Talk:Magnetic field density

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[edit] Suggestion to merge articles

I propose this is merged with "Magnetic Field"; they are the same units and come from the same idea.

I strongly disagree with the suggestion to merge this article with magnetic field. These are two different, though related, concepts. For starters, the two have different units of measures (dimensional decompositions). Magnetic field is amps per meter, magnetic flux density is webers per square meter. -- Metacomet 15:08, 31 January 2006 (UTC)

The article magnetic field discusses in detail both fields B and H. Therefore, there is no reason to have a separate article discussing B. (The units of B and H are indeed different. But the units of B from "magnetic field density" and of B from the article "magnetic field" are the same, and this is exactly the same quantity). Yevgeny Kats 17:12, 31 January 2006 (UTC)

In my opinion, there should be an overview article that discusses both B and H, including high-level definitions, differences between the two, and the relationship between them. Then there should be two separate, more detailed articles, one article on each of the two fields. For historical reasons, and because of the way electromagnetics is often taught in introductory courses, there is a lot of confusion between B and H. It would be a shame if WP were to reinforce the confusion, instead of trying to clarify the distinction and explain where it comes from. Again, these ideas are simply my opinion. -- Metacomet 17:28, 31 January 2006 (UTC)

As a suggestion, the three articles might be called:

• Magnetic field (overview) to give high-level overview
• Magnetic field intensity to give detailed discussion of H
• Magnetic flux density to give detailed discussion of B

-- Metacomet 17:33, 31 January 2006 (UTC)

[edit] About the left-hand rule

This picture from the article illustrates the left-hand rule, which is used for determining the direction of the magnetic force F for a given magnetic field B and an electric current I. But this rule could only be applied to the very special situation when the three vectors F, B and I are all perpendicular to each other. I think it is important to provide the general expression with cross product, which could be apply to general situations even if F, B and I are not perpendicular to each other. Should we add that to the article? It seems that the German version of the article is doing a pretty good job on that. We can have some reference on the German version. - Alanmak 23:41, 12 February 2006 (UTC)

This diagram seems to show the thumb in a parallel direction to the middle finger, whereas it should be perpendicular both to the index finger and the middle finger--Light current 01:09, 25 April 2006 (UTC)