Triangular magnets

[Tres Juicy]

Hi all,

 

Just a quick one, what happens when you cut a magnet along its length so that one pole has less volume/mass than the other?

 

Would the thinner pole just be weaker or would the whole thing re-align?

 

I'm thinking that it would shift the poles so that the point is somewhere in the middle, sort of "sharing out" the weak point between the two poles

 

Can anyone enlighten me?

 

Thanks,

 

Al

[Schrödinger's hat]

If you cut a magnet, you wind up with two smaller/weaker magnets.

The best way to think of it in order to not get confused is this:

Imagine the magnet being made of many tiny magnets. If they align the magnetic field adds up to a stronger field.

 

So if you cut your big magnet, the tiny magnets still line up and add up.

If you were to then rotate one of the pieces, some of the tiny magnets would produce the opposite field to the others, so the net effect would be much weaker in most places (not zero because the strength also depends on distance).

[Tres Juicy]

If you cut a magnet, you wind up with two smaller/weaker magnets.

The best way to think of it in order to not get confused is this:

Imagine the magnet being made of many tiny magnets. If they align the magnetic field adds up to a stronger field.

 

So if you cut your big magnet, the tiny magnets still line up and add up.

If you were to then rotate one of the pieces, some of the tiny magnets would produce the opposite field to the others, so the net effect would be much weaker in most places (not zero because the strength also depends on distance).

 

Sorry, my question is not clear enough.... my fault

 

"If you cut a magnet, you wind up with two smaller/weaker magnets."

 

I know ... What I'm asking is this:

 

 

Take a rectangular magnet and trim down the north pole to a point (creating an isosceles triangle) throw away the other bits so you are left with One triangular magnet.

 

Now, if the north pole is much thinner than the south is this sustainable?

 

Will the now much larger south pole overpower the weaker north? A kind of quasi-monopole? (surely not possible)

 

Or will the field re-align itself to "balance" this out?

 

Thanks

[Schrödinger's hat]

Very loosely, it'd have north pole all the way up the angled surface.

Or you could model it as a bunch of magnets of different lenghts/strengths all side-by-side.

[Tres Juicy]

Very loosely, it'd have north pole all the way up the angled surface.

Or you could model it as a bunch of magnets of different lenghts/strengths all side-by-side.

 

 

Ah... so the lines of force won't change direction and the field won't change shape in any meaningful way

 

That makes sense

 

Thanks SH

[Schrödinger's hat]

Well it'll change shape a bit, but still loosely resemble that from a bar magnet up close, and very closely resemble it from a distance.

[aristosteles]

i dont know the terms butiwill link you  a   link to a set of images with magnetic-fields  my.execpc.com/~rhoadley/gallery/imageset.html

[DrP]

8 minutes ago, aristosteles said:

i dont know the terms butiwill link you  a   link to a set of images with magnetic-fields  my.execpc.com/~rhoadley/gallery/imageset.html

   Hi/welcome aristosteles.   I am not sure if the OP is active anymore - he hasn't posted since early 2016. This thread is about 6 years old too.

[aristosteles]

well im just doing my duty if he replays good if not is his loss

 

[DrP]

 

Doh - I tried to link to the pic where they sliced the magnet to make two triangles as described...  but it has just linked the whole page again   -  The pic is in there though.

Sorted it out - I guess this is the one the OP was talking about. (or close enough).

 

Edited November 21, 2017 by DrP