Talk:Electric field
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Error in Definition of Efield and Problem in Qualitative Description
Definition Problem: The current definition on the page is: "The electric field E is defined as the force F experienced by a stationary positive unit point charge q at position r (relative to Q) in the field". Problem: The Electric field is not a force. It is not even a set of forces. It is a set of forces per unit charge that can be defined by a vectorvalued function. The most important change that needs to be made is the part about force per unit charge. By analogy, one can reference gravitational field. One would never say that "The gravitational field G is defined as the force F experienced by a stationary point mass m at position r (relative to M) in the field". The reason is that the gravitational field is not a force. Mathematically, it is a tool for computing any force affected by the field. Here is my suggestion for changing the definition (I use rectilinear coordinates because they are familiar to more readers):
 Proposed Change:
Consider a point charge q with position (x,y,z). Now suppose the charge is subject to a force due to other charges. Since this force varies with the position of the charge and by Coloumb's Law it is defined at all points in space, is a continuous function of the charge's position (x,y,z). This suggests that there is some property of the space that causes the force which is exerted on the charge q. This property is called the electric field and it is defined by
Notice that the magnitude of the electric field has units of Force/Charge. Mathematically, the E field can be thought of as a function that associates a vector with every point in space. Each such vector's magnitude is proportional to how much force a charge at that point would "feel" if it were present and this force would have the same direction as the electric field vector at that point. It is also important to note that the electric field defined above is caused by a configuration of other electric charges. This means that the charge q in the equation above is not the charge that is creating the electric field, but rather, being acted upon by it. This definition does not give a means of computing the electric field caused by a group of charges.
 End Proposed Change
Being somewhat unfamiliar with HTML or whatever, I could not get the subscripts to have a space; It should say "On q", not "On'q". Someone who knows what they are doing should maybe help out with that if they get a second.
Qualitative Description Problem: The qualitative definition makes the same mistake of defining the E field as a force that would hypothetically exist under some condition, rather than force per unit charge, but I am willing to give some artistic license to the qualitative description. My problem is with the last analogy: "...The electric field is to charge as gravitational acceleration is to mass and force density is to volume." I like the gravity analogy, but I have no idea what this is referencing: "force density is to volume". That might be true in some context, but I have a degree in physics and nothing springs immediately to mind. I recommend clarifying the context or just scrapping it because it is confusing. It might even be misleading because definitions of E field often reference space which is not meant in the everyday sense of the word; In mathematics, space is a set of points which is very different than a scalar associated with some set of points (which is what volume is).
I will wait a little and see what people think of this and if I do not get any complaints I am going to change the definition in the article. I have not read the citations in the article, but I have read a couple of other resources (college text books) that I can cite in the article that back up my definition. I suspect that the other sources give accurate definitions, but that they were misinterpreted when paraphrased.
Rewrote definition section
The previous version of the Definition section seemed to be focused on defining electric charges rather than the electric field. I edited that information out and also merged the Coulomb's Law section, since it was essentially defined in terms of Coulomb's Law (and Gauss's Law). I included several common equations that could be used as mathematical definitions of electric field. It might still need a little more cleaning up right at the end, however, but it should be accurate, at least. 71.225.188.211 (talk) 23:39, 10 February 2010 (UTC) To me it is most obvoius that uncontrolled democracy is undistinguishible from pure chaos. Just listen to this mambojambo "In physics, an electric field is a property that describes the space ". Describes what? The space? And further down where the charge q approcahes zero. I am professional engineer and through my entire career I have know that the the probe charge is REMOVED to infinity. And the same with the rest of the .....Lord almighty, where are we going! —Preceding unsigned comment added by Sergei.Borodinski (talk • contribs) 19:15, 12 February 2010 (UTC)
Further rewriting desirable
This is unnecessarily verbose  'The strength or magnitude of the field at a given point is defined as the force that would be exerted on a positive test charge of 1 coulomb placed at that point; the direction of the field is given by the direction of that force.' Since E has been defined as a vector, and force is also a vector, it suffices to say 'E is defined as the force, of electric origin, on a unit positive charge'. Simplicity makes for clarity, I feel. —Preceding unsigned comment added by 82.32.49.157 (talk) 08:37, 25 November 2010 (UTC)
Terminology cleanup
I'm pretty new here, but I'm trying to help make the electromagnetics articles less messy and more readable. I notice there is a separate article (a stub) for electric field intensity. It should be removed, and instead pointed here, right? I'm adding mention of that term to this page, in addition to some other readability changes. Please let me know if I do anything bad! Xezlec
 Okay, I went ahead and did the abovementioned redirect. This is ok, right? Xezlec 04:11, 31 December 2005 (UTC)
 Sorry for continued nitpickery. I've now expanded the article to mention that a changing Bfield also produces an Efield. I revised some things to make it clear that most of the rest of the article applies only to the static case. I'm not sure the overall structure of the article is still "prettylooking" but at least it's more complete and more strictly correct now. Xezlec 06:45, 31 December 2005 (UTC)
I disagree with the use of the term "electric field intensity" in referring to the electric field vector. Traditionally the term intensity refers to the modulus squared of the electric field (or the square of the electric field strength to use the terminology in the article). Intensity is a scalar quantity, not a vector. Regards, Justin Hannigan.
r^3
I don't like the formulation with the r vector on top and the r^3 on the bottom. Can we have r^2 on the bottom and an r unit vector on top? I think for young people (high school students) this could be confusing to them. It might lead them to think that the electrostatic force is proportional to 1/r^3, which it is not. For the article to be written for all audiences, I believe it should use the form that I prefer, using a unit vector instead. Comments? Dave
 Done. Dave is right, it is confusing with r^3. Of course, some readers may not understand what the hat means, and finding out isn't very easy, but that's alright. Maybe someone can make a note of it in the text (though that might require inline TeX :P ). The reason I didn't do it this way to start with is that the formulas were written before TeX came along: there wasn't really any way to make a hat. Do you think the vectors should be on the top of the fraction, or outside the fraction like I just did it?  Tim Starling 05:38 Apr 1, 2003 (UTC)
 Thanks. I'm glad someone else prefers it this way. It is nice to look at a formula and right away see the dependency that you care about, without having to think about the vector. BTW, I like the vector "outside" the \frac like you did it. Very clean, separates the magnitude part from the vector part. Totally unambiguous. dave
 p.s. Do you know if we are supposed to be using TeX for everything? I read the page about Wiki mathematics or whatever, but it sort of left the issue up in the air. It said that TeX is bad for inline due to the weird line heights it creates, and it is slow for web pages to load and text browsers can't see it. But it's so easy to write in TeX style. Is there any consensus?
I'm basically boycotting TeX  I didn't participate in "texification" except in a few special cases. See wikitechl Jan 2003 under "ugly <math>" for why  I argued that it's ugly, due to being too large compared to the text, but everyone just ignored me and argued against me on all sorts of silly little points while ignoring the obvious issues. Also, you can't wikify TeX like you can HTML  if it was up to me I would have left the magnetic field formulas like this. Getting back the point, no I don't think there is any consensus, although I wasn't really following the mailing lists back then. Now that the range of TeX displayed as HTML is bigger than it was originally, you can probably use TeX in most cases.  Tim Starling 06:50 Apr 1, 2003 (UTC)
Ghitis  your new definition did not use standard physics language, so I reverted it. The electric field is a very welldefined concept in physics, and 'spatial manifestation' and 'material entity' are not. Tantalate 19:57, 26 Aug 2004 (UTC)
I think that both forms are important and that unless there is a good reason not to, the equations should look more like : Most, if not all advanced E&M textbooks include both, and with good reason: there are times when each is advantageous over the other. Scott
 I second this, as a brief look at the history shows that people have been twidling the to periodically, not realizing that already is a unit vector. —The preceding unsigned comment was added by 128.61.117.118 (talk) 02:35, 11 February 2007 (UTC).
In my opinion, the most definite and illustrative formulas for the electric field are for the set of point charges and for the continuous charge distribution. These forms emphasize the fact that the field is determined at the point and is caused by either charged particles at points or the charge density in all points in the volume . These formulas were used in the book on electromagnetism by Grant and Philips. What do you think? Do they look too complicated? Jmattas 09:58, 8 August 2007 (UTC)
 Ah, Jmattas, that's exactly the form I was looking for, myself. I am struggling through reviewing from a textbook I haven't read in a long time (Griffiths' Introduction to Electrodynamics), and your "illustrative formula" reminded me that my professor simply never used Griffiths' "script r" but instead always used its definition: "script r" = .
 Now, you ask if it looks more complicated using that in the formulas... I'm not sure. Something must be done to ensure the greatest clarity, and I liked Scott's idea of showing two forms of the same expression, because it is indeed true that there are different reasons to use each one. Qrystal 22:22, 18 September 2007 (UTC)
Efield
Efields are just mathematical abstractions? No. Since the time of Maxwell we have known that efields and bfields are two facets of electromagnetic fields and they contain electrical energy. E. g., if a positive charge is pulled away from a negative charge, energy is stored in the surrounding efield pattern. (A mathematical abstraction cannot store electrical energy!) In modern QM and Gauge theory, we regard the classical fields as being caused by photon exchange, both magnetic fields and electrostatic fields are "made" of photons.Wjbeaty 11:22, Feb 28, 2005 (UTC)
 Yes I agree, the article should make it clear that these fields are real, and are not just mathematical abstractions. Actually I have a great quote from a lecture David Griffiths (physicist) gave a little over a year ago (spring 2006) "[electric] fields are real, just like kangaroos!" Perhaps someone else might know how this idea should be injected into the article, and if you would like I can properly reference the quote later. Fieldworld 19:11, 24 March 2007 (UTC)
Is this ever called Efield? I would like to replace "In physics, an electric field or Efield" with "In physics, an electric field (also known as an electrostatic field)" since 'electrostatic field' is very common usage (I just saw it in the wikipedia requests and redirected to this page) Shameer 03:12, 14 Feb 2005 (UTC)
In physics, we always called 'em by the names "efield" and "bfield." The phrase "electrostatic field" has too many syllables for convenient use in heated latenight conversations! Search google for efield: 149,000 hits, while "electrostatic field" gets only 75,000 hits: [1]
 An electrostatic field is an electric field that doesn't change with time, it's not a synonym.  Tim Starling 01:51, July 22, 2005 (UTC)
Mathematical Fields are only models of the physical world
=============================================
For well over 100 years now scientists have been raised to believe that real world stuff can be defined to BE a mathematical models. Example from this article: "The electric field !!! IS !!! a vector field". Wether or not this phenomena IS photons or IS something else from the real world is irrelevant (I personally believe it's a property of spacetime just as curvature is). It is, as the above writer states, "as real as kangaroos" and definitely not a "vector field" which is a mathematical invention nowhere to be seen in the real world. This definition and (many others) need to be changed to something like "a phenomena that can be mathematically represented as" a vector field. —Preceding unsigned comment added by 109.186.43.95 (talk) 18:22, 13 November 2010 (UTC)
Clarification please
An anonymous editor added some text [2] including the words:
 The above paragraph is perhaps misleading ...
This gives the impression that the article is arguing with itself. Can anyone think of a better way of putting it? The wording of that whole edit could be clearer. Thanks. Heron 2 July 2005 22:36 (UTC)
I have a question? I am researching this topic, because when I go through store security terminals especially when I have my cell phone the sensors go off. Also when I am sitting at a computer I feel energy. And different times throughout the day I feel webs of energy all over my body. I know as a human I am not a magnet, but I would like to discover what it is about me that is causing this?
I can be emailed at facingfuturehope@yahoo.com
clarification of terms
Please explain better the distinctions between the terms electric field, electric field intensity (magnitude of the electric field vector) (E) (V/m), electric field strength (vector quantity), electric field gradient, Efield, and so on. What are the units of each?  Omegatron 13:16, July 19, 2005 (UTC) I'm pretty new here, but I'm trying to help make the electromagnetics articles less messy and more readable. I notice there is a separate article (a stub) for electric field intensity. It should be removed, and instead pointed here, right? I'm adding mention of that term to this page, in addition to some other readability changes. Please let me know if I do anything bad! Xezlec
Okay, I went ahead and did the abovementioned redirect. This is ok, right? Xezlec 04:11, 31 December 2005 (UTC)
Sorry for continued nitpickery. I've now expanded the article to mention that a changing Bfield also produces an Efield. I revised some things to make it clear that most of the rest of the article applies only to the static case. I'm not sure the overall structure of the article is still "prettylooking" but at least it's more complete and more strictly correct now. Xezlec 06:45, 31 December 2005 (UTC)
I disagree with the use of the term "electric field intensity" in referring to the electric field vector. Traditionally the term intensity refers to the modulus squared of the electric field (or the square of the electric field strength to use the terminology in the article). Intensity is a scalar quantity, not a vector. Regards, Justin Hannigan.
Smythe's "Static and Dynamic Electricity" refers to E (the vector) as "electric field intensity". Also see Marion + Heald, p3, which calls it "electric intensity vector or electric field vector". Pfalstad 19:18, 26 September 2006 (UTC)
I agree with Justin Hannigan. The standard terminology is simply electric field.24.52.254.62 06:21, 3 November 2006 (UTC)
Derivation
The derivation takes up too much space, and shouln't be at the top. Not only that, most of that derivation is describing coulomb's law which should simply be linked to. I'll do that if noone objects. Fresheneesz 06:46, 3 May 2006 (UTC)
The permittivity of a vacuum is not 'usually 7'. I'm removing that from the Coulomb's Law section. MrDeodorant, December 15 2007 —Preceding unsigned comment added by MrDeodorant (talk • contribs) 04:42, 15 December 2007 (UTC)
list of Efields due to common charged surfaces
I think it would be very useful to have a small list of the Efields of charged surfaces, like spheres, cylinders, wires, etc. Fresheneesz 19:13, 10 May 2006 (UTC)poopp
change to first line
The first line read that an E field excerts a force on "objects" i put in "electrically charged" infront of objects, since this is more correct. An object wont feel a force from an E field unless it is charged itself. Robertirwin22 20:11, 13 May 2007 (UTC)
B
I notice that Special:Contributions/83.131.29.96 has changed magnetic flux density to magnetic field in a number of articles. I am conscious that a blanket reversion could antagonize, but magnetic flux density would seem to be correct in this case. It would facilitate discussion if this user acquired a name. Incidentally, I would agree that the distinction between flux and field could disappear in more advanced treatments using some system of natural units (and in the historical emu system? (I forget)). However, the fact that this article is called Electric field, and not say electromagnetic tensor, suggests a more elementary approach is appropriate. catslash 17:56, 7 July 2007 (UTC) hhkjhhgjhighgjih — Preceding unsigned comment added by 12.218.113.146 (talk) 18:01, 12 October 2012 (UTC)
Uniform electric field
Someone created the page Uniform electric field. I don't think we need a page like that. What do you think? Should it be deleted? Merged with this page? Or expanded into a full article? (What would it talk about?) Coppertwig 21:29, 20 September 2007 (UTC)
Template:Electromagnetism vs Template:Electromagnetism2
I have thought for a while that the electromagnetism template is too long. I feel it gives a better overview of the subject if all of the main topics can be seen together. I created a new template and gave an explanation on the old template talk page, however I don't think many people are watching that page.
I have modified this article to demonstrate the new template and I would appreciate people's thoughts on it: constructive criticism, arguments for or against the change, suggestions for different layouts, etc.
To see an example of a similar template style, check out Template:Thermodynamic_equations. This example expands the sublist associated with the main topic article currently being viewed, then has a separate template for each main topic once you are viewing articles within that topic. My personal preference (at least for electromagnetism) would be to remain with just one template and expand the main topic sublist for all articles associated with that topic.DJIndica 16:31, 6 November 2007 (UTC)
Speed of propagation for gravity
 Comparing gravity with electrostatics, the article states that "both propagate with finite speed c." Is there a reference for this? As far as I know in the Newtonian mechanics gravity propagates instantaneously? If so this statement needs to be put under differences. Zeyn1 (talk) 20:22, 26 April 2008 (UTC)
 General relativity, which supersedes Newtonian mechanics, predicts that gravity propagates at c.  Eldereft ~(s)talk~ 01:07, 27 April 2008 (UTC)
 The article states that we are talking about the similarities between electrostatics and Newtonian gravity: "Coulomb's law which describes the interaction of electric charges is similar to the Newtonian gravitation law." So the statement "both propagates with finite speed c" means that Newtonian gravity propagates with the speed of light. The article on the speed of gravity is clear that Newtonian gravity is instantaneous. I propose that this item be moved to the differences between electrostatics and Newtonian gravity. Zeyn1 (talk) 16:58, 29 April 2008 (UTC)
SI base units in introduction
I added the SI base units to the introduction because I feel it would improve the article. Any objections? Bdforbes (talk) 21:26, 21 November 2008 (UTC)
A
In the definition (and in the entire article), A is not defined and I do not understand what it stands for. I think this should be explained. Arnaud Dessein (talk) 12:42, 16 March 2009 (UTC)
Units
The article gives the unit for electric fields as Zoids. I can find no reference to this as a unit of measure equal to N/C. —Preceding unsigned comment added by Omicron84 (talk • contribs) 02:10, 17 May 2009 (UTC)
It was posted by "Zoidfather", the "Zoid" is not a unit of measurement and appears to have been spam. I've removed it. Hungryhungarian (talk) 17:32, 21 May 2009 (UTC)
The unit
I'm not an expert on dimensions. But I think the kg·m·s^{−4}·A^{−1} unit needs to be revised. Nedim Ardoğa (talk) 08:10, 13 July 2009 (UTC)
Whatever the dimensions of electric field may be, the SI UNIT is volts/metre. Please correct this .. Andrew Smith —Preceding unsigned comment added by 82.32.50.77 (talk) 10:23, 3 January 2010 (UTC)
 At the beginning of the article, I see both N/C and V/m listed as equivalent SI units for electric field, which is correct. Is there somewhere else where the wrong SI units for electric field are given? CosineKitty (talk) 15:23, 3 January 2010 (UTC)
Definition?
It is very misleading to begin this article with a definition in terms of potentials. Historically, the electric field was seen as an abstraction of the electric force, and the most intuitive definition was through the formula F = q E for static fields. Topics such as elementary particles and vector potentials should be left our or included only parenthetically. 146.6.178.202 (talk) 17:24, 8 September 2009 (UTC)
Fundamental Error in the calcul of Energy of Efield
By Heldervelez: The 'fathers' of electrodynamics believed in an infinite universe in time, but we know now differently. The integration extended to ALL space is incorrect. One can only integrate inside the lightcone, and the Efield energy becames a time growing value, instead of a constant one. To preserve the energy of the entity particle+field the mass of particle must decrease thru time. The killing error is presented here: and discussed at BautForum ATM Links to a new model of the universe based on 'Evanescence' is also presented there. I'm willing to make a reference to this claim as Controversy. Any ideas ? —Preceding unsigned comment added by Heldervelez (talk • contribs) 18:35, 24 September 2010 (UTC)
This article is BLECHH...
Main changes:
 "Therefore an electric field is defined with respect to a particular configuration of source charges." < Correct.
 "In practice, this is achieved by placing test particles with successively smaller electric charge in the vicinity of the source distribution and measuring the force exerted on the test charges as their charge approaches zero.
 This allows the electric field to be determined from the distribution of its source charges alone." < This is simply a meaningless definition that I have yet to see in use anywhere (feel free to contradict with examples). No suprise there is no referance. Why take the limit that charge becomes zero when E is force per unit (positive) charge?? Just how does it define the electric field as a config of charges when there is no dependence on position?? All that needs to be said for a defining equation is , where q is a test charge, not a source charge Q. Using Colombs law, the E field due to the source charge Q is . I have also changed the obscure notation "q_{t}" and "q_{s}" to be the simpler and more common q, Q.
 The volume integral looks painfully vague
 Clean up the equations
 Rewrite for less wordy prosy sentences, made them to the point, remove a lot of repetition
 Resection in places
 Moved the current "referances" into the external links and replaced referances with proper books on electromagnetism.
For those that wrote the article and who I may be insulting: don't get me wrong  its good to add external links and try etc, but better to use secondary sources more than primary. =)
 F = q(E + v × B) 01:16, 28 February 2012 (UTC)
Changes
I reverted these [3] changes as they appear to move away from standard notation. IRWolfie (talk) 13:16, 9 July 2012 (UTC)
Electrostatic fields section
I've been looking at the section on electrostatic fields, and it is quite messy. Equations seem to be presented out of order (or at least the descriptions of them are out of order). Also, there is an equation derived from Coulomb's Law that is simply in the text and not explained in any way. I don't know where to start to rewrite this section, but it definitely needs some work. K of slinky (talk) 14:28, 10 July 2012 (UTC)
what is the electric field
electric field is area of charge, whare another charge partical expirinced the force of atreaction or repeltion. — Preceding unsigned comment added by 101.215.149.52 (talk) 03:20, 15 October 2012 (UTC)
Use of Theta for Electric Potential
I noticed repeated use of the capital letter theta for electric potential. Besides the fact that I've only seen potential represented by V, I found that the Wikipedia article on potential does not use this notation either. I believe this notation may confuse people who usually see electric flux represented by theta. Does anyone know why this letter may have been used here in this context? ~Username222 (talk) 01:05, 29 January 2013 (UTC)
First two sentences
The first two sentences here read:
An electric field surrounds electrically charged particles and timevarying magnetic fields. The electric field depicts the surrounding force of an electrically charged particle exerted on other electrically charged objects.
I'm curious, what language is that? It has some superficial resemblance to English, but lacks the crucial characteristic of communicating meaning to others who speak the same language. Would someone with some fundamental understanding of the basics of the topic perhaps like to write a couple of sentences that lay out clearly what an electric field is? I believe that would make a good opening to an article on the subject. Just to be clear, we don't need to know what it surrounds (how does it know where the limits of the "timevarying magnetic fields" lie, by the way?), or what it depicts; but it'd be really handy to know what it actually is. Thanks, Justlettersandnumbers (talk) 00:31, 16 July 2013 (UTC)
 I agree. I've reworded it a bit – still not perfect, but hopefully better. — Quondum 02:39, 16 July 2013 (UTC)
 Thanks; and yes, I believe it is improved. What I would like to see there and do not have the background to write myself is a simple statement in very plain English of what an electric field is. It seems to me that if the opening sentences of the Qualitative description were simplified, they might fulfil that function. It's a vector field; it represents the magnitude and direction of the force that would be felt by a unit charge placed at each point within it ... but, as must be obvious, I don't have the background. I may be way off here, but it's my feeling that the first few sentences in this sort of article should be accessible to the general reader, with the technical stuff coming further down the page. I should also apologise for the unduly scorbutic outburst above. Justlettersandnumbers (talk) 00:10, 18 July 2013 (UTC)
 You are quite correct: accessibility in the lead should be striven for, and in this case should not be too difficult to achieve. And you communicated the shortcoming quite effectively; I found it quite humorous, especially when reading the mangle of words in the quote. It is all in the interests of improving Wikipedia. — Quondum 02:42, 18 July 2013 (UTC)
 Thanks; and yes, I believe it is improved. What I would like to see there and do not have the background to write myself is a simple statement in very plain English of what an electric field is. It seems to me that if the opening sentences of the Qualitative description were simplified, they might fulfil that function. It's a vector field; it represents the magnitude and direction of the force that would be felt by a unit charge placed at each point within it ... but, as must be obvious, I don't have the background. I may be way off here, but it's my feeling that the first few sentences in this sort of article should be accessible to the general reader, with the technical stuff coming further down the page. I should also apologise for the unduly scorbutic outburst above. Justlettersandnumbers (talk) 00:10, 18 July 2013 (UTC)
can we add that electric field is a model in physics that represent the medium in which charged particles can apply force to each other? because even though electric fields represent natural behavior extremely well the electric field itself does not exist, it an mathematical model. kfir 09:15, 10 September 2013 (UTC) — Preceding unsigned comment added by Comixdude (talk • contribs)
 To say the electromagnetic field does not exist is not correct in the modern way of thinking about it, and the elecric field is a component of this. You seem to feel that it is really just an action at a distance (much like Newton's concept of gravity), but it exists as a physical entity as much as anything else does. Ask yourself: does light exist? So it is not that clear what you really want. — Quondum 19:49, 10 September 2013 (UTC)
The lede problems above are not the half of it
There exists an article called electromagnetic field. And yet another called electromagnetism that describes the EM interaction (the EM fundamental force).
So what are these articles about the electric field and the magnetic field? They are just articles about the electromagnetic field when seen by a privileged observer one who misses one field component because he's positioned just right in space and time.
That's like looking at a cube from JUST the right angle to see a square, where any other place when show you a 3D object. There isn't any PLACE that "has" an electric or magnetic field. Because any observer at such a place simply needs a velocity and will no longer see a pure E or B, but a mix. So it's both a place AND an inertial frame that seems to have just one field. So even though you can imagine an E field in a given place and frame, if you move, it's all screwed up and now you have both E and B.
There is an analogy with kinetic energy: if you hold position with regard to an electron, you will just its E field. And you ALSO will see no kinetic energy of the electron. But if it moves, or if it stays the same place but YOU move, you will no longer see just an E field, but now you see a new B field, and (moveover) also see that your electron "has" kinetic energy.
So is a "pure" E field "real"? Is it even worth the long discussion here? If the E field from a distant particle is no more real than the kinetic energy of that distant particle (which comes and goes, depending on how you look at it, and what frame you look at it), then how real is that? SBHarris 05:42, 31 July 2013 (UTC)
 I tend to agree − there are a number of articles in this group of articles that should be merged into fewer articles. The current state is rather confusing, with heavy overlap in content. Maxwell's equations and Magnetism are others in the group. — Quondum 11:32, 31 July 2013 (UTC)
electric field
The electric field is a vector field. The field vector at a given point is defined as the force vector per unit charge that would be exerted on a stationary test charge at that point. An electric field is generated by electric charge, as well as by a timevarying magnetic field. Electric fields contain electrical energy with energy density proportional to the square of the field amplitude. The electric field is to charge as gravitational acceleration is to mass. The SI units of the field are newtons per coulomb (N⋅C−1) or, equivalently, volts per metre (V⋅m−1), which in terms of SI base units are kg⋅m⋅s−3⋅A−1 — Preceding unsigned comment added by 122.144.124.104 (talk) 03:15, 12 December 2013 (UTC)