Talk:Helmholtz coil

Comments[edit]

As stated by User:Michael_Hardy the page Helmholtz coil should be merged with Helmholtz Coils. I create the page Helmholtz Coil following a link from requested page.

I do not know now what is the correct name to use.

Helmholtz Coils is not correct that the second word is uppercase.

The rules state that singular is to be preferred unless the word is generally plural in English (like scissors).

Now in English the word coil exist in singular but only one coil in a Helmholtz coil is not enouth to make the system, so there no exit a Helmoltz coil in singular. A way of giving out of this problem would be to named the article Helmholtz coils system. But I do not like this solution. This name is never used in Physics.

For the moment I will merge Helmholtz Coils into Helmholtz coil and I will create a redirect from Helmholtz Coils to Helmholtz coil and another from Helmholtz coils to Helmholtz coil AnyFile 16:55, 17 Dec 2004 (UTC)

Who invented Helmholtz coils? The article states it was named 'in his honor'. I've searched the web to try and find an answer, but so far without success. DFH 18:51, 28 September 2005 (UTC)[reply]

Just checking on the math--if "n" represents the "number of coils," it is incorrect. Number of coils is denoted by "N" (the lowercase "n" means "number of coils per unit length"). Someone with more knowledge of the theory could change this, please. Ken 16:51, 26 May 2006

tag[edit]

someone add the tag for :article needs to be clarified or simplified.(cleanup?) — Preceding unsigned comment added by 66.31.197.38 (talk • contribs) 23:36, 25 April 2007‎ (UTC)[reply]

Contour plot is incorrect[edit]

Hi folks. The magnetic field contour plot is not correct - the field configuration shown there corresponds to two coils with reverse direction current; it's generated by quadrupole coils. I believe that Helmholtz coils are by definition set up with currents in the same direction. At the very least, I'm changing the caption to warn people that the plotted contours are for reverse-current coils. I'm working on replacing the picture with one for real Helmholtz field contours. --Bmk 20:45, 26 October 2007 (UTC)[reply]

Ah, sorry - I see now that the plot is of the magnetic field MAGNITUDE - sorry for the mixup - the plot looks fine. I undid my revision. --Bmk 20:48, 26 October 2007 (UTC)[reply]

Well, the countour plot is correct, but quite misleading. The field inside the "octopus" does have nearly constant magnitude, but the direction changes appreciably, especially in the "legs of the octopus", thus it is not homogeneous. A more appropriate quantity to be plotted would be the magnitude of the field error |ΔB| = |B- $B_{0}$ |=√{ $(B_{z}-B_{0})^{2}+(B_{r})^{2}$ }. The shapes of the contours are then much more realistic... — Preceding unsigned comment added by Zdeden (talk • contribs) 11:04, 25 January 2011 (UTC)[reply]

Incorrect or misleading terminology[edit]

In the UK the symbol B is used to designate the physical quantity known as 'Flux Density', measured in Tesla. The term 'Magnetic Field' is reserved for the quantity symbolised by H, and measured in amps/metre. Ambiguity can be avoided and correct technical language preserved if the terms 'Field' and 'flux density' are rigorously used when their precise meaning is intended. I think that this is a problem relating to differences in scientific terminology as used in the USA and Britain, but such differences should be minimised in a web article which has international availability. Another possible reason for use of confusing language in this context is that 'magnetic field' is itself ambiguous. It can mean either H (as described above) or, in more general discourse 'a region of magnetised space'. So great care is needed in using this term. Clearly insufficient care has been taken here -

'A simple calculation gives the correct value of the field at the center point. If the radius is R, the number of turns in each coil is n and the current flowing through the coils is I, then the magnetic flux density, B at the midpoint between the coils will be given by..'

where 'field' should be replaced by 'flux density'. Similarly, this caption to the contour plot is incorrectly worded, and the same substitution should be made.

'Inside the central 'octopus' the field is within 1% of its central value B0.'

—Preceding unsigned comment added by 82.32.50.77 (talk) 09:52, 5 June 2009 (UTC)[reply]

This is not correct. Magnetic field is a universal terminology. It is not correct to say it is a density; densities have units per-length or per-area or per-volume etc. I don't know why you think UK colloquialisms should be supported on wikipedia. SI unit of magnetic field is Tesla, represented by B. This is an international standard. — Preceding unsigned comment added by 128.54.75.211 (talk • contribs) 23:46, 26 January 2016

Requested move[edit]

The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section.

The result of the move request was: no consensus to move the page, per the discussion below. Dekimasuよ! 01:25, 14 October 2014 (UTC)[reply]

Helmholtz coil → Helmholtz Coils –

Proper terminology is "Helmholtz Coils", since there are two coils, not one. 129.252.70.97 (talk) 15:45, 6 October 2014 (UTC)[reply]
Lowercase 'c':: there are many such coils in the world, not one. Anthony Appleyard (talk) 04:58, 7 October 2014 (UTC)[reply]

Agreed, I don't believe that this is a proper noun.--199.91.207.3 (talk) 17:35, 8 October 2014 (UTC)[reply]

Oppose both issues. (1) The terminology is not fixed. Some sources use Helmholtz coil (e.g., Wolfram, "A Helmholtz coil consists of two circular coils of radius ....", http://demonstrations.wolfram.com/HelmholtzCoil/) and some sources say Helmholtz coils. Some websites use both HC and HCs interchangeably. (http://physicsx.pr.erau.edu/HelmholtzCoils/) To me, Helmholtz coil is precise and refers to a composite coil that consists of a pair of coils; each single coil is just an air solenoid with width and height much less than the radius; the orientation of the component coils is fixed; there isn't such a thing as a "single-coil Helmholtz coil". Well, http://www.phys.utk.edu/labs/Helmholtz_Coils_Uniform_Magnetic_Fields.pdf refers to "a pair of Helmholtz coils", but its title says "ROUGH DRAFT". See also WP's Maxwell coil (not "Maxwell coils" even though it consists of 3 coils) that is an improvement of the Helholtz coil. It would also be odd to say that a Maxwell coil consists of 3 Helmholtz coils. Using "Helmholtz coils" to refer to one instance has the same awkwardness as "scissors". (2) Agree that "Helmholtz coil" is a class and not a proper noun: compare Bailey bridge (a type of bridge) and Pegasus Bridge (a specific bridge in France). Glrx (talk) 20:48, 10 October 2014 (UTC)[reply]

The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.

Sources modified on Helmholtz coil[edit]

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Diagram labels[edit]

The diagram showing the dimensions of a coil pair shows two different dimensions both labeled `R`. The text describing the dimensions uses the letter `h` for one of these dimensions (the spacing between the coils), but that letter doesn't appear on the diagram. I understand that the text says for a Helmholtz coil, `h = R`, but for that statement to make sense, the diagram needs to include the `h`. I've no idea how such diagrams get edited, but replacing the upper `R` with `h` would improve the overall understandability. Burt Harris (talk) 16:59, 22 November 2020 (UTC)[reply]