Help illustrating magnetic field line vectors and gradients

AI Thread Summary
Magnetic field lines around multipolar magnets exhibit complexity, particularly in the context of a centrally charged disc magnet. The discussion includes critiques of provided illustrations, highlighting inaccuracies in the representation of magnetic field lines, which are supposed to be continuous with no beginning or end. Experts emphasize the importance of distinguishing between magnetic field vectors (B) and magnetic field intensity (H) in diagrams. The illustrations presented are considered less accurate than typical textbook representations, with a reference to Sommerfeld's work for better examples. Accurate representation of magnetic fields is crucial for understanding their behavior and properties.
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Magnetic field lines around multipolar magnets get quite complex. There are local field vectors and field gradients in the x, y, & z plane. In the following diagrams I have tried to illustrate field lines around a centrally (half and half) charged disc magnet. The top diagram represents the field lines and the bottom the field gradients in the xy plane (assuming the xy plane in parallel to the surface and the z plane perpendicular).

I would love for learned PF magnetism experts to critique these illustrations. Thank you.
FieldLines-Zaxis2.jpg

(I realize the colour of these field lines be swapped on the bottom)
FieldLines-XYaxis2.jpg
 
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magnetics said:
I would love for learned PF magnetism experts to critique these illustrations.

Magnetic field lines have no beginning or end. Your drawings show the opposite.
 
Where are these drawings from? They are even worse than the usually not very accurate field-line pictures even in textbooks. Very good ones are in the good old book by Sommerfeld:

A. Sommerfeld, Lectures on theoretical physics, vol. 3 (electromagnetism)

Particularly you have to properly distinguish between ##\vec{B}## and ##\vec{H}## lines!
 
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