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I am new to the physics category of the Stack Exchange site. I apologize if my question is wrong, too broad, simple, or worded incorrectly. I am just trying to figure out what is true and false when it comes to electricity and its vast world. I want to have the right resources to learn from, however, I have come across many things that say electricity is the flow of electrons; and then there are people that contradict this statement.

For example, this guy said,

"First we must realize that "electricity" does not exist. There is no single thing named "electricity." We must accept the fact that, while several different things do exist inside wires, people wrongly call all of them by a single name."

I looked at some more of his information on his website, here are a few links:

http://amasci.com/miscon/whatis.html

http://amasci.com/amateur/elecdir.html

http://amasci.com/miscon/eleca.html

I am not asking anyone by any means to read everything, if someone could just browse it briefly - a few sentences or something, to let me know if these articles align with the truth and facts of electricity - then I would really like to study the articles and learn

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    $\begingroup$ Hi spiderman0297, and welcome to Physics Stack Exchange! I've removed a number of comments that were attempting to answer the question and/or responses to them. Commenters, please keep in mind that comments should be used for suggesting improvements and requesting clarification on the question, not for answering. $\endgroup$ – David Z Jun 22 at 2:53
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The idea that electricity "does not exist" is just verbal sophistry along the same lines as "matter does not exist, it is frozen energy" or, "you do not exist, you are a figment of your own imagination". At best these are all just over-dramatic and misleading ways of saying that what these things actually are is not what you probably think they are. At worst, misguided eccentrics create "straw" definitions of such well-known words just so they can burn them and trump them with their own untenable notions.

This last, sadly, is what is happening with the pages you link to. Although basically sound at an experimental and phenomenological level (and that has to be clearly acknowledged), he argues for his own wacky definitions of words.

The guy claims that the scientific definition "means only one thing: quantities of electricity are measured in Coulombs". In fact it is electric charge which is measured in coulombs, not "electricity" per se; his claim is a classic example of giving a straw definition so that he can debunk it.

He concludes that "Because there are *two* things flowing, we cannot call them both by the name 'electricity.'" This is typical eccentric pedantry; of course we can. We can simply say that the phenomenon of electricity comprises electric charges and electric fields. And we do.

For example "static electricity" is a buildup of charge, which creates an electric field capable of making your hair stand up or making molecules of glue stick together. Electricity as found in domestic wiring has three main properties; its flow is measured in (electron) charges per second or Amps, its "pressure" in Volts and the power (flow of energy) carried by the charged electrons in Joules per second or Watts. All these are aspects of electricity. There are many others.

All the sophistry in the world will not change these facts, only what we choose to call such things.

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    $\begingroup$ I've deleted a number of inappropriate or obsolete comments and/or responses to them. $\endgroup$ – David Z Jul 24 at 0:51
  • $\begingroup$ > his own wacky definitions" . On the contrary, those listed definitions are from reference and text books, and are in wide common use (check your personal collection of K-12 textbooks, pop science books and articles, etc. Or try goog search to find many instances.) $\endgroup$ – wbeaty Jul 24 at 1:43
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Electricity is not a well-defined term in physics. It's a layman's term that means something like what physicists call electrical phenomena. However it also gets used (like your first link says) for numerous specific phenomena that physicists have more specific terms for:

  • Electric current

  • Electrostatic potential

  • Electric field

  • Electric power

  • etc.

So if you're talking to your cousin you can tell them "the electricity's out" or whatever. But when you're discussing physics you'll express yourself more clearly if you use the specific terms for the specific aspect of electricity that you want to discuss.

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    $\begingroup$ I agree with this answer as I share the same opinion - I'd describe electricity as a collective term. I think this answer is the most correct. $\endgroup$ – Jacob Schneider Jun 23 at 10:07
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    $\begingroup$ or "sound" doesn't exist: it's just air vibrations, solid vibrations, even oscillating electric signals, biological nerve impulses, ... $\endgroup$ – user253751 Jun 23 at 20:17
  • $\begingroup$ Yes, "electricity" is a class of phenomena, similar to "optics" or "weather." Yet many texts are teaching that "electricity is a form of energy." And the SI MKS units specifically state that the "quantity of electricity" is to be measured in coulombs. So immediately we have a problem. Does physics say that "electricity" is the joules? Or is it the coulombs? (On the other hand, if textbooks started saying that "optics is a form of energy," aren't they misleading their students? Optics is a subject-heading, a phenomena-class. By that example, electricity CANNOT be a form of energy.) $\endgroup$ – wbeaty Jul 23 at 9:47
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Electric current is the flow of charges.

In most metals, electrons are the majority charge carrier, but that's not the case for all materials. For example, in pure water, there aren't free electrons, and the charge carriers are H$^+$ and OH$^-$ ions. There are not many ions in pure water, so it's a poor conductor. But dissolve some table salt and you introduce Na$^+$ and Cl$^-$ ions and improve the conductivity a great deal. A chemist could tell you which is the majority carrier, as well as a bunch of other stuff that's happening.

In some materials, especially p-type semiconductors, the most parsimonious description of the majority charge carrier is that they are positively-charged "holes" in the electron ocean filling the crystal. Whether those quasiparticles are "real" in the sense that electrons are real is one of those questions that gets more slippery the more you think about it.

You link to Bill Beaty's amasci.com. The more I learn about electromagnetism, the more Beaty's style and content impress me. I say you keep reading.

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    $\begingroup$ The question of whether or not electrons move when current flows in a p-type semiconductor is independent of whether or not you regard the "holes" as real "particles." $\endgroup$ – Solomon Slow Jun 22 at 15:56
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    $\begingroup$ @SolomonSlow The electrons also move in an electrolyte where the majority charge carriers are anions rather than cations. Thinking of hole conduction in terms of electron motion is like thinking of a rising air bubble in terms of falling water. It's technically correct, but it makes some important features of the dynamics harder to predict than they should be. $\endgroup$ – rob Jun 23 at 1:47
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    $\begingroup$ @rob, In physics, and in many other fields of study, we can understand a phenomenon at different levels of abstraction—sometimes many levels. The key to understanding any particular thing often is figuring out the best level at which to explain it. But, that doesn't make other levels any less real. In the most satisfying explanation of PN semiconductor junctions, there are no electrons in the P-type material—only holes. But, if we want to understand what the "holes" actually are, we must shift to a lower level explanation, in which, we talk about how electrons move through the crystal lattice. $\endgroup$ – Solomon Slow Jun 23 at 12:12
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    $\begingroup$ @SolomonSlow I agree that there are many levels of abstraction with different advantages. At an even lower level, "an electron" is not a thing you can grab but an excitation of a field which obeys certain symmetries. In p-type semiconductors, the low-energy, localizable excitations of that same field have positive charge. You might enjoy A Different Universe by Laughlin, who won a Nobel for taking quasiparticles seriously; the consequences of applying this condensed-matter approach outside of condensed matter are too much to fit into a comment, and too far afield to edit into this answer. $\endgroup$ – rob Jun 23 at 14:38
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"Electricity" was coined by William Gilbert in his book De Magnete (1600s) . The etymology of word is as as follows.

The New Latin adjective electricus, originally meaning 'of amber', was first used to refer to amber's attractive properties by William Gilbert in his 1600 text De Magnete. The term came from the classical Latin electrum, amber, from the Greek ἤλεκτρον (elektron), amber. The origin of the Greek word is unknown, but there is speculation that it might have come from a Phoenician word elēkrŏn, meaning 'shining light'.

The word electric was first used by Francis Bacon to describe materials like amber that attracted other object .

An "Electrick" or "Electrick body" was a non-conductor, or an object capable of attracting "light bodies" (like bits of paper) when excited by friction; a piece of amber is "an Electrick", while a piece of iron is not. "Electricity", then, was simply the property of behaving like an electric, in the same way that "elasticity" is the property of behaving like an elastic

Source : https://en.m.wikipedia.org/wiki/Etymology_of_electricity

Electricity in physics is broadly divided as Current Electricity and Static Electricity.

I would say Electricity is the term that defines whether the electrons in a system move from one point to another(current electricity) or just accumulate at a particular point(static electricity)

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    $\begingroup$ Etymology is not meaning. The meaning of the word to Francis Bacon is barely relevant to the use and meaning of the word today. $\endgroup$ – aschepler Jun 23 at 6:07
  • $\begingroup$ @aschepler , ya . Thats why you should read the last paragraph $\endgroup$ – Noah J. Standerson Jun 24 at 3:14
  • $\begingroup$ A "flow of electricity" ...is it measured in amperes, or in watts? (Is electricity a form of energy? If so, then flowing electricity is joules per second, NOT coulombs per second.) Heh. Maybe the hundreds of texts describing "flow of electricity" as motion of coulombs ...are wrong? Faraday is wrong? So is Maxwell, so is Einstein, Thompson, etc., etc. So are the SI standards, MKS which specifically defines "quantity of electricity" to be measured in coulombs. $\endgroup$ – wbeaty Jul 23 at 9:52
  • $\begingroup$ @NoahJ.Standerson If you find this fascinating, perhaps see Faraday's 1839 article "Identities of Electricities..." where he shows that static or "common" electricity is the same thing as battery-electricity, is the same thing as bioelectricity. Faraday concludes that just one "electricity" exists, but there may be wide variation in the values of amperes and coulombs being exhibited. So "static" electricity is really just high voltage at low or zero current, while "current electricity" is the opposite, having high current with low voltage and charge. amasci.com/miscon/maxwell.html#farad $\endgroup$ – wbeaty Jul 24 at 2:08
  • $\begingroup$ @wbeaty , Thank you for the links. I will go through it asap $\endgroup$ – Noah J. Standerson Jul 24 at 8:19
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Unfortunately, I was not access those links (?), but I would say that the electricity is a broad term that encompass the concepts related to how electrons interact with matter, especially as related to how that can be utilized for radiation and power. "Electricity" is not a word that you be used rigorously in scientific lectures or texts - again, it is a broad term, and the scientifically-meaningful quantities that are included in that have specific terms such as "voltage" or "resistance."

I think few physicists would say "electricity is the flow of electrons." I would call current the flow of electrons, it is defined as the change in charge per unit time (for example, in a wire): $$ I = \frac{dq}{dt}. $$ Currents are driven by electric fields that create gradients in energy/potential/voltage -- electrons feel the force of the field and their energy changes as they move through the field. Electric fields are generated both my charges like electrons as well as time-changing magnetic fields (such as from a solenoid or coil). Thus, the study of "electricity" is highly related to the study of magnetism.

I highly recommend these introductory texts:

  1. Knight, R. Physics for Scientists & Engineers: A Strategic Approach with Modern Physics, 2003.
  2. Chabay, R. & Sherwood, B. Matter & Interactions, Volume II: Electric and Magnetic Interactions, 2015. that will provide a conceptual and introductory overview of electricity and magnetism using algebra and some calculus.

For the advanced reader, the ubiquitous text is Introduction to Electrodynamics by David Griffith, which provides a deeply sophisticated and mathematical approach to the theory of electromagnetism, including electrostatics, dynamics and radiation.

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    $\begingroup$ Currents in wires are flows of electrons. In plasmas or electrolytes they could be the flow of positively charged ions. In semiconductors they can be the flow of electron-holes. $\endgroup$ – The Photon Jun 22 at 4:04
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Electricity is what consumers call the product delivered by energy providers and which makes their home appliances run. Not to be confused with gas or oil.

Physicists talk about electrodynamic, electromagnetism and electronics.

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Electrical engineer here.

Thank you for a question that is so dear to me, and is so important to our understanding of the universe.

Once you get past the semantics, which are covered in other questions, it seems the core of your question is what is happening when current flows and is it more than the simple analogy of flowing water?

The bulk of this understanding is covered in the laws that Faraday deduced and Maxwell created the formulas for. Maxwell's equations are difficult even for me, I don't usually use first principles like that either; but if you want to spend some time learning calculus and tensors, you too can get down to those basic principles.

I recommend looking at an actual example, such as electron flow through copper wire. A copper wire is made of a lattice (a kind of crystal) of copper ions. Because it is missing some atoms to complete its shell there are free electrons that move through this lattice similar to a gas. You will note if you examine the tables on conductors that some metals that are good electrical conductors also conduct heat well for the same reason - heat is also a vibration of electrons and depends on free electrons to easily transmit heat. There are exceptions of course, such as thermally conductive paste. [https://www.thoughtco.com/examples-of-conductors-and-insulators-608318]

Normally, the free electrons move about randomly in the metal; but when you subject it to electrical potential, the electrons move in a more organized fashion from negative to positive potential. Electrons have a negative charge. They are attracted to the positive end of the battery. The free electrons move through the copper, flowing from the negative to positive terminal of the battery

Note that they flow in the opposite direction to conventional current; this is because they have a negative charge. Most electrical courses use current flowing from positive to negative which is called hole flow, its just a counter example because traditionally it was thought current flowed from positive to negative. I mention this because a lot of web pages and text books will say current flows from positive to negative; its true; if you, instead of looking at the movement of the electrons, you look at the movement of the holes that the electrons leave.

Using the word electrical current is to simply say an electrical charge is moving through the wires due to the action of the potential, say a battery on the wire. Current is the rate at which charge flows past a point on a circuit. The current in a circuit can be determined if the quantity of charge Q passing through a cross section of a wire in a time t can be measured. The current is simply the ratio of the quantity of charge and time. Current = I = Q/t where I is current in amps, Q is charge, and t is time. Q, charge is measured in coulomb. 1 ampere = 1 coulomb / 1 second. That is a bunch of electrons, lets say 1 columb pass a spot on the copper wire in 1 second, then you have one ampere of current.

The path of a typical electron through a wire could be described as a rather chaotic, zigzag path characterized by collisions with fixed atoms. Each collision results in a change in direction of the electron. Because of collisions with atoms in the solid network of the metal conductor, there are two steps backwards for every three steps forward. The overall effect of the countless collisions is that the overall drift speed of an electron in a circuit is abnormally low. A typical drift speed might be 1 meter per hour, with a potential applied!

When you apply an electric potential across the two ends of the circuit, the electron continues to migrate forward. Progress is always made towards the positive terminal. there are many, many charge carriers moving at once throughout the whole length of the circuit. Current is the rate at which charge crosses a point on a circuit. A high current is the result of several coulombs of charge crossing over a cross section of a wire on a circuit. If the charge is densely packed into the wire, then there does not have to be a high speed to have a high current. Instead, there just has to be a lot of them passing through the cross section.

You might think that for this reason electrical current is slow, but as you know its fast, very fast. In fact it travels at nearly the speed of light, and this is proven by Maxwell's equations, yes the nature of what you are asking is described by his four equations.

When you flip a switch it causes an immediate response throughout every part of the circuit, setting charge carriers everywhere in motion in the same net direction. While the actual motion of charge carriers occurs with a slow speed, the signal that informs them to start moving. The electrons that light a bulb do not have to first travel from the switch through the entire length of wire to the filament. Rather, the electrons that light the bulb immediately after the switch is turned to on are the electrons that are present in the filament itself. As electrons leave the filament, new electrons enter it. The electrons are moving together much like the water in the pipes when the pipe is already full of water. The water that comes out of the tap first is the water that was near the nozzle.

Now you ask is it more than that? Well yes, it is. Electromagnetism cannot be separated, electricity is magnetism and magnetism is electricity. Everything that exists, everything you interact with, everything you see, all the radio waves, xrays, the energy from the distant stars, it is all electromagnetic waves and it is governed by the Faraday and Maxwell observations and equations, respectively. What you ask gets to the very fundamental question of mater, energy and existence. I would argue that your simple question is not simple at all, it gets to the core of the fundamental forces of nature.

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  • $\begingroup$ You have duplicated the entire text of your answer as far as I can see. Perhaps you could check it and delete what is not required. $\endgroup$ – rghome Jun 23 at 8:21
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    $\begingroup$ There are also some errors in here. To take just one example, "Remember I said that good electrical conductors are good heat conductors. This is why wires get hot when they carry a lot of current." is not true; better conductors such as copper or silver heat up less than poorer conductors such as iron or carbon. $\endgroup$ – Guy Inchbald Jun 23 at 9:31
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    $\begingroup$ RE: Guy Inchbald, I can see the misunderstanding. Let me try to clear it up, here and above. What I said is true - generally; but not always a material that carries electricity well, also carries heat well, that is because they all depend on free electrons. What you are talking about is resistivity. It is resistivity that makes the wires hot. I see how I made it confusing and I will try to edit it to make it more understandable. $\endgroup$ – cuevobat Jun 24 at 0:10
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The article you cite is apparently written to express a disagreement with the wide use of the term "electricity", which is admittedly very broad and vague. "Electricity does not exist" does not mean the author is denying the existence of the underlying physical phenomena, it simply means that in almost all cases a more precise term should be used, so that very few things (if anything at all) could be legitimately called "electricity".

For instance, most electric appliances actively use the magnetic field as well, so they should be technically called "electromagnetic".

If your goal is to understand the physics of electricity (or electromagnetism), you clearly picked the wrong reading material. You should find a book explaining the basic concepts, not an article arguing over terminology.

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  • $\begingroup$ Optics does not exist! What? Suppose all textbooks taught us that "optics comes out of flashlights; the sun emits rays made of optics." Then Bill Beaty would loudly object, saying that "Optics" is neither a form of energy nor a "stuff" which flows along ...and that this "optics" does not even exist! (On the other hand, light and photons certainly exist, as do EM waves.) So, do dynamos spew out electricity? And in AC cables, does electricity wiggle back and forth? Nope. There is no such electricity. Instead, "Electricity," like Optics, is only a field of science, and a class of phenomena. $\endgroup$ – wbeaty Jul 24 at 2:00

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