Differential Equations Describing Magnetic Fields Around Magnets

AI Thread Summary
The discussion focuses on the differential equations that describe the magnetic field around a magnet, particularly emphasizing the field of a magnetic dipole. The magnetic field can be expressed in vector notation, with a specific equation provided for the field's behavior at distances far from the magnet. Participants note technical issues with displaying the mathematical notation, suggesting that the browser may not be rendering it correctly. One user points out a potential error in the formatting of the equation. Overall, the conversation highlights the relationship between differential equations and magnetic fields while addressing technical difficulties in communication.
EroticNirvana
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The magnetic field around a magnet very much looks like the solution of a differential equation (which I guess it is, at least apprx). Now, can anyone give my a few simple exaples of such differential equations describing a magnetic field around a magnet?
 
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If you are not too close to the magnet, the field around it is the field of a magnetic dipole {\bf m}. In vector notation, the magnetic field is given by
[tex{\bf B=-\nabla\left(\frac{\bf m\cdot r}{r^3}\right)
=\frac{3({\bf m\cdot{\hat r}){\hat r}-m}}{r^3}.
[/tex]
 
Last edited:
browser malf?

i see only strange symbols in the above msg. Does my browser not work properly?
 
{\bf B=-\nabla\left(\frac{\bf m\cdot r}{r^3}\right)<br /> =\frac{3({\bf m\cdot{\hat r}){\hat r}-m}}{r^3}.<br />

I think he forgot to close a ] around the tex notation. :)
 
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