Orientation of sphere magnet inside sphere magnet

[magnO]

A sphere magnet inside a sphere magnet, both hollow, which of the two orientations will it prefer?

[magnO]

Why?

[JW]

Are you trying to make a compass or planing to make power. Also it is nearly impossible to machine these materials. 

[magnO]

Just interested in the theory, out of scientific exploration.

[JW]

The problem I see is that you need a magnetic bearing, and thats not possible with N-S-N-S  As to the magnetic field is going to attract were it can.   

[magnO]

I am not planning to build anything. I came across this forum via another website that mentioned it, it used some models that it had found in this forum, and thought I'd ask about how the magnets in the example will orient themselves. Perhaps it is the wrong forum, or, maybe it is the right forum since it is people genuinely passionate about electricity.

[MagnetJuice]

Very interesting question magnO. Welcome to the Forum.

I think that the positive pole of the sphere inside will seek the negative pole of the outer sphere, as in the second picture.

Could this be corroborated using the FEMM program?

Ed

[JW]

it used some models that it had found in this forum

if you can provide a way to reference to that, would be great. If you cant provide a "link" until 20 posts. Reach out to MJ via PM and Im sure he can post the link. Just finished up my mac and cheese and going to bed now

[magnO]

if you can provide a way to reference to that

nope, using guest mode in browser, no history record, so it is probably lost since I do not think I'll be able to remember specifically, I just followed the link to this forum

[magnO]

I think that the positive pole of the sphere inside will seek the negative pole of the outer sphere, as in the second picture.

That is what I've thought as well, and I had an electrical engineer say the same thing, comparing it to a two-pole induction motor. I had someone else say the magnetic poles on the inside of a sphere would reverse that on the outside, so that the inner magnet would orient itself like in example 1 in the image above, that the inner sphere is like an inner extension of the outer one, i.e. they should both have the same pole orientation. So, since just one of those ideas can be true, I'm trying to sort out which one.

[JW]

Is this what you saw?

https://www.fieldlines.com/index.php?topic=147030.0

Hope this helps

[magnO]

Nope, and it was not so much related to this question, so it is irrelevant in the context of helping or not helping. In fact, I believe it was you who was interested, not myself. I am still very interested in finding scientific consensus around how two concentric ring magnets would behave. What I mean by consensus, I have gotten contradictory answers, one crowd says that the alternative to the right in the image below is accurate (that is my intuition as well), the other that the poles on the inside of hollow spheres is reverse, the outer north pole is a south pole on the inside, etc, so that the alternative to the left is correct. I am, specifically, interested in which of those two is true, as both cannot be true. I lack the tools to test it myself experimentally, and I lack the theory to be absolute certain, so I turn to this forum, in the hope that someone with at least a moderate level of expertise could give a confident, definitive answer.

[Bruce S]

magnO

Before we go down the Moderator route
Please remember to try and be nice.
JW was probably trying to be funny, then got interested in what you were or are trying to figure out.

His link was a way to try to help , do not discount someone's attempt to try and help,  by calling it "irrelevant". All knowledge is relevant.

The sentence " In fact, I believe it was you who was interested, not myself." isn't correct either. You started this post therefore, it is you is interested. There are those of us who will also be interested in the outcome.

IF you have a way to check your browser's history, you can easily find the website you were on, that referenced this forum. That website could also be very interesting to us too. Even if you were on it as a guest, the area you were looking at will be still available .

For the most part; we all try to play nice here.

Bruce S

[magnO]

That is not to be nice, that is to be false. I am being honest, which is to be nice. The sentence " In fact, I believe it was you who was interested, not myself." is correct, very accurate. As I mentioned, the browser history is not recorded in guest mode on chrome, although I appreciate that you divert from the context of this thread. re: "Even if you were on it as a guest, the area you were looking at will be still available ." nope, the application, Chrome, does not work like that. I do not try to play nice, I actually am nice.

[JW]

I use google chrome it took me forever to have faith in. Just avoided as much as i could

https://www.fieldlines.com/index.php/topic,147030.msg1012229.html#msg1012229

[MagnetJuice]

To try to answer the original question, we need to consider how a hollow sphere would be made and magnetized. Where would the poles be?

I see two theoretical possibilities of constructing this spherical magnet:

1 – We start with a flat magnet that has the poles like this:


If we fold this flat magnet into a sphere we end up with a sphere that has one pole on the outside surface and the opposite pole on the inside surface. Like this:


This is interesting because if we place a smaller hollow sphere with opposite polarity inside this sphere, the small sphere will be suspended (floating) inside the large sphere. This will happen because the repulsion from similar poles.


2 – We start with a flat magnet that has the poles like this:


What would happen if we fold this flat magnet into a sphere? There are some people that say that the magnetism will be cancelled out once the ends of the flat magnet meet. But I believe that the magnetism will be contained within its walls. If we drill a hole into that sphere and place a steel nail in the hole, I believe there will be a magnetic force there.

Now let's consider another option of making a hollow sphere magnet. Manmade magnets are created by shaping the material (ceramic, neodymium mix, strontium, etc.) and then applying a strong current to the material for a short time. Once the current is removed, the material becomes magnetized and we have a permanent magnet.

Here we have a hollow sphere of magnetizable material and we apply a strong current like this:



Can someone tell me where the poles would be? And why?

Ed

[JW]

This is what I was eluding too when I mentioned a magnetic bearing...

Superconductor

https://cornerstone.lib.mnsu.edu/cgi/viewcontent.cgi?article=1345&context=etds


"Figure 4: Diagram of the Bragg Law showing the relationship between the diffraction
angle θ and the distance between crystal planes dhkl."

[magnO]

We need to consider how a hollow sphere would be made and magnetized

The spheres are magnetized like in the drawing.

[magnO]

I use google chrome it took me forever to have faith in. Just avoided as much as i could

have no specific preferences for web browser. as I mentioned, irrelevant to the question.

All knowledge is relevant.

In reply to Bruce S "All knowledge is relevant", that is like saying all information is relevant. There are people who "know" the Earth is flat, that meme has taken root in their brain, is that "knowledge" relevant? Darwinian evolution works by creating signal in the noise, in valuing _some_ information, genes, or memes i.e. knowledge, not all information. That is not an insult to JW either, I trust, or assume, JW is a confident person like anyone else, not sure why a reply in a forum would hurt a person, that is like a commercial advertisement hurting a person, like, who cares. I also see the interest in where I found the reference to this forum, had I remembered I would have shared, it was not ill intent, just specifically the browser history is not recorded in guest mode, and like anyone else I do not have a built-in browser history in my brain, it prioritizes other things.

The question I asked is quite simple. The answers I have gotten are divided on "poles are reverse on inside of sphere, alternative 1" and "oh that is just like a standard electric motor, alternative 2", I am interested in which of those is true. It is not in my self-interest to insult anyone, or be impolite, I am merely interested in scientific consensus around which of the orientations the magnets prefer.

[JW]

Hi magnO,

It works both ways, he is there for us both

[MagnetJuice]

magnO, do you have a magnet as in your picture or know for a fact that a magnet like that exists?

If you do, tell us where to verify the existence of this magnet.

If you cannot verify the existence of this magnet, then it would be unreasonable to expect “consensus” on a hypothetical question.

My post above was an attempt to find out if a magnet like the one in your picture was possible in real life. If it can be established that a magnet like that is possible, then there has to be an answer to your question. A physicist who specializes in electromagnetism will have the answer for you.

There could be someone on this forum that have that kind of knowledge, but like I said before it has to be a REAL magnet, not an imagined one.

Ed

[magnO]

magnO, do you have a magnet as in your picture or know for a fact that a magnet like that exists?

If you do, tell us where to verify the existence of this magnet.

It's just a spherical magnet, Google "spherical magnet". Two of those, concentric, one inside the other.

[magnO]

All knowledge is relevant.

Also, re: all knowledge is relevant, what I said was specifically that that piece of knowledge, a link to a forum page, was not relevant _to the question_, not that it lacked value or relevance in general. My previous reply on that is in that sense unnecessary, yes, I can agree with that "all knowledge has relevance" in some way shape or form, but all knowledge is not relevant to all other knowledge specifically.

[magnO]

It works both ways, he is there for us both

and, re: works both ways, the idea that moderation is perfectly neutral and unbiased, tell the story of santa claus as well or, to paraphrase, my response to that idea... takes a shot of Jack Daniel's Tennessee Whiskey and sprays it out my nose

[MagnetJuice]

My Google search for "spherical magnet" produced 19,600 hits. I found some discussion in a Physics Forum. The consensus is that a magnet as your picture it is not possible.

Good luck with your search.

And magnO, here is some unsolicited advice for you. Be careful when speaking your mind just because what you say is truthful, honest and correct. Especially when dealing with Moderators in a forum.

My neighbor lady is a big, fat ugly woman. That is an undeniable fact that anyone that sees her can agree on. But I would not knock on her door and when she opens her door I tell her; “hi, you are a big fat ugly woman”. I could do that if I wanted a broken jaw. 

Ed

[JW]

Ya think this topic is a lightning rod, lock this topic

All in favor say I

[Bruce S]

Relevant to the OP's question.
Are the Sphere's solid or hollow?

I've re-read the posts and cannot find the reference to whether they are solid or hollow.

A Sphere can be either.
One would believe that in order to have a sphere inside another then both could be hollow.
However, the outer one would need to be hollow; while the inner could be either.

A spherical mag still has poles, they do not cancel each other out, similar to sticking two horseshoe mags together.
IF we were to believe the inner mag was solid then again it would merely find the outer mag's opposite poles on the inside and stick there.
IF we have the inner mag as hollow, same thing, it's merely going to find outer mag's opposite poles and stick there.

Magnets follow a completed path , this can be seen using iron shavings .

All of this is on the basis that someone isn't trying to float a magnet inside another. Even then at perfect balance, the inner one will orient itself towards opposite poles (still using opposites attract ).

Bruce S 

[magnO]

My Google search for "spherical magnet" produced 19,600 hits. The consensus is that a magnet as your picture it is not possible.

nonsense. here is a spherical magnet like in the example, very common.

magnet4sale (dot com (slash) sphere-neodymium-magnets-dia-0-5-n42-ndfeb-rare-earth-magnets



also exists dipoles with north outside/south inside, but that is not what the question is about.

[magnO]

also the Earth... spherical magnets with dipole like in the question, very common.

[MagnetJuice]

I have spherical magnets of many sizes.

Read my answer again, it says:

"The consensus is that a magnet as your picture it is not possible"

Like I said before, If you can find a REAL, spherical HOLLOW magnet, let us know.

[magnO]

There is nothing special about a hollow magnetic sphere. Consider a block of magnetic material. You could machine it into a sphere and then hollow it out. Solid ball magnets more common on market, but hollow ball magnets with magnetic field as in the example exist, of course.

[JW]

I am not planning to build anything.

There you have it, we actually build things here

[magnO]

I am not planning to build anything.

There you have it, we actually build things here

Yes that is why I was explicit in my response, that I asked because I came across this forum. Total transparency. I am interested in whether two concentric hollow ball magnets would prefer orientation 1 or 2 in the example below, and a forum of people passionate about electricity and magnetism seemed like a possible place to get an answer, so, I asked, and, have been transparent about the intent.