Yeah, that's right, I like magnets. You got a problem with that?

This post may not appeal to everyone. I feel a particular fondness for magnets, but I fear that some may find it boring if they don't share my interest in this subject. This is one of those posts that I'm writing mostly for myself.  

I started playing with magnets when I was a kid, dragging a horseshoe magnet on a string along what we called the Junky Road, to pick up magnetic sand, which years of trucking iron ore from a Castile Location Mine (in Wakefield, Michigan) had deposited along its route through the woods opposite our house. I also acquired an Erector Set one Christmas with a dry cell battery and would wind copper wire around a 10 penny nail in order to make my own electro-magnet crane.  I moved a lot of paper clips from point A to point B back in those days.

But the years pass, one grows, a living must be made, and magnets were put on the back burner while I was busy with other matters.   

After I retired, I once again began 'playing' with magnets, but they were a new generation of magnets by then. Impressively more powerful than anything I had experienced or even imagined as a kid. These were neodymium magnets and had been developed during the '80's.  

A quick comparison for you.  Magnetic field strength is measured in gauss.  The earth's magnetic field is about .35 to .60 gauss, (Notice, less than one gauss.) depending on where you are measuring it on earth.  A refrigerator magnet has 50 to 100 gauss.  My childhood horseshoe magnet might have been around 300 gauss.  I now have mainly N45 grade neodymium magnets and their gauss reading is pushing 7,000.  Larger magnets of the N52 class, the most powerful currently made, can reach 14,800 gauss. 10,000 gauss equal 1 Tesla. You must agree there is no comparison between magnets then and now.   

The first new magnets I bought were nicknamed Buckyballs.**  They're silver colored (coated in nickel) and 5 mm in diameter. I can't put the individual spheres any closer to the string of them you see on the counter because even at that distance, I can see them 'quivering' in their need to join the string.  

I wrote in a post that I published a couple of months ago, that moving into our modest-sized apartment here at Waitakere Gardens Retirement Village, in some ways, felt to me like returning to the Hunt Hall dormitory where I lived for a time while attending Northern Michigan University, more than 50 years ago.  But obviously, here we have many improvements.    

One of the first things I did to decorate my room back in 1969 was to display this poster, called Relativity, by Escher  

In keeping with the theme shown in the poster, of a multi-dimensioned world, I thought I'd try to add the same flavor to our present day apartment using some magnets. The result is below.

Why should a  vase always have to be displayed on top of a shelf? 

As I said, just playing.  And let me address all you younger folks at this point.  I'm presently 72.  You need to know that you'll never be too old to play.  And if you're old, like me, and not playing in some way, shape or form, you ought to be.  Get with it.  

The actual magnets I so enjoy are not the whole story however. They are like the physical manifestations that allow us to interact with the fundamental structure and properties, and particles of the universe. The molecules, atoms, electrons and the basic forces of nature that scientists still don't fully understand. 

When I began playing with buckyballs and other magnets, I also began studying about what makes them work.  I learned first that the magnetic fields they generate are caused by unpaired electrons in the orbits of the atoms that form them.  That sounded simple enough. But since then, I have learned that that is the very tip of an enormous iceberg.  

Many years ago, I gave Jeanne the teddy bear you see here for Valentine's Day. It has a LOVE tattoo on its arm.  It is holding a string of buckyballs leading up to a couple of ostrich egg balloons, held in place by magnets, of course.  

Another thing I learned when I started studying, was that electricity and magnetism are two sides of the same coin. (My interpretation)  A changing electrical field creates a magnetic field, and a changing magnetic field creates an electrical field. I have now also studied about dipole moments, magnetic domains, magnetic susceptibility, and saturation. I've studied Lenz' Law, and Faraday's, I know what the Curie Point is and what the Neel Temperature is. I know that there are different types of ferromagnetic materials and that there are also paramagnetic, diamagnetic, and antiferromagnetic materials, and I learned about the newly discovered altermagnetism.  I've read about how crystalline structure affects magnetism. (I like this particularly.)

And I've barely started. I learned that to really understand what is going on inside the toys I stick to walls and each other, I would need to study quantum mechanics and I'd need to become proficient in using equations at a level of math that is over my head.  

But basically, I have learned that I enjoy learning about the physics of magnets every bit as much as I enjoy playing with them.    

Inside the container, I have connected three of the same size of magnets which you see suspended above it.  That is a 3 mm brass rod (nonmagnetic) and each magnet has a 4mm hole through it. The floating magnets have their like poles facing and so repel one another and seem to levitate.  The buckyballs, cubes, coin and washer are there simply to add interest to my 'sculpture.' 

Remember how I compared my university dorm room to our present apartment?  Well, there is yet another similarity between these times of my life.  I'm taking a university physics course again, in a way.   

I discovered this series (30+ ) of 801, 802 Physics lectures, given at MIT some years ago. The professor is Walter Lewin.  This is the link to the series and his first lecture. He won't get into his magnetism lectures for some time, but I very much enjoy his style, and demonstrations, and I am picking up bits and pieces of physics during each lecture. (I even take notes.)   

https://www.youtube.com/watch?v=X9c0MRooBzQ

It's wonderful.  All the pleasures of learning about an interesting subject whenever I want to and none of the worry about homework or exams.  I intend to watch the entire series. 

Here, I have a short string of buckyballs standing on the base of a glass,  being held in place by the field from the neodymium sphere magnet above it. It's interesting to note that if I added one more buckyball, the string would jump up to the sphere, and if I removed one, the string would collapse.  We're right at equilibrium. 

The  big sphere is the perfect shape for this demonstration. Its magnetic field lines curve together very close to the bottom point on its surface. The exact center would be the south pole.  If I used a flat-ended magnet instead to attract the Buckyballs, the lines of force around the edges would pull the string to one side or the other.  I don't think it would support the string as well. Furthermore, the field lines in the Buckyballs also leave the top of the uppermost ball very near the north pole, which is at a point in the very center. The south pole above and the north pole below line up very closely, which optimizes the support of the string of Buckyballs.  

If you're at all interested, I also have found videos made the Khan Institute which also explain some of the matter that Lewin discusses, but from a slightly difference angle.  Here is one that I just watched. 

https://www.youtube.com/watch?v=sEGLcpmIIBY

This set up is interesting too.  Note first the strength of the buckyballs.  I have two coins between them and yet the sting holds together.  The large size of the magnetic field of the cylinder magnet can be seen due to the reaction of the string. and remember, that field extends 360 degrees around that cylinder.  And there is another equally powerful field extending through and below the shelf as well. 

This is another demonstration of like poles repelling each other.  And just think, neodymium magnets are long-lived.  They lose only about 5% of their strength every 100 years.  

Here is a new stack I recently bought. Again, they have a 4 mm hole through the centers of each.  The manufacturer places plastic washers between each magnet to make it easier to separate them. 

Below is what I made from some of them.  I used another 3mm brass rod and the electrical tape on the ends keeps them from jumping off the ends. Each magnet was placed so the like poles face one another.  Each is trying hard to repel it's neighbor(s). They're extremely single-minded about that.  (Think of them as a neighborhood of alternating Green Bay Packer and Chicago Bears fans.)

 

Finally, here we have Jeanne compressing the magnets. I didn't measure the force she needed to move them as close together as she has, but it is already significant and gets even harder as they come closer together. BTW, each one of those magnets, if it were attached to a clean sheet of steel, would require about 23 pounds of force to pull it straight off.    

Well, that's pretty much it for this week.  I haven't told you about hard and soft ferromagnets or the Bohr magneton or the degree to which magnetic fields can be redirected.  (Did I just hear a sigh of relief?) 

I have also been hearing about iron nitride (Fe16N2) magnets. They are still being researched and developed but could turn out to be even more powerful than neodymium (Nd2Fe14B) magnets, and much, much cheaper to make.  The element neodymium is expensive to mine and the sintering process they use to make the magnets is complicated.  I'll be watching to see what develops.   

I said at the beginning of this post that I might bore some of you who don't share my interests in magnets.  I think we've all shared some experiences with them, but most of you out there also have more going on in your busy lives than I do.  If you've made it all the way through this post, good for you.  I appreciate being able to share and I had fun writing it.   

One word of warning. These neodymium magnets I've been talking about are surprisingly strong. I think the big ones are actually somewhat scary.  I use a pair of gloves when handling anything stronger than the buckyballs.  And you need to keep even them, especially them, away from small children. There have been deaths caused by babies ingesting them.  

Back in Michigan I had purchased a 2 inch round magnet with a 1/4 inch hole through the center. It was 1 inch thick. It had a holding power of 220 lbs. against steel. I had many others that were smaller but proportionally as strong. If two magnets with such power come together unrestricted, and your hand or finger were in the way, you would suffer badly.  There are videos on You tube showing the correct way to join or separate such magnets.  If you ever intend to buy any, you Must watch these videos first.  Absolute necessity.

And they reach out and grab knives, nails and other sharp objects from surprising distances. Remember the picture I showed you above that demonstrated the size of the magnetic field that was repelling that hanging string of coins and buckyballs? That was from a magnet with only 23 pounds of holding power.  The magnetic fields are proportional in size to the power.  Get those gloves and be careful!  I like snug fitting rubber coated ones but I've seen leather gloves used in some of the videos showing really massive magnets. An N52 magnet, six inches in diameter and two inches thick would have over a ton of holding power. 

Finally, be aware that magnets can affect anything electronic, including phones, computers, heart pacemakers and even credit cards. Don't carry magnets in your pocket next to your wallet.   

Okay, So what do you think? Am I nuts for liking magnets or not? 

According to the guy that does the Science Asylum video's on You Tube, it's okay to be a little crazy. I rest my case.    -djf 

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The reason for the name, Buckyballs, is interesting.  Let me tell you about it very briefly.    

There was an American architect and futurist named Richard Buckminster Fuller. He is most well known for his geodesic dome structures.  

'Buckminsterfullerene' is composed of 60 carbon atoms, arranged in such a way that it looks like a sub-microscopic soccer ball. It does exist in nature (in soot) in very small quantities, but in the 1970's, it was generated in a lab for the first time.  Apparently, the scientists wanted to honor Buckminster Fuller and his geodesic domes and so named this material after him. The tiny structures did look something like his domes after all. It was at this time that they also coined the nickname, Buckyballs. 

When these little neodymium magnets were first being marketed as a product, a catchy name was important to generate sales.  You can see from this cylinder that I made, that they can resemble a geodesic sort of pattern.  The marketers borrowed the name Buckyballs.  

I suppose I could try to make a geodesic dome out the them, but I think that would take a lot of work. This structure is easier to make.  I simply formed a long string of spheres and wound one end into a circle.  Then, I continued laying the rest of the string over the previous layer and each magnet snaped into place next to the last.  Once you have the string, you can build this in a few seconds. It's beautiful, don't you think?

-just one more picture... 

This is one of the 'magnet people' that my grandsons and I used to play with.  Fond memories for this old grandpa. (They're 17 and 15 now)  

There is another more powerful magnet under the table supporting the 'person.'  Moving the magnet under the table causes the people to 'walk' with a somewhat jerky gait.