0
$\begingroup$

If the electron flow in a magnet is say from South pole to North pole, then I can understand why you can't put the two north ends of magnets together, as the two flows of electrons repel each other.

But then why can't I put the two south pole ends of a magnet together? If the electrons flow out the North pole and into the south pole, then what force is repelling the two south poles??

If the answer is to say there are two electron flow, in opposite directions, then why don't they just cancel each other? There must be "something" else flowing in the opposite direction of the electrons that causes the two south poles to be repelled.

Edit:

Perhaps electron flow was bad choice of words. Every diagram of a magnet I see shows the lines of flux flowing from out of North pole and into South pole. Given this flow of "whatever", it is easy to understand why the North poles would repel each other. It is also easy to understand why the North pole of one magnet is attracted to the South pole of another. My question really is why do the South poles also repel each other? If the magnetic field is really flowing "into" the south pole, then what force causes the two South poles to Repel each other.

$\endgroup$
  • 2
    $\begingroup$ electron flow in a magnet is say from South pole to North pole This doesn't seem to make sense. $\endgroup$ – jinawee Jun 7 '14 at 20:47
  • 4
    $\begingroup$ Permanent magnets aren't a current loop. The electrons spins are aligned. $\endgroup$ – Brandon Enright Jun 8 '14 at 0:15
  • 1
    $\begingroup$ You are imagining these flux lines as jets of water shooting out of north pole and entering south pole. This is wrong! $\endgroup$ – Rijul Gupta Jun 8 '14 at 7:37
1
$\begingroup$

The flux line direction at a point $P$ is defined (by convention) as the direction pointed by the N end of an infinitesimal "test compass" placed at $P$. There is no "magnetic goodness" emanating from N and sucked into S.

$\endgroup$
0
$\begingroup$

Forget the term "Magnetic Lines of Flux" - this is confusing. Imagine a magnetic field as a uniform curvature of space-time, similiar to gravity except only a part of 'sub space' is affected - (the part that electrons occupy). The north pole is space bending in one direction, the south the inverse shape. Space-time hates these perturbances - it would rather space just be 'flat'. When you try to put 2 like poles together, you are trying to increase the perturbance, so space-time resists. Opposite poles cancel out the bend in space between the poles joined, so space-time pushes the magnets together. Attempting to separate the magnets again is met with resistance, you are trying to re-instate the two perturbances that exist on each pole. So it's space-time itself that applies the forces!

$\endgroup$
0
$\begingroup$

Nothing flows along magnetic field lines. They are just a mathematical construct to help visualize the field. At each point along a field line, it is parallel to the magnetic field.

Most of the magnetism in a permanent magnet comes from electron spins, not the movement of electrons. Spin is a fundamental property of elementary particles, a purely quantum mechanical phenomenon. In solids with a magnetic ordering such as ferromagnetism, the spins are aligned enough to produce a net magnetic moment.

As for why two south poles or north poles repel while opposite poles attract, there is a famous interview with the physicist Richard Feynman in which he says, "I can't explain that attraction in terms of anything else that's familiar to you." It's just how magnetism works.

$\endgroup$

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.