Talk:Dielectric
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[edit] Beginner's Corner
Hi, I've deleted nothing, but added an overview called "Beginner's Corner." The idea is to draw a wider readership into the article. The ploy is reaching for relationships to observations or knowledge the not-so-technical reader already has. We're not dumbing down here, we're reaching out. Hopefully some new readers will want additional rigor and find it right here in the more "Wiki classic" parts of the article. I can be aroused from slumber at jerry-va at speakeasy dot net. Jerry-VA 01:46, 7 September 2006 (UTC)jerry-VA
how does dielectric constant vary with temperature?
Depends on the material. How long is a piece of string.--Light current 03:16, 27 January 2006 (UTC)
[edit] Electric and magnetic fields- whats the difference?
If the presence of a dielectric (E >1) can distort an electric field, does the presence of a ferromagnetic material (U>1) distort a magnetic field from a magnet. If so, what do iron filings do to the magnetic field when spread around a bar magnet? 8-?--Light current 00:12, 4 May 2006 (UTC)
[edit] Definition
I have made a correction to the definition of a dielectric in the introduction. Also, I excised this paragraph which is both poorly-phrased technically and somewhat misleading.
Electrically, the dielectric constant is a measure of the extent to which a substance concentrates the electrostatic lines of flux. More specifically it is the ratio of the amount of electrical energy stored in an insulator, when a static electric field is imposed across it, relative to vacuum (which has a dielectric constant of 1). Thus, the dielectric constant is also known as the static permittivity.
- Yeah I noticed. I put it back. Rewrite if you wish, but lets keep the info 8-)--Light current 19:55, 28 July 2006 (UTC)
Can somebody explain what this means:
The presence of a dielectric concentrates the applied electric field (e-field) within itself.
- Can you please sign and date your posts by typing ~~~~ . THanks. THen we can talk--Light current 12:32, 29 July 2006 (UTC)
Well, the article's wording probably could be changed to be a bit clearer. When a dielectric with a relatively high dielectric constant (k) is immersed within a uniform electrical field (i.e., within free space or within another dielectric having a lower dielectric constant), the shape of the E-field near the dielectric becomes distorted. In the case of a dielectric sphere or cylinder, the nearby E-field lines are "attracted" to, and concentrated within, the dielectric material. Similarly, if the sphere has a lower dielectric constant than its environment (i.e., an air bubble in oil), the E-field will tend to avoid the sphere, preferring instead to flow around it. Discussions, including images showing the effect on E-field lines for higher and lower k spheres and cylinders can be seen at [1] and [2]. A more general discussion, including a description of a conductive sphere in a uniform field (E-field always normal to the surface), can be found at [3] Bert 14:28, 29 July 2006 (UTC)
[edit] Extermal link on dielectric properties of polymers
I added an extermal link on dielectric properties of polymers. I had this there before but in html so it had some marketing-ese in it and it got deleted. I found the .pdf so now it is all technical. I know it would be great to include some of the ideas and then just link but I can't do that (not enough experience in this area.) Hope this is OK Rsteif 15:48, 13 December 2006 (UTC)
[edit] Static Permittivity = Relative Permittivity?
"also called the static permittivity or dielectric constant εs"
Does anybody else realize that this is whack? Click the link for dielectric constant, and you'll be linked to an article that includes a phrase "also known as relative permittivity". So... by somebody's logic... static permittivity = relative permittivity. Sweet.
Also, if there is some technicality here that I'm not understanding, perhaps there needs to be some sort of disambiguation going on that might clarify the relationship between these two quantities.
69.156.153.12 01:08, 28 February 2007 (UTC)
I read a little more, and I realized that the Dielectric Constant article is referring to a "relative dielectric constant"... perhaps that needs to be disambiguated.
