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I am trying to understand electromagnetism. I would like to pare myself down to the minimum number of necessary concepts.

From my physics education (high school only), I understand that a moving charge creates a magnetic field. The implication is that magnetism is a discrete concept that I also need to understand.

However, is this view actually confusing: is it the case that a magnetic field is a moving charge?

Either way, a link to a primer accessible to someone with a engineering degree level maths would be wonderful. If it is the case magnetism is a moving charge, then an introduction following this approach would be wonderful.

Thank you!

Benjohn
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    I found A Student's Guide to Maxwell's Equations to be a good introductory book. – John Rennie May 01 '14 at 16:29
  • Thank you for the link @JohnRennie. I'll grant my maths is a little rusty, but the cover alone is fairly intimidating, unless there's a gentle run up to the notation used there :-) – Benjohn May 01 '14 at 16:33
  • The problem is that you can't understand magnetic fields without understand Maxwell's equations - at least in principle if not in all their gory detail. You say magnetism is a discrete concept but it isn't. An electromagnetic field can appear as an electric or magnetic field depending on your frame of reference. For the small investment required I would buy the book and have a quick scan through skipping the maths. That will at least give you a starting point. – John Rennie May 01 '14 at 16:45
  • Hi Benjohn, what would you say is 'engineering degree level' mathematics. Are you comfortable with calculus? – Danu May 01 '14 at 16:50
  • @JohnRennie The book sounds good, I'll take a look. Thank you. – Benjohn May 01 '14 at 16:52
  • @Danu I'm comfortable with integrals & differentials, which I believe is calculus? – Benjohn May 01 '14 at 16:54
  • @Benjohn how about vector calculus? – Danu May 01 '14 at 16:57
  • @danu At first look, I'm comfortable with Wikipedia's page on vector calculus up to the mention of Curl under "Differential operations", which makes some intuitive sense. The "Theorems" section looks scary. – Benjohn May 01 '14 at 17:08
  • @Benjohn I would recommend a standard introductory book on electrodynamics (Griffiths' book Introduction to Electrodynamics is the standard in physics curriculums), the first sections will typically offer a concise summary of/intro to vector calculus; you could use one of the standard calculus books which should all cover both single- and multivariable fundamentals to supplement your readings – Danu May 01 '14 at 17:13
  • I found this related question to which the second answer states "magnetism is nothing more than electrostatics combined with relativistic motion", which lead me to Wikipedia's Relativistic Electromagnetism article, which makes a reasonable amount of sense to me, although I can't see why a stationary charge wouldn't deflect away from the wire instead of staying still. – Benjohn May 01 '14 at 17:46
  • The down-vote seems a little harsh. If this SA is for Physics practitioners, rather than the curious, I'll take it on the chin :-) – Benjohn May 01 '14 at 17:50
  • @Benjohn: I wouldn't pay too much attention to the down vote, there are some miserable beggars lurking on this site (though most of us are quite nice - I think :-). Have a +1 from me to counteract it, anyone who is willing to learn electrodynamics needs encouragement! – John Rennie May 01 '14 at 18:31
  • @JohnRennie Thanks! :-) Reassuring to know I'm not doing anything too stupid. – Benjohn May 01 '14 at 19:27

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