constitutes useful knowledge in electricity is
a difficult and challenging task. It is important, however, to address the problems
experienced by students in this subject, because a working understanding of
electricity is required, even at an elementary level, in most countries. Research
indicates that students do not have this understanding, that they have problems with
conventional circuitry and that their mental images are confused. Those who work
with electricity, however, have evolved a field-like image and do not need the old
model of current as 'electron flow'. Perhaps we as teachers should examine its
usefulness for the next generation of students, whether they are proceeding to a
career in electricity or not.

 

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.

 

"All the language of electricity reinforces this model.
Teachers of electricity have a strong belief that the particulate model is both useful
and 'correct'. They themselves hold this image, and few have a strong field concept.
Clearly, however, their students have difficulty with the model and hold
misconceptions and alternative conceptions about circuit behaviour which lead to
difficulties with problem solving. "

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?

 

you guys are really missing the point. If I want someone to enjoy my hobby of drinking scotch with me, I don't start by telling them to read about microbiology and fermentation process, distillation strategies, and storage methods for aging. I simply ask them to taste with me. In other words, hands-on, make a circuit that does something. Only then can you step back and answer the questions someone would have (why can I power an Incandescent without polarity concerns, but a motor reverses and an LED doesn't do anything when I reverse polarization). Do experiments that create questions. And, who cares about fields. So much electronics can be taught without that crap.

 

Are you saying the electrons don't create the field?

Correct, the electrons are the field. More specifically, they're one of the interacting quantum fields whose effects we associate with the electromagnetic field of classical physics. Again, I wouldn't focus on such detail with a 15 year old (unless they were genuinely interested), but you asked.