Magnet mystery.

[kd0afk]

I bought some donut magnets to make a magnetic spring for a contact switch. The way they are polarized is so that one side is pos. and the other neg.. Funny thing is when one of them broke it changed into a curved bar magnet. The pie shaped piece that broke off has to be flipped over for it to be able to go back in place.
Here is a photo of the two sides.
How did this happen?

 

[Wagon173]

Because when it broke, it actually kept the same polarity. But since opposite poles attract in magnetics, you have to flip it over to make it stick to where it was originally. I'm sure there is a lot more scientific jargon to it than that, but that's what I sorta remember from high school.

 

[Sleazey]

Exactly right. When you break a magnet in half, you get two magnets.

Think of a plain old bar magnet, one end is N, the other end is S. when you break it in half, you don't get two monopole magnets, you get two dipole magnets.

That is, breaking a bar magnet (or any magnet) in half, you don't end up with a S only magnet and a N only magnet, you get two weaker normal magnets.

 

[kd0afk]

Pretty obvious when I think about it. Thanks.

 

[tomrux]

Nothing has flipped or changed. the analogy with a bar magnet being broken in half is where the confusion is coming from.

What you have done is take a piece out of the side of a magnet. so the poles have stayed the same: ergo it has to be filpped over to be attracted back where it came from.

Tom R

 

[Generatorgus]

Kind of like looking in a mirror???

In the mirror, how come your arms are on the wrong side but up and down are the same?

 

[kd0afk]

Kind of like looking in a mirror???

In the mirror, how come your arms are on the wrong side but up and down are the same?

You're arms are just where they should be left right up or down. The mirror isn't putting your left arm on the right side, its still there just perspective changes.

 

[tups]

The mirror isn't putting your left arm on the right side, its still there just perspective changes.

Actually the mirror reverses your image front to back, and since this is not a transformation regularly observed in our perception of the universe, we interpret it as "if I would walk to where (s)he is standing and then turn around, I would be left-right reversed". Your left arm is still on the same side as the mirror image's left arm. Just like the top of your head is still at the top in the mirror.

And about the magnet - if you put the piece back in place, but reversed, you will end up with an overall weaker magnet than it was before you broke it.

 

[bigo]

 

[flyingtractors1]

Interesting. With all of that in mind, a parabolic mirror can make one appear upside down - restoring right to right and left to left beyond the focal point. Or does it? But I've yet to see a mirror that will reflect your back when you look at it straight on. Ralph

 

[tornitore45]

TOMRUX got it exacly right, sorry but all others explanations are faulty.

The torus was originally magnetized face to face, in other words axially.

Reassembling the broken pieces forces N to N and S to S to be close and the pieces repel. Flipping does the opposite N to S and S to N the magnet is happy.

A broken long bar magnet would try to restore itself joining at the broken surface.