1
$\begingroup$

If I have a magnet, which of the following is really called magnetic pole and why?:

$(1)$ Half of the volume of the magnet - north pole, other half volume - south pole.

$(2)$ Area at one end of the pole - north pole, area at other end - south pole

$\endgroup$
2
$\begingroup$

Draw yourself a picture of a cylindrical bar magnet, with the field lines emerging from one end, looping around, and entering the opposite end to connect up with the emerging lines again. the poles of the magnet are those zones near the ends where the field lines begin to diverge as they near the physical end of the magnet. This places the pole at each end roughly one bar diameter inboard of the bar's end.

$\endgroup$
  • $\begingroup$ can you give a reference to that definition of the pole? $\endgroup$ – N.G.Tyson Sep 7 '18 at 8:31
  • $\begingroup$ it's a casual definition I got from a physics book a very long time ago, when I was studying magnets and trying to figure out what exactly was going on at the poles of a magnet. I do not know if there is a "formal" definition. $\endgroup$ – niels nielsen Sep 7 '18 at 16:40
0
$\begingroup$

The north pole is where the field lines leave and the south pole is where they enter. For a current loop the two coincide: it is the surface or any surface enclosed by the loop. For a piece of magnetised iron it is conventionally the material surface.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.