# What is electricity made out of?

ZapperZ
Staff Emeritus
I'm actually going to go in the opposite direction from bhobba. I'm going for the simplest, naive definition.

If by "electricity" we mean "electric current" (as I've gathered from the OP), then it is defined as moving electric charges.

Done!

Zz.

doglover9754, bhobba and russ_watters
russ_watters
Mentor
I'm actually going to go in the opposite direction from bhobba. I'm going for the simplest, naive definition.

If by "electricity" we mean "electric current" (as I've gathered from the OP), then it is defined as moving electric charges.

Done!
I was thinking the same thing. Similarly, there need not be any argument over static electricity; it has a different name, so it can be different; It's a buildup of charge that isn't otherwise moving.

There is nothing wrong with, for a first pass, keeping things very simple.

doglover9754 and bhobba
ZapperZ
Staff Emeritus
I was thinking the same thing. Similarly, there need not be any argument over static electricity; it has a different name, so it can be different; It's a buildup of charge that isn't otherwise moving.

There is nothing wrong with, for a first pass, keeping things very simple.
Exactly. That is why I qualified the definition of "electricity" as being "electric current" based on what the OP posted in the very first post. Otherwise, we are making this more complicated than it should and we seem to end up chasing our own tails.

Zz.

doglover9754, bhobba and russ_watters
RonL
Gold Member
Exactly. That is why I qualified the definition of "electricity" as being "electric current" based on what the OP posted in the very first post. Otherwise, we are making this more complicated than it should and we seem to end up chasing our own tails.

Zz.
Or the tail of an electron

doglover9754
Gold Member
While in university long time ago there was lectures dealing with electric properties of metal on micro scale. Surface of metal was teaming with microcurrents cancelling each other etc. Call it electric equivalent of Brown motion if you wish. But yes, I consider these kind of arguments academic and of no use.
My teacher in 6th grade did mention something like that. But he only mentioned that nothing more.

sophiecentaur
Gold Member
Good idea. Despite the high level of knowledge that you will find on PF, there is nothing to beat a well written passage in a good text book, which has been thought about and edited with skill over a substantial amount of time. These posts are largely 'accurate' but they were written on the spur of the moment and it would be possible to get some wrong ideas if you were to rely only on them alone.
PS 10 minutes should be only a start. Think more in terms of hours and days. It is a hard subject.

doglover9754
Borek
Mentor
The problem I have with this approach (limiting electricity to current and moving charges) is that most (if not every) physics course I have seen starts the "electric" (or rather "electromagnetic") part with the static electricity, Coulomb's law, Gauss law and so on. Thus I prefer a bit more universal definition at start to avoid explaining students later that they were wrong thinking electricity is just about currents.

And knowing students - if they can misunderstand something, they will. Why introduce misconceptions and battle them later instead of getting things right from the very beginning?

doglover9754
OmCheeto
Gold Member
My teacher in 6th grade did mention something like that. But he only mentioned that nothing more.
IMHO, "Electricity" seems to be a word similar to "Physics" or "Chemistry".

Going back to your original question:

So my question is what is electricity made out of. Atom wise.
Would it make sense to you to ask; "What is physics made out of?"

nsaspook, doglover9754 and sophiecentaur
ZapperZ
Staff Emeritus
The problem I have with this approach (limiting electricity to current and moving charges) is that most (if not every) physics course I have seen starts the "electric" (or rather "electromagnetic") part with the static electricity, Coulomb's law, Gauss law and so on. Thus I prefer a bit more universal definition at start to avoid explaining students later that they were wrong thinking electricity is just about currents.

And knowing students - if they can misunderstand something, they will. Why introduce misconceptions and battle them later instead of getting things right from the very beginning?
But the words need to be used within the context, and that can tell you what the original intention or scope of the question involves. The OP specifically mentioned "lightning", which led me to believe that the OP is thinking of moving charges (even though a lightning is not strictly the same as electric current).

I highly doubt that the OP wants the full treatise on electric current, electric field, electric potential, electric charge, etc... etc. If he does, then he needs to go back to sleep and stop asking these silly questions in this forum at ghastly hour of the day.

Zz.

doglover9754 and bhobba
bhobba
Mentor
Would it make sense to you to ask; "What is physics made out of?"

Its not quite that pessimistic.

As I said I could answer what it is, but you need to build up to it and think as you go along.

But since you bought it up I will just give a little glimpse of he answer. We have a very powerful theorem called Noethers Theorem that leads us to believe, very strongly in things like conservation of momentum, energy etc. Have a look at the Coulomb Force Law. Notice something? According to it you move a charge and instantaneously the other charge experiences a change in force. But relativity tells us it cant happen instantaneously. There is a lag - this of course means it is strictly wrong. One way it's wrong is it would mean momentum and energy is not conserved. But Noether says it must be. Whats going on? Well there was this guy called Wigner that looked into it and he came up with a no go theorem. His specialty was using group theory to analyse physics. Anyway this no go theorem says if you want these conservation laws something else must be involved to carry away this momentum and energy. This something is called a field and since it has momentum and energy we generally think of it as real. But to complicate matters Wheeler and Feynman came up with EM without fields - but it was pretty weird - stuff traveling backwards in time even. You can look up the theory but its more a curiosity nowadays. I actually said more than I wanted. I wanted to gradually build up to whats going on.

Thanks
Bill

doglover9754 and OmCheeto
Borek
Mentor
But the words need to be used within the context, and that can tell you what the original intention or scope of the question involves. The OP specifically mentioned "lightning", which led me to believe that the OP is thinking of moving charges (even though a lightning is not strictly the same as electric current).
Yes, context matters, but I still don't think broadening OP's understanding can hurt (especially as static electricity is not an exotic concept). And I definitely don't mean going into minute details.

doglover9754
bhobba
Mentor
I highly doubt that the OP wants the full treatise on electric current, electric field, electric potential, electric charge, etc... etc. If he does, then he needs to go back to sleep and stop asking these silly questions in this forum at ghastly hour of the day.
The question, specifically, was what is electricity made of. I wanted to build up to it in stages, but I ended up giving the full answer - its something we believe in because of conservation arguments. Further detail would take us into QED, gauge symmetry, Wigner's proof that fields must be tensors, way beyond this threads level.

With specific questions I must admit I find it hard sometimes to determine context - was it the actual answer what physics tells us, or simply what is electric current. I think both have been answered so now it is up to the OP what direction they want to go or just leave it at what has been posted.

Thanks
Bill

Last edited:
doglover9754

Its not quite that pessimistic.

As I said I could answer what it is, but you need to build up to it and think as you go along.

But since you bought it up I will just give a little glimpse of he answer. We have a very powerful theorem called Noethers Theorem that leads us to believe, very strongly in things like conservation of momentum, energy etc. Have a look at the Coulomb Force Law. Notice something? According to it you move a charge and instantaneously the other charge experiences a change in force. But relativity tells us it cant happen instantaneously. There is a lag - this of course means it is strictly wrong. One way it's wrong is it would mean momentum and energy is not conserved. But Noether says it must be. Whats going on? Well there was this guy called Wigner that looked into it and he came up with a no go theorem. His specialty was using group theory to analyse physics. Anyway this no go theorem says if you want these conservation laws something else must be involved to carry away this momentum and energy. This something is called a field and since it has momentum and energy we generally think of it as real. But to complicate matters Wheeler and Feynman came up with EM without fields - but it was pretty weird - stuff traveling backwards in time even. You can look up the theory but its more a curiosity nowadays. I actually said more than I wanted. I wanted to gradually build up to whats going on.

Thanks
Bill
Doglover is a 13 year old girl... She wants some reasonable answer which can be expanded upon later if need arisen.

If someone ask you what is "water", you dont need to go to issues like what hadrons are made of?, what is a strong nuclear force holding hadrons and nuclei of atoms together?, theory dealing with molecular orbitals, wave function, Schrodinger equation etc. Neither would you need to explain that "antiwater" is mooving backward in time to satisfy CPT symmetry and if mixed with water it would explode badly forming gamma rays and mesons which would decay later etc.

Merlin3189, GuiliuG, doglover9754 and 1 other person
symbolipoint
Homework Helper
Gold Member
What is electricity made out of?
It is made of electrons, or other particals of electric charge. "Electricity" is the movement, or the flow of these charged units.

doglover9754
Gold Member
Would it make sense to you to ask; "What is physics made out of?"
Hmmm... yes and no.

OmCheeto
Gold Member
Doglover is a 13 year old girl...
Her profile also says; "Completed undergrad in Working towards being a Mechatronics Engineer"

"undergrad" implies to me that she's one smart cookie, to have made it that far, at 13.

"girl" is irrelevant, IMHO, as I read half of Nancy Roman's interview from 1980 last night. It kind of confirmed my suspicions that people sometimes use their gender to pretend to be feigning ignorance.

doglover9754
Gold Member
Doglover is a 13 year old girl... She wants some reasonable answer which can be expanded upon later if need arisen.

If someone ask you what is "water", you dont need to go to issues like what hadrons are made of?, what is a strong nuclear force holding hadrons and nuclei of atoms together?, theory dealing with molecular orbitals, wave function, Schrodinger equation etc. Neither would you need to explain that "antiwater" is mooving backward in time to satisfy CPT symmetry and if mixed with water it would explode badly forming gamma rays and mesons which would decay later etc.
Wow... now that’s something I don’t hear often. Thanks!

Gold Member
Her profile also says; "Completed undergrad in Working towards being a Mechatronics Engineer"

"undergrad" implies to me that she's one smart cookie, to have made it that far, at 13.
I’d like to be as smart as you say but I’m only an 8th grader right now. I may be ahead in most of my classes, taking summer school and all, but I like to take my steps one at a time. That’s why I’m not taking algebra even if I have the knowledge of a student who is taking that course right now.

Gold Member
By the way, thanks for telling me that my gender doesn’t matter. It’s nice to see that there is someone who doesn’t see a difference between genders. Knowledge wise. @OmCheeto

davenn