| Author | Message | ||||||||||||||||||||
     Raymond Liu |
Dear Mr. Field, I'm having trouble building this expirement. The magnets are so strong that when they snap together they crack and sparks come out. How do you even get the supermagnets apart? And I also made the graghte really thin and it won't float above the magnets. Is it because I placed the supermagnets in the wrong order? Please help me. Sincerily, Raymond Liu | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The pyrolytic graphite will probably float fine, even with cracks in the magnets, once you get the magnets oriented properly. They must be oriented with opposite poles next to one another, such as
Once they are in this position, the graphite will float if it is thin enough. | ||||||||||||||||||||
| Raymond Liu |
But how can I get them in that position if they repell? It is hard and even my dad can't do it. If you use a sheet of metal to stick it on there, it is really hard and the magnets move and just stick together. | ||||||||||||||||||||
| Raymond Liu |
You see, I didn't use a knife to make it thinner, I used a sharpening stone to sand it down until it was very,very thin. My dad siad that it was immpossible to cut it with a knife. I tried your advice and it still didn't work. I really want to do this for the science fair. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
It is not hard to arrange the magnets properly. If you have a compass, use it to find the north pole of one of the magnets. Place that magnet north side up on a piece of metal, so it stays in place. Use the compass again on the next magnet, to place it north side down right next to the first. The magnets will not repel, they will stick together, even without being placed on a piece of steel. Place the third magnet north side down on the metal, touching the first magnet. Place the remaining magnet north side up in the remaining corner of the square of magnets. The Pyrolytic Graphite cleaves easily with a sharp knife or razor blade placed against the thin edge. It is also fairly easy to cut using a sharp knife against the flat face, since this stuff is a pure crystal of the same stuff a pencil lead is made of, and is thus fairly soft. | ||||||||||||||||||||
| Raymond Liu |
I finnally got it to work! Thanks a lot!!!!!!! | ||||||||||||||||||||
| Jim Bradley |
I found a convenient way to find the north seeking pole of the 12 mm cubic magnets. I floated the bottom half of a plastic container for 3M electrical tape in a sink of water. I placed the magnets one at a time in the center of the container. If the poles are not vertical, there is a strong orienting force that will cause one side of the magnet to face north. I marked the north seeking side with a felt tip pen. I tested whether the pole is vertical by rotating the top (horizontal) surface 90 degrees to become a vertical surface. The difference is quite clear. Do not do this in a sink made of iron. The magnet may jump to the side wall or bottom. Also any permanent magnetism in sink may confuse the magnetic north direction. I had a convenient Corian sink to use. If I needed to find the N pole of the disk magnets, I would use a little tape or putty to stick the edge of the disk to the bottom of the floating container. One of the potential problems with using a compass to find the north poles is that it is easy to accidently reverse the polarity of the needle if the strong magnet is brought too close when the needle cannot rotate. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
Excellent advice. I have found that holding a magnet loosly in each hand, and then bringing them together (with the hands preventing them from jumping together and shattering), that the two magnets will prefer to arrange themselves with opposite poles towards each other. Since it doesn't matter whether you start with a north pole or a south pole (all we need is to alternate poles), you can then stack the magnets together pole-to-pole:
Now you know that all of the magnets are either north pole up, or south pole up. From here it is easy to arrange them to alternate in the square arrangement. | ||||||||||||||||||||
| elvin roman |
hi, i bought the PG and im having trouble making it float... i cut the PG in three slices and then cut it in half.. and when i put it in top of the magnets it doesnt float.. im not using the square magnets.. but i have some that are pretty strong..they sheets are really thin.. but i dont know whats wrong? im doing a presentation thurs so it will be very nice if i got it to work by then! att elvin | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
You say you are using your own magnets. I have no idea how powerful they are. Our 12 millimeter cubes are the strongest that can be made with current technology -- 48 MegaGaussOersteds. Most of the NdFeB magnets on the market or available at surplus houses are about 30 to 35 MGOe. You should also make sure that your magnets are oriented with alternating poles, as described in the text: N S S N | ||||||||||||||||||||
| W Giles |
Assembling 9 piece magnet levitation What is the pattern for arranging the 9 piece magnet set? I am not sure I understand how to do it from the 4 piece instructions. Thanks. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
It is the same idea -- the poles alternate:
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| W Giles |
In order to explain why the graphite levitates, I want to make a drawing of the magnetic fields. What is their shape? Then I want to compare it to the shape of "regular" fields that makes levitating magnets unstable. Thanks. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The field lines arc from north poles to south poles. The dimple between the poles is where the graphite rests. The humps of the fields are what prevent the graphite from slipping off. A single magnet has field lines going from the north pole to the south pole. If you try to levitate the graphite on a single north pole, the force slopes from the center outwards, like a hill, and the graphite falls off. With four hills, the graphite can rest between them, as a book resting between four balls. | ||||||||||||||||||||
| W Giles |
Thank you! Just to make sure I understand what you say, I would draw 4 humps, with lines going from each N corner to the adjacent S squares. It seems like each hump would be at the center of 4 squares, with the center of each hump on a corner of the center N magnet. Is that right? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The magnetic field is strongest at the centers of the poles. It doesn't matter whether the pole is north or south. The graphite will try to stay away from the centers of the poles. That is why the four magnet version has the graphite with the corners in between the poles. The nine magnet version has the corners aligned towards the farthest magnets, since they are farther away. Imagine hemispheres over each pole. That will give you a reasonable approximation of what the field strengths are. | ||||||||||||||||||||
| W Giles |
Thanks for your help! The project was a hit. We found arranging the magnets was quite easy using the technique suggested earlier of holding them in your hands and moving them slowly together. The magnets were indeed extremely strong, and we did crack one when they slammed together even with the earlier warning to be careful. To explain the physics, we made a model using clay to show the hemsipherical filed strenght at the dipoles rather than drawing them. This message board was great! | ||||||||||||||||||||
| kevin mc |
i was wondering dont you just set the graphite on the magnet and it will hover | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
No. If you place the PG on a magnet, the magnet will repel it, and it will be pushed off the magnet. It is like trying to balance a postcard on a stream of air. When there are four magnets with alternating poles, there are four centers of force pushing on the graphite, and it tries to escape by moving away from all of them, towards the center. | ||||||||||||||||||||
| Greg Nold |
There is another way to do this experiment, and the results are identical. I went to my local Sears Hardware store and purchased a set of carbon motor brushes, since I know that carbon is also diamagnetic. I clamped a brush in the rubber 'soft jaws' of my vice using just enough pressure to hold it still without crushing it. I took a hack saw blade and cut the thinnest slice of carbon I could without cracking it. When finished, I sanded the slice even thinner using sand paper, being careful to keep the thickness uniform over the length of the carbon slice. (Be advised -- sand the carbon over newspaper since it will make a black mess on the floor and on your hands!) I was able to end up with a perfectly rectangular slice of carbon that was slightly thinner than a standard credit card. When I placed this thin slice over the properly arranged cube magnets, the effect was immediate. I put the set up in my display case a month ago, and carbon slice has been levitated there ever since.... perfect stability! | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
Excellent! I think you will find that the pyrolytic graphite is not only much easier to work with, but will levitate about three times higher. The graphite crystals in the PG are all aligned perfectly. Those in carbon brushes are small, and aligned randomly. Since the diamagnetic effect is much more pronounced perpendicular to the crystal faces, and the PG is one big crystal, you get better results. | ||||||||||||||||||||
| Greg Nold |
Looking at the photos, it looks like the pyrolytic graphite does indeed float a bit higher than my slice of carbon. My slice hovers about its own thickness above the magnets, and the graphite seems to be about 3 times higher, just as you said. Still a cool effect though, and easily seen! I'm involved with another NdFeB magnet project now, but when I'm finished I'll purchase some of your pyrolytic graphite just to maximize the effect. Nice web page -- I commend your efforts. There needs to be more education in science, and your site definitely makes it interesting and fun. Greg | ||||||||||||||||||||
| Alex |
Is there a difference in the diamagnetism of PG and carbon graphite? There cant be much, because i managed to get a magnet in mid-air. Thanks alot, Alex | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
Pyrolytic graphite is about 3 times better than either bismuth or regular graphite. Regular graphite is not aligned -- the crystals are jumbled up randomly. Graphite is several times more diamagnetic perpendicular to the plane of the crystal sheets than parallel to it. Randomly oriented graphite does not have enough of the perpendicularly oriented crystals to make it as good as bismuth. The real test comes when you try to levitate ordinary graphite above the magnets. It is much more difficult than with pyrolytic graphite, and usually requires a more elaborate magnet arrangement that is less elegant (small bits of graphite between the poles of two attracting magnets held slightly apart). Getting a magnet to levitate using diamagnetism for stabilization is pretty easy. It can even be done using a person's fingers instead of bismuth or graphite, if the lifting magnet is strong enough. But levitating something other than a magnet is a little harder, and PG works best. | ||||||||||||||||||||
| Alex |
Is there any place other than yourself to buy PG? Y'know like walk in, find, buy, leave? And in the Bronx region...? Thanks again, Alex. P.S. I'm 13! | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
No, this is not the kind of thing you'd find in your local hardware store or drug store. That's why we offer it on the site. Another supplier is SPI: here is their web site. They want $70.56 for a 10mm by 10mm by 1mm piece. It's really nice stuff -- but it is over 40 times more expensive than what we carry, and it doesn't levitate any better. It's used for scanning tunnelling microscopes. | ||||||||||||||||||||
| Merle Ishtar |
Dear Mr. Field, I was just wondering if you could tell me what magnetic levitation is? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
It is lifting something up against gravity, using magnetic fields. In the context used on this web page, it is further constrained to mean that the levitation is stabilized by diamagnetism, instead of by some other force, such as touching a wooden dowel, or being held in place with a string. | ||||||||||||||||||||
| Merle Ishtar |
Thank you Mr. Field! | ||||||||||||||||||||
| Mihitomi Higurashi |
Dear Mr.Field, I am doing some research on Magnetic Levitation and I need to know some future uses of it.Could you please help me? Thank You! | ||||||||||||||||||||
| Matthew |
Mr. Field, Hi, I've surfed your site and its pritty cool. I got a levetation kit and some other kits and I was wondering what other uses there is for polyatric graphite? I have some left over and no more magnets to levetate it on. (Maybe levetating multiple peaces one over eachother occording to their size?) | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The PG won't repel PG. Diamagnetic materials repel magnets, not each other. However, you can build the first type of levitator, where the magnet is levitating, stabilized by two plates of diamagnetic material. Just because I used bismuth in the first one, doesn't mean you can't use a better diamagnetic material, like PG. The magnet floats higher with PG than with bismuth. | ||||||||||||||||||||
| Matthew |
I dont mean levitating PG with PG I mean making one float over the others on a magnet becouse thicker ones dont float as high and the thiner ones float higher. PG ___________ ========== |||||| |||||| Magnets There is two peaces of PG over the magnets, the thicker one floating lower (heavier) | ||||||||||||||||||||
| Matthew |
PG is carbon I wonder if I could use it in the H-Bomb project...? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
Try the two-piece levitation, and let us know if it works. Is there room under the thin one to float a thicker one? Will the thick one shield the thin one from the magnetic field? Let us know! And yes, the PG will work fine in the H-bomb project. So will a bunch of pencil leads. But the carbon rods were free... | ||||||||||||||||||||
| Matthew |
Hmmm.... I took a thinner one and put it on top, I took a thicker one and tryed the bottom.... I tryed puting the thinner one on top of the thicker one.... they all lay on top of eachother, this could be either becouse the PG blocks magnetic waves or it has a extremly light attraction to itself or according to the inverse square law the magnetic field dropps off alot at a certain point so all PG floats around the same spot.... | ||||||||||||||||||||
| Joey |
Hi, Could you tell me some future uses of maglev? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
I think your teacher wants you to be creative here. No one has a crystal ball. What do you think maglev might be useful for? Suppose really strong magnets become commonplace. Such a magnet can float drops of water, so they don't touch any container. Perhaps there are some kinds of chemical analysis or synthesis that would benefit from having no container. Perhaps growing crystals for X-ray diffraction studies. Maybe some of the experiments they currently do in space microgravity could be done more easily or cheaply using diamagnetism instead. See what other ideas you can think of. | ||||||||||||||||||||
| nkinnan |
You said that strong magnets can "float drops of water". Could you please explain that a bit more. Does that mean water is diamagnetic? It occurs to me that seeing water hover in mid air would be even more entertaining than watching PG do the same... | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
Water is diamagnetic. But since it is so much weaker than bismuth or graphite, it takes a very expensive electromagnet to levitate it. You can see pictures of the levitating frog (frogs are mostly water) and drops of water levitating in such a magnet. But that magnet takes amounts of electricity and cooling water that would supply a small town. | ||||||||||||||||||||
| nkinnan |
I can see from the diagram the the turns in this magnet are at a very small ratio to the current being pumped through them. Perhaps a similar effect could be obtained with many thousands, perhaps 10,000 turns of wire carrying instead of 50 amps, say 1 amp. Conservation of energy would seem to indicate that if using 1 amp for example, a higher voltage would be nessicary to achieve the same field density, or does the number of turns change that? Is this something obtainable by a hobbyist or is there a flaw in my logic? I can think of nothing more interesting that creating an "anti-gravity" field in my spare time. Would this be an achievable goal? In fact, with some rubber tubing, and a sufficient supply of mercury and liquid nitrogen, one could create a superconducting electromagnet (mercury becomes superconducting when reduced to very low tempratures) eliminating the electricity-to-heat conversion factor to 0 and greatly reducing the amount of power required. Being a superconductor, coiled into an electromagnet, the only energy loss through the system would be by induction in other nearby conducting objects, and the energy loss through the diamagnetic reaction with whatever is being suspended, thus I suppose that would depend on its weight. It seems to me it would be much less costly to run, but more difficult to build. What do you think? Achievable in either form? This intrigues me greatly. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The Bitter Solenoid mentioned in the link uses 20,000 amps, not 50. It has two coils, but for this discussion, let's pretend there is just one, with 214 turns. We thus have 4,280,000 ampere-turns around a 32 millimeter core. If your goal is 1 amp, then you will need to wind 4,280,000 turns of wire in the same volume as the Bitter Solenoid (if it is larger, you get less magnetic force). If the windings are on top of one another, the effect is a little bit weaker than if the windings are all in the first layer, so let's say 5 million turns will do. The wire has to carry 1 amp, so it can't be very thin. With 5 million turns of wire thick enough to carry 1 ampere, the size of the coil will get bigger than the Bitter Solenoid, so we will have to increase the number of turns to compensate for the outer layers being too far away from the core. Suppose we use 20 gauge wire (half a millimeter thick). We will wind the first layer 10 centimeters high, using 20 turns. There will thus be 250,000 layers, 125 meters thick, for a diameter of 250 meters. The average turn will be made of wire that is 400 meters long. Multiply by 5 million turns and we get 2 million kilometers of wire. The resistance of 20 gauge copper wire is 33.2 ohms per kilometer. The coil thus has 66.4 megohms of resistance. From Ohm's Law, we know that the voltage required to run 1 amp through 66.4 megohms is 66.4 million volts. Now we have a problem, because we have been assuming a thin enamel insulation on our magnet wire, but now we need insulation thick enough to handle 66.4 million volts. Our coil was already over an acre, and now we need to multiply that by about 50 times. The outer coils are kilometers away from the center, and probably don't contribute much to the magnetic field at this point. And we still need 66.4 megawatts of electricity to power this 50 acre device. So let's start over with superconductors. Mercury is not a superconductor at liquid nitrogen temperatures. We will need liquid helium. A better superconductor is niobium. But the problem with superconductors is that while they have no resistance, they still become normal conductors if they are placed in a magnetic field that exceeds some critical value. For the best superconductors at 1.8 Kelvin, this critical value is about 2000 Gauss, or 0.2 Tesla. The Bitter Solenoid described in the link was 20 Tesla, or 100 times the strength of what can be done with superconductors. The Bitter Solenoid is used because it is the best way we currently know how to make sustained high magnetic fields. For even higher fields, people use explosives to implode high current coils. However, these fields don't last very long, and neither would the frog. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
My friend Dr. John Edighoffer has pointed me to a paper on a 12 Tesla superconducting magnet using Nb3Sn alloy embedded in epoxy. The paper can be found here. It is not clear that the frog would survive the liquid helium any better than it would survive the trinitrotoluene. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The same lab that described their 20 Tesla Bitter Solenoid now has a 33.2 Tesla version, that goes to 60 Tesla when pulsed. | ||||||||||||||||||||
| nkinnan |
Well it appears I lack a great deal of knowledge in this area. I appreciate the time you took to go over all the aspects (problems) of my idea in detail. From my understanding of what you wrote, even with the "perfect" superconductor, the power requirements are staggering. I'm assuming that's because of conservation of energy (to create a magnetic field of x strength requires y electrons moving in a circular motion around and within z distance of the bore)? No way around that. 50 amp breaker? Hah! Then again... What about (given the "pefect" superconductor) just creating a single closed loop, a torus. No need for a coil really. Keep dumping energy into the coil, creating a sort of "magnetic capacitor" as more and more electrons begin to circle around the bore in a closed loop with no energy loss through resistance? Sort of like an inductor except closed. To my knowledge the only energy loss in such a system would be through induction in nearby objects and you could just continue building field strength by dumping more current into the loop indefinetly. An electro-magnetic capacitor... what do you think? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
While the resistance of a superconducting loop may be zero, it takes energy to build the magnetic field around it. So you put in a lot of electricity, and you get the 12 Tesla magnet discussed earlier. Now you close the loop, creating a short circuit. Presumably a safety fuse blows, protecting the power supply from destruction. Or the power is shut off, and the loop closed before the magnetic field can collapse very much. The collapsing field will start the electrons flowing again, sustaining the field. Or maybe you just put a loop of superconductor right next to the superconducting coil, so when you power up the coil, the magnetic field starts the electrons in the loop going, and they continue when the power to the coil is removed. So now you have a big permanent magnet. It is encased in reinforced epoxy to withstand the 10,000 pounds per square inch of pressure that is trying to blow the coil apart. It is constantly cooled with liquid helium to keep it below the critical temperature. The frog still freezes solid when you put it inside the coil. If the coil gets above the critical temperature, it will become a normal conductor with lots of current running through it. This will very quickly heat it up as the magnetic field collapses and dumps its energy into the molten metal and hot plasma. The 10,000 psi pressure will be greatly exceeded, and the laboratory gets bigger all of a sudden, with lots of extra fresh air and sunshine. I haven't calculated the energy density of a 12 Tesla coil, but it would be interesting to see if it even came close to a 20 gallon tank of gasoline. My guess is that we won't be supplating internal combustion engines with electric motors powered by collapsing magnetic fields any time soon. | ||||||||||||||||||||
| nkinnan |
You seem to be accepting yet dismissing my idea at the same time. I seek clarification. >>>>>> Or maybe you just put a loop of superconductor right next to the superconducting coil, so when you power up the coil, the magnetic field starts the electrons in the loop going, and they continue when the power to the coil is removed. <<<<<< Thus you could continue to build field strength indefinetly. Also, i'm assuming a "perfect" superconductor at room temperature which does not decompose into a regular conductor above a certain magnetic threshold. Seems the only problem to overcome is the magnetic force trying to blow the contraption apart. As theoretical physicists like to say: That's an engineering problem. Epoxy, whatever. The cooling is also an "engineering problem" if you don't have a perfect superconductor and the loop requires cooling to make it superconductive. I could imagine the torus encased in some sort of high strength material with an outer jacket contining any cooling liquid required while still leaving the bore exposed. A donut within a donut. Seems to me if you keep charging the closed superconductive torus loop with your seperate "charge coil" you could achieve any strength magnet desired, by slowly ramping up the current you are inducting into the loop. A hundred tesla, a thousand tesla, or more assuming the (lets again assume epoxy) isn't strained past its threshold for keeping the loop from exploding. The charge could similarly be drained from the loop through induction should you wish to reclaim the energy which you have stored in it. Theoritical applications include experiements with high-strength magnetic fields (previously unachievable), power storage for later reclamation, weapons use - break the coil and let the field collapse for an EMP bomb, etc. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The electrons in the superconductor are being forced to the outside of the coil by the magnetic field. This is what creates the force trying to blow the coil apart. However, it also affects the current carrying ability of the coil itself. The electrons are pushed to the outside edge of the conductor. As the field increases, the force pushing the electrons into the outer edges increases. The area where the electrons reside gets smaller and smaller. Eventually, there is no more room for them, and the current cannot increase. Worse, the electrons escaping that thin region heat it up, destroying the supercondutivity. You are assuming a perfect superconductor. That is like assuming you have three wishes, or assuming you can travel faster than the speed of light. Any conclusions based on an impossible assumption are suspect, and not generally useful. You can store energy in a magnetic field. However, the energy density is lower than gasoline, and there are expensive obstacles in the way of making a practical device. The people working with superconducting magnets are well aware of the possibilities, and when they find a practical way around the obstacles, we will read about it in Science, Nature, or Physical Review Letters. | ||||||||||||||||||||
| nick |
When Superconductor of type 2 levitates over magnet it uses flux-pinning effect. Does pyrolytic graphite allow any flux pinning? Is there any phenomenon of this kind? Actually, I have one idea and to make it work I would like to have pyrolytic graphite sample that would not allow any kind of flux pinning or magnetic field penetration of any kind. Do you have a picture of molecular structure of pyrolytic graphite and bismuth? please duplicate your answer to my email. Thank you for this great site and great job that you do!!! | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
There is no flux pinning with ordinary diamagnets. When you turn the pyrolytic graphite levitator upside-down the graphite simply slides off. With flux pinning, it would stay suspended underneath. The PG does not prevent all magnetic field penetration. PG is layers of hexagons of carbon. Each carbon in one layer is above the center of the hexagon in the layer below. Bismuth crystals are monoclinic. In bulk, the crystals are randomly oriented. See this page for a picture. | ||||||||||||||||||||
| nick |
thank you for link and explanations!!! as far as I understand PG cannot serve as a magnet shield. It just can float over the magnet. It allows some field penetration. How much penetration it allows (in % from total volume of flux)? Does it depend on the field orientation? I do not need exact numbers - just a general evluation. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
If you want a magnetic shield, use a piece of iron or steel. A diamagnet is like a mirror. The magnet sees its reflection, and the like poles repel. What are you trying to accomplish? We can help you better with more information. | ||||||||||||||||||||
| nick |
I want to build a magnetic bearing and I want to know if PG can serve in this way. I also do not want that magnetic field influence to other metallic parts what is a carrying capacity of PG? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The reason you need to split the PG into thin pieces is because it can't lift the weight of the 0.5 millimeters of PG in the upper half of a 1 millimeter thick piece. We are using the strongest permanent magnets mankind knows how to make, and the most diamagnetic substance known at room temperature. Even so, it just barely works. There are many patents on magnetic bearings. You can find out how to make one by reading some of those patents. Go to the patent office to read them. | ||||||||||||||||||||
| Jerry Ellison |
Tips/Discussion: 1) These little magnets are indeed very strong. I was surprised, the sellers are not lying. They will jump long distances if you let them. For me, this little surprise was pretty cool all by itself. I'm curious as to how big you can get them at reasonable prices? 2) The magnets from the kit are connected in a square, but they are not necessarily with alternating poles from the box like you are supposed to have them. For example, mine came with two magnets aligned n/s next to two s/n so than no poles were face up. It's simple enough to find which direction the poles are aligned, but some people might not think to check since they are already in a square pattern. Also, you don't have to find out which particular pole is which, only that the poles are sticking upright from the surface you lay the magnets on, and that they alternate. When you have them in the right position the effect is noticeable right away on the graphite. 3) Do the owners know if the pyrolitic graphite retains this diamagnetic properties in other states or does it have to be in the solid state that it was created in? Do you have any information on interesting effects from unusual shapes? Are there any studies on using it in experiments with the Casimir Effect? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
1. We can make them in dangerously large sizes. But those are not toys. They are very difficult to handle. They must be shipped in steel containers so they don't attach themselves to the truck, or interfere with compasses. As the demand is low, and the tooling costs can't be amortized over tens of thousands of magnets, the costs are disproportionately high. And did I mention that they are dangerous? 2. Exactly. 3. Graphite is most diamagnetic perpendicular to the orientation of the sheets of carbon hexagons. This is why pyrolytic graphite, which is basically a single crystal, is so much better than randomly oriented graphite, such as that in pencils and bulk graphite. It would be very difficult to make a liquid or a gas out of pyrolytic graphite, and the result would not perform anything like the solid form. Disks of PG allow rotation while levitating. Other shapes are certainly possible, but I am having a hard time thinking of any shape that is particularly interesting other than three: a. The square shape is nice because the levitating object is stable in all three axes (pitch, roll, and yaw). b. The disk is nice because it is stable in pitch and roll, but allows yaw (rotation), allowing it to be used as a bearing for lightweight spinning things, such as paper propellers. c. A narrow rectangle. If you place several of the four-magnet units in a row, the narrow rectangle will slide along the entire length. This can be used as a level, or inclinometer. The Casimir effect is independent of what the material is made of. Glass is probably the cheapest and easiest thing to make optical flats out of, and the Casimir effect needs something extremely flat. But I have no experience with the Casimir effect, and I would be happy to be corrected on any of the statements in this paragraph. | ||||||||||||||||||||
| R.W.T.Cooksey |
I found your site whilst pursuing a train of thought - How to make a (thin) compact compass. My main concern was the support pivot and achieving a level within a very low profile. A-HA - magnetic suspension I cried, then thought about the free rotation and the (bar magnet) indicator. Boo - Hoo. Then reading about the properties of PG on this board, I am wandering that if the PG is disc shaped (smaller than the base magnets array) and the needle is on top of the PG (and smaller), will it work ??? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The needle would get firmly stuck to the extremely powerful magnets a millimeter below it. Consider instead a 1 millimeter long compass needle. Attach it to a 1 millimeter bead of styrofoam. Place it in a 4 millimeter wide clear tube, standing upright, half full of water. The water will form a meniscus in the tube. The compass will center itself in the tube due to gravity causing it to seek the lowest point. The whole thing is no larger that the active element in a spirit level. | ||||||||||||||||||||
| Mark Ford |
I have tried this using Carbon Fibre sheet (STUCK ONTO WOOD SHEETS), I suspended a small powerful disc magnet between two sheets of Carbon fibre with a large magnet suspended above and it worked there is a very small stability band though and the distance from each plate is quite small but you can see through it. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
Normal graphite (randomly oriented crystals) is not as diamagnetic as bismuth. Carbon fiber is even less diamagnetic than that. Pyrolytic graphite is 3 times more diamagnetic that bismuth. The fact that you attained stability with carbon fiber sheets is quite a feat. If you replace them with bismuth or pyrolytic graphite, there will be a much better separation between the diamagnet and the magnet. | ||||||||||||||||||||
| Mark |
Would I be right in assuming that a Diamond could be suspended in the same way? since this is a single crystal of carbon? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
Diamond is a closed shell insulator, like silicon, sodium chloride, and silicon dioxide (quartz). These all have electrons with paired spins, and filled electron bands like a closed shell atom such as helium, neon, argon, etc. These properties make all of these things very weak diamagnets. Here are the relative diamagnetic strengths:
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| Mark |
I have been looking into Bismuth shot (used as 'lead free' gun pellets), it seems that most Bismuth shot is actually Bismuth alloyed with Tin. would there be much difference actual levitation difference between Tin-Bismuth shot and 99.99% Pure Bismuth? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
You are not likely to see any difference. The 2% or so of tin that is added will not make a noticeable difference. | ||||||||||||||||||||
| Mark |
Would Bismuth foil float in the same way as PG ? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
No. Bismuth is much too heavy, and is not as diamagnetic as pyrolytic graphite. | ||||||||||||||||||||
| david crockett |
I bought the nine magnet deal. I got all nine magnets together, three, three & three forming a square. the graphite is so thin you can near bout see thru it. It still will not float. I think I just threw away forty dollars for nothing. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
If you read the messages above, you will find that your problem is that the poles of your magnets need to alternate. In the case of nine magnets, that would be: NSN SNS NSN Check the poles using one of the methods mentioned above. Once you get the orientation right, it will float just fine. | ||||||||||||||||||||
| mark |
David, I found that, a good way to do this without using a compass is to put two single magnets together and then put a small piece of 'PG' (graphite) over the join between the magnets - if the PG starts to float then you have the two magnets correct, if it doesnt you need to change the sides that are touching each other until the PG does start to float when you put it over the join (it will not hover at this stage, just float & repel), repeat for the other magnets then carefully bring the pairs of magnets together in the same way and check for levitation and adjusting accordingly. It really does work! but they have to be correctly orientated in the special arrangment : NSN SNS NSN or SNS NSN SNS You dont need the PG too thin either (if it's too thin it doesnt work well) a millimeter or so thick by 10mm square is a good starting size. | ||||||||||||||||||||
| mike koscal |
I am doing the levatating pyrolytic graphite experiment for my daughter's science fair project. A couple questions we have: 1. Why is the special configuration needed for the 4 magnets as opposed to having all the North or South poles pointing up? 2. If we use 8 magnets and with the 4 magnet configuration but stacked two high, should the graphite float higher? 3. As part of the fair requirments we must try multiple substances. I don't understand why the Bismuth Foil would not expect to float. I thought somewhere it stated it was twice as dense as the graphite and 1/3 a diamagnetic so if the foil was 1/6 the thickness of the graphite wouldn't it levatate? | ||||||||||||||||||||
| Anonymous |
suppose that the ammount of bismuth that is melted and molded [see http://www.fieldlines.com/other/diamag1.html]is doubled and the distence between the two is also doubled should the magnets float higher someone please try this for me and post the results. | ||||||||||||||||||||
| Anonymous |
should the bismuth plates just be doubled in hight and should a bigger magnet be used.[see the above site] it would be helpful if someone tryed this too. By the same Anonymous as above. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
That site got their design from me. You can see the rounded bismuth was poured into a soda can just like my first one was. Doubling the amount of bismuth would not do much at all. The effect falls off rapidly with distance, and most of the lifting is done by the thin layer of bismuth closest to the magnet. To get better distance, you can do three things. 1. Use something more diamagnetic than bismuth, such as the pyrolytic graphite we offer in our catalog. 2. Use a stronger magnet as the lifting magnet on top. 3. Use a floating magnet that has a higher strength to weight ratio. Ours are 48 MegaGaussOersteds. The ones from Radio Shack are 27 MGOe, and barely work at all. The ones you get from disk drives are about 30 MGOe. | ||||||||||||||||||||
| Anonymous |
would you please suggest some sites that are related to this experement? still by the same Anonymous | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
The best sites are by my friends Martin Simon and Andre Geim. You can look them up in Google. Other things to Google are Meredith Lamb, and Pyrolytic Graphite. | ||||||||||||||||||||
| Anonymous |
thanks for responding! still by the same Anonymous | ||||||||||||||||||||
| C Richard |
Is this a possibility?: Diamagnetic levitation to create an electric generator? I'm thinking: Diamagnetic material on bottom (and maybe top with ceramic or electromagnet on top of that) with the rare earth magnet spinning. If windings of copper were placed around the spinning magnet, could the assembly be hooked up to say a very low watt lightbulb; would this work? | ||||||||||||||||||||
| Alessandro |
Hello, I'm doing some experiments... how would an electromagnet made to use it instead of your permanent magnets? Wich magnetic field in Tesla and wich inductance? Thank you in advance and compliments for your web-site! Alessandro | ||||||||||||||||||||
| Z Feirer |
How would one go about creating an electromagnet w/ a strength of 48MGOe? Is it even possible? | ||||||||||||||||||||
| Alessandro |
I have seen on the web that with (very) strong electromagnets they are able to levitate even frogs! I think diamagn strenght of a frog (and the weight) is very less than the phyrolytic graphite you supply, so I think with a strong electromagnet would be possible to do levitation! | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
Indeed. See this page. As for a 48 MGOe electromagnet, this one is even stronger. | ||||||||||||||||||||
| Z Feirer |
I've seen magnets like that before, but I was talking about one you could build at home. I don't need to levitate frog (although that would be really cool), but i hav a couple of ideas tat require electromagnets about the strength of the 12mm cubes you sell. | ||||||||||||||||||||
| Kevin F. Lynch |
Dear Simon, I am a biology teacher that has been teaching low level physics for a number of years I have your Gonzo Gizmos book and am curious about your explanation for rocket travel I thought their would be no "pushing" on the rocket firing chamber and that it was more of a case of rapidly throwing the rocket fuel mass out the firing chamber area and having Newton's third law take over. This would be similar to throwing items of clothing toward the middle of the pond inorder to have the reaction of moving toward the shore as the reaction Is this how it works??? Please respond and clear up this mystery for me by replying via my email Thank You | ||||||||||||||||||||
| Simon Quellen Field (Sfield) |
If you want a private reply, don't use the public forum. ;-) Suppose you plug up the nozzle of the rocket before you light it. The chemical reaction will still take place, and you now have a lot of hot gas under a lot of pressure. Pressure means pushing. Something is indeed pushing on all sides of the chamber. Because the pushing is equal in all directions, the rocket does not go anywhere. Now you unplug the nozzle. Suddenly, there is nothing pushing on the rear wall, since any molecules going that direction find no wall to push against. But there are still molecules pushing equally on all the remaining walls. The rocket doesn't go sideways because the left and right pressures are the same. But the top of the chamber is being pushed upward, and there is nothing pushing downward. The rocket goes up. Newtons 3rd law says that if I push on something, it pushes back with the same force. When you push your shirt towards the center of the pond, it pushes you back towards the shore. You can feel this push on your hands as a pressure. If you pushed on a wall with the same pressure, you would move away from the wall at the same speed. Whether you throw the shirt or push on the wall makes no difference, as long as the pressure you feel against your hand is the same. | ||||||||||||||||||||
| New Magnet Guy Unregistered guest |
Dear Mr. Field, Im very new to the world of magnets and i believe they have greater potential than anyone wil say. I had a few questions that i beieve you could help me out on. First, what kind of magnets are used in the production of electrity? Second which magnets are the strongest at repelling one another? Third, If i was usuing the magnets from question 2 what would be the push force of them? (What is the formula for how much a magnet can push free of resistances) If you could answer these questions that would be great thanx again. New magnet guy | ||||||||||||||||||||
| Simon Quellen Field (sfield) New member Username: sfield Post Number: 10 Registered: 12-2004 |
Any magnet can be used to produce electricity. Commercial power companies use electromagnets. Bicycle generators use permanent magnets. For magnets the same size, neodymium-iron-boron magnets are strongest, and within that type, the numbers range from 20 MegaGaussOersteds to 50 MGOe, usually named N20 to N50. The N50 magnets actually measure out to about 48 MGOe, and that is what we call them, and what we ship. | ||||||||||||||||||||
| New Magnet Guy Unregistered guest |
Maybe you answered my question and i just dont get it but, is there a basic formula to figure the magnet strength and how much weight that can push. Like how much weight could a 20 MegaGaussOesteds magnet push free of lets say air resistance? | ||||||||||||||||||||
| Simon Quellen Field (sfield) New member Username: sfield Post Number: 11 Registered: 12-2004 |
Free of resistance, it could push the entire earth. | ||||||||||||||||||||
| New Magnet Guy Unregistered guest |
WHAT??!!? Crazy... Ok i have anoher question. Are there any type of magnets that dont work until you give them an electric shock or something? Like, as soon as they get shocked they become magnetized? | ||||||||||||||||||||
| Simon Quellen Field (sfield) New member Username: sfield Post Number: 13 Registered: 12-2004 |
A coil of wire will do that. | ||||||||||||||||||||
| Anonymous |
I had my graphite levitated before, but I had the plastic spacers between the magnets. Then I noticed that the photos on your site don't have spacers between the magnets, so I removed them, but in so doing the magnets crashed together (I know...) and a corner smashed off one. Every since I'm unable to recreate the effect. Is it possible that the oriention of the field could have changed in the magnets ? | ||||||||||||||||||||
| Simon Quellen Field (sfield) New member Username: sfield Post Number: 20 Registered: 12-2004 |
Most likely you have simply mis-arranged the magnets. Make sure they are NS SN and they will probably work just fine. | ||||||||||||||||||||
| Anonymous |
Thinking about it, I can't see how it's possible to arrange 4 magnets in any other way than NS SN if they are to form a stable group because poles must alternate to attract eachother. | ||||||||||||||||||||
| Black Magnet Unregistered guest |
Right. Here's my method of alignment: Using strength and care hold two magnets apart from eachother and rotate them so that they repel evenly (a symetrical field). Now you know they are facing NN or SS, so rotate them both 90degrees and then invert one. Now carefully bring them together by pulling them apart as they close in. Repeat with the other pair and then join the two pairs by feeling the field and again pulling them apart as they close in to counter the acceleration you feel. If you get it wrong then you have a circular arrangement where the field forms a closed loop rather than a cusion with a dimple in the centre. | ||||||||||||||||||||
| Simon Quellen Field (sfield) New member Username: sfield Post Number: 23 Registered: 12-2004 |
With respect to the Anonymous post at 3:58: The poles must all be facing up. If you allow the poles to attract one another, then they will be facing sideways. The arrangement with all the poles vertical is not the most stable grouping, and will not happen by random chance. The magnets would rather assume an arrangement where at least one set has poles facing each other. I find it is easiest to arrange the magnets on a steel surface, or on a piece of cardboard on top of a steel surface, so that the magnets do not jump together. | ||||||||||||||||||||
| Anonymous |
hi i got this experiment and i cut the grafit so thin with a scalpel that you can see throue it it must easly be 0.1mm but the stupid thig will NOT flote and i would sllso like 2 know haow 2 arande 9 magnets so if flotes better i have 9 lol if ya can help pleez e maile me at ross123540@yahoo.com | ||||||||||||||||||||
| Simon Quellen Field (sfield) New member Username: sfield Post Number: 83 Registered: 12-2004 |
Have you read this message thread carefully? If it isn't floating, your magnets are not arranged with the poles vertical and alternating. Read the above messages carefully to see how to arrange the magnets properly. I am assuming you bought the magnets and the pyrolytic graphite from our catalog. Weaker magnets will not work. | ||||||||||||||||||||
| Jag Unregistered guest |
Was there ever an answer posted to C Richards question? "Is this a possibility?: Diamagnetic levitation to create an electric generator? I'm thinking: Diamagnetic material on bottom (and maybe top with ceramic or electromagnet on top of that) with the rare earth magnet spinning. If windings of copper were placed around the spinning magnet, could the assembly be hooked up to say a very low watt lightbulb; would this work? " Thanks, By the way Sfied, you're a genius! | ||||||||||||||||||||
| Simon Quellen Field (sfield) New member Username: sfield Post Number: 189 Registered: 12-2004 |
The levitating magnet has the poles vertical. Spinning the magnet would not change where the poles are, so there would be no power generated. If you did spin the poles end over end, the magnet would not levitate. If you spun the coils around the magnet, the drag would tip the magnet, and it would spin end over end, ceasing to levitate. Besides, if you are moving the coils, there is no advantage to having the magnet levitate in the first place. | ||||||||||||||||||||
| Anonymous |
Hi Mr Field, Instead of using PG, bundle of pencil lead works as well? If it does, must I align the leads in a straight line or clumping them together is fine? | ||||||||||||||||||||
| MadScientist Unregistered guest |
Mr Field, First, I would like to say that pound for pound, the PG lev is the most intriguing experiment I've ever done for the money... and for the benefit of the other viewers of the forum, I'd like to add yet another way to find the poles of the magnets... I actually bought 2 sets of the gauss rifle kits and just added on some PG to the order to give the purchase a little more bang for the buck. I noticed after playing with them that the balls eat away a little of the gold plating on the center of the poles of the magnets from striking them after several shots, visibly marking them with a grey dot. Granted, this doesnt tell you the polarity, but If one cant figure out which is which at that point, I would imagine that it couldnt BE explained.  This makes it really easy to find them if you are using the magnets for more than one purpose as I am. On another note, I rounded off one piece of the PG to see how it affected it, and of course found out about the Z stability issue (before reading it above), but in the process noticed that Eddy currents seem to be at play here, as graphite is conductive. I realize that the PG has very little mass, but also has very little surface area, and so air drag cant be playing much of a role. If Eddy currents are the cause, is there a way to minimize its effects so that a very efficient, lightweight bearing could be made (I want to make a miniature version of a much larger electrostatic motor that I built several years ago), and it seems that it could be possible if the 'friction' of the PG bearing is low enough. The basic idea for the entire shaft is to use a PG bearing on the bottom, and a needle at the top with another magnet above it to hold it erect, and to help support the weight of the rotor assembly in general. I picture a hybrid configuration somewhere in between the bismuth and PG projects. Do you think it would be practical to try? I ask first because the original was an extensive project, not anywhere as simple as the standard styrofoam cup/soda can type configuration. It roughly resembles the inside of the average toy DC PM motor. One other thing came to mind... how big would the main bearing need to be in order to be both stable and support the weight of the shaft (just a rough guess)? Oh - one more thing, on the topic of eddy currents - An interesting addition to the site would be the 'drop a strong magnet inside the copper pipe' experiment... Thanks for reading, I know its a bit windy... Steve | ||||||||||||||||||||
| Simon Quellen Field (sfield) Senior Member Username: sfield Post Number: 324 Registered: 12-2004 |
In general, low friction bearings are used when the amount of energy available is very small, or the speed of the rotation is very high. Since neither is the case in your device, you might just use a normal bearing, and apply a little more current. The levitation devices I describe do not use strong forces to hold the material in place. It is easy to push the PG off the magnets, or to blow the floating magnet out from between the bismuth plates with your breath. This means that any device suspended in this way and rotating must be very well balanced, or it will produce sideways forces that overcome the bearing's abilities. The PG levitates because it is light. Adding weight will only work up to a point. The floating magnet works because it has a high magnetic strength to weight ratio. Again, adding weight reduces that ratio. | ||||||||||||||||||||
| MadScientist (madscientist) New member Username: madscientist Post Number: 2 Registered: 4-2005 |
Mr Field, I understand the problem with the bearing issue, and of course, it would only be able to support a minimal amount of weight. The key thing missed here, is that it is VERY fractional (if that term can be coined) horsepower, probably a millionth or two... The current version works solely from electrostatic fields, and there is about a 1 inch gap between the stator and rotor (chosen by materials available originally, not by choice) and it is somewhat more efficient than the design stated on the average web page, but barely. Without going into extreme detail, the original motor is basically a 1 liter bottle as the rotor w/ 3 poles sitting on a steel rod sharpened to a point, inside a 2 liter stator w/ 2 poles. It runs nicely (up to about 1000 RPM, at which point imbalances start to show and it flies apart) on anywhere from 15-30KV @ only uA. The micro version will probably only be about 2 inches tall, and 1.5 inches in diameter, and I'm thinking would not run near as fast because of stability issues in the bearings, as well as shorter dielectric gaps, so the supply voltage would be lower. I'm using aluminum foil for the poles. I would be happy just getting it to spin at all (20-30 rpm?) Ever seen the web sites devoted to fly-powered airplains? It is the same type of thing, trying to get physics to agree with you on a very delicate level. I just want something that can spin at about the rate the average solar-vane does, no real use, other than to know it is spinning completely hovering in mid-air. Dont forget that some of the weight will be held up by the needle. Steve | ||||||||||||||||||||
| MadScientist (madscientist) Intermediate Member Username: madscientist Post Number: 36 Registered: 4-2005 |
What was I thinking? Coined? Forgive me people, brain-farts are a common occurence in my world | ||||||||||||||||||||
| victor Unregistered guest |
Regarding levitation of water - I saw a previous post about the levitation of water, and I just wanted to mention that water has indeed been levitated using NdFeB magnets. Granted the volumes are very small, but it has been achieved. See the article here: http://physicsweb.org/articles/news/8/9/3 I am trying to replicate their experiment on my own, but have been unsuccessful so far. I am currently using 1/8" x 1/4" x 1/2" NdFeB magnets of grade 35MGOe. I arrange them so that their like poles are facing each other, similar to the setup from the article. However I haven't seen any levitation. I am thinking of using graphite powder to see if I can at least get that to levitate, but have had no luck with that either. I am using typical artist's quality graphite powder. My next thought was to use pyrolytic graphite, but due to the size of the device, I am thinking about grinding it into powder. What do you think? I am also thinking of buying higher grade magnets, but I don't know if that would make the difference between levitation or not. | ||||||||||||||||||||
| Simon Quellen Field (sfield) Senior Member Username: sfield Post Number: 360 Registered: 12-2004 |
The magnets in the article are a quarter of a millimeter high. The drops are so small that they would float in air for a long time just on their own, much like the drops in a fog or a cloud. They are small enough to be subject to Brownian motion. The magnet simply traps them. The full article also describes a device using 2 millimeter high magnets, so our tiny magnets may work. They are 50 MegaGaussOersteds, and thus might be better suited than your 35 MGOe magnets. The substrate is steel, and should be easy to come by ;-) The slit is 1 quarter of the height of the magnets (up to 0.4 times the height), so you will want the 2mm magnets to be 0.5 mm apart. They have even levitated microscopic grains of bismuth, so the powdered pyrolytic graphite should work fine. Other graphite may have contaminants that make it magnetic enough to stick to the magnets instead of repel. | ||||||||||||||||||||
| victor yeh (victor) New member Username: victor Post Number: 1 Registered: 5-2005 |
Yeah, I found out the hard way that my graphite was not quite pure. They were sticking to the poles of my magnet. =( I was wondering if you know of any magnets out there that are even higher grade than the 48 MGOe magnets in the catalog. Still, yours are the highest grade of magnets that I've seen so far, so I am going to place an order for your tiny magnets. As for pyrolytic graphite powder, I only saw whole pieces of it for sale, so I will probably grind it up with sandpaper or something. (That won't make the graphite less diamagnetic, right?) I'm not sure if the steel substrate is needed for levitation. I think they used it for electrodes that manipulated the droplet, and probably as something to mount the magnets on. Thanks for the all the input--I really appreciate it. | ||||||||||||||||||||
| Simon Quellen Field (sfield) Senior Member Username: sfield Post Number: 362 Registered: 12-2004 |
Our latest batch of magnets are N50. As the technology improves, we will provide the best available. PG is anisotropic -- the diamagnetism is higher perpendicular to the cleavage plane than parallel to it (all very pure graphite is like that). So the powder will flip to present the lowest energy profile, which will be the lower value for diamagnetism, which is closer to that of bismuth. But it makes up for it by being much lighter. | ||||||||||||||||||||
| AnotherAnonymous Unregistered guest |
Hmm, so from what you say Simon... PG powder would actually be *harder* to levitate than just very pure randomized graphite (like pencil lead), as PG would orient to present a lower energy profile than is possible with RG (unless you could powder it down to molecule size pieces). So... make some powder from non-ferromagnetic pencil lead. A good way to test the weak diamagnetivity of such is to levitate a magnet between PG or bismuth plates, and then poke at it with a various types of pencil leads. Whichever ones repel it the most (without touching) are the most diamagnetic. Some may attract it, avoid those. I got a bunch of 1/4" graphite welding rod, some rods have enough impurity to lift a NIB magnet, others are diamagnetic enough (in slices) to float like PG over NIB magnets, in all 3 orientations, odd! If I have time, I'll try some of the diamagnetic rod in powder form over some NIBs | ||||||||||||||||||||
| victor yeh (victor) New member Username: victor Post Number: 2 Registered: 5-2005 |
I was afraid that would be the answer. In that case, I should probably just buy the graphite rod to make my graphite powder then. It would be a waste to buy PG if its powdered form will not levitate as easily as RG. As for the thickness of the magnets, since they used very thin magnets to create a high magnetic field gradient, do you know how can get some thin magnets like that? I'm guessing that nobody makes magnets that thin due to brittleness, so that means we would have to find a way to do it ourselves. Would it be possible to cut/sand the magnet down and then coat it again to achieve a thin magnet? | ||||||||||||||||||||
| MadScientist (madscientist) Intermediate Member Username: madscientist Post Number: 40 Registered: 4-2005 |
In theory, wouldnt the particles of any powdered form of graphite just orient themselves in such a way that they no longer are repelled by the magnets, and simply give in to the force of gravity? Particularly the PG since it is 'polarized'. As for the levitation in all 3 orientations, one would assume that it is random enough that no matter what direction they are facing, there is always a repulsive force there, given that there is something to support the mis-aligned particles, such as a bonding agent (I would imagine the force produced would be reduced by about a third however, as opposed to PG?) | ||||||||||||||||||||
| Simon Quellen Field (sfield) Senior Member Username: sfield Post Number: 364 Registered: 12-2004 |
PG is not "harder" to levitate than mined graphite. It will generally levitate better, because of its purity. Mined graphite, or worse, graphite that has been powdered and then mixed with clay, as in pencil leads, has impurities that make it heavier and less diamagnetic. In any powedered graphite the particles will align so as to levitate least, but they will still levitate better than any other material. The pyrolytic graphite will work better than anything else you will be able to find at room temperature. | ||||||||||||||||||||
| AnotherAnonymous Unregistered guest |
"So the powder will flip to present the lowest energy profile..." Now, in powder PG that would reduce the diamagetivity to a lower value than that of randomized (pure, not mined) powder, no? Since it is the individual graphite (sheet shape) molecules that are repelled, and if they are randomized, then they can never be all vertically aligned to the magnetic field, and would actually have more levitation than PG. Hypothetical of course since most pure graphite is PG, but if you had pure random graphite powder, it theoretically should levitate better. Imagine a bunch of spheres (say, 10 micron) of graphite, in PG and in random. The PG spheres would tip over, but the randomized ones wouldn't generally. Since the horizontal diamagnetivity of graphite is lower than the vertical, the randomized ones would levitate more, and hence be easier to levitate, no? As for thin magnets, you can get N50s down to 0.5mm here: http://engconcepts.net/List_Of_Disc_Magnets.asp | ||||||||||||||||||||
| Simon Quellen Field (sfield) Senior Member Username: sfield Post Number: 366 Registered: 12-2004 |
No. Any particles small enough for this experiment will be single crystals, and will align to present the lowest energy profile. Impure crystals will weigh more and be less diamagnetic. Note that we are talking about invisibly microscopic dust grains here. You will need a microscope to see them. The pyrolytic graphite powder will still be the best levitator. The half millimeter thick magnets you mention are magnetized the wrong way. They are disks that have their north and south poles on the flat parts of the disk. You want a quarter millimeter thick magnet with the poles at the thinnest part. The disks have the poles at the thickest part. | ||||||||||||||||||||
| AnotherAnonymous Unregistered guest |
victor said: "I am thinking of using graphite powder to see if I can at least get that to levitate, but have had no luck with that either. I am using typical artist's quality graphite powder. My next thought was to use pyrolytic graphite, but due to the size of the device, I am thinking about grinding it into powder. What do you think?". Somehow I doubt he is getting single crystals. Besides, if they are single crystals, they are aligned anyways, and are basically the same as PG. So the only advantage of PG would be purity. And the site has N50 1mm magnet discs .5mm thick. Magnetized through the thickest part that is still only 1mm. There are some 1.5mm x 5mm magnetized through the length too. The webmaster will also sometimes do custom orders if asked nicely. | ||||||||||||||||||||
| jason Unregistered guest |
hello i am doin a science fair for my school and it is all about is it possible to make a mini hover board using magnets? i have gone futher into this but i just cant seem to fine out why this wont work, can you please email me back with some reasons why i cant get a board with a magnet on it to levitate from the magnet on the platform which is on the floor. note that the magnets are both on north pole. thank you. jason sparks. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 482 Registered: 12-2004 |
Read about Earnshaw's Theorem. You can make your hoverboard out of pyrolytic graphite. See this page for more information. | ||||||||||||||||||||
| Charles Van Neste Unregistered guest |
Simon, In regard to what was stated about pyrolytic graphite as a magnetic shield, if it can repel the magnetic field of strong magnets, would this not be a form of shielding? True some field lines will continue to penetrate through, but a good percentage of them would be repelled; similar to strong magnet against a weak magnet. If you had a layer of pyrolytic graphite next to a layer of high permeability/high saturation material I don't see why this would not make a very nice shielding. The high permeability/high saturation material will absorb those field lines that don’t get reflected by pyrolytic graphite. This could be done to reduce the thickness and weight of shielding metal when in close proximity of intense fields. Does this seem correct or is there a flaw here? Thanks, Charles | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 514 Registered: 12-2004 |
Magnetic fields are not like rays of light that can be reflected. A magnetic line of force goes from the north pole to the south pole of a magnet, no matter what is placed nearby. Some materials conduct magnetic fields better than others. A steel object conducts much better than air, so the lines of force go through the steel instead of through the air. The air then has much less of the field going through it than before, since the field is now concentrated in the steel. Diamagnetic materials do not repel the field, the field is simply not conducted through them as easily as through air. So the field lines go around the diamagnetic material to get from north to south, since that is the lower energy path (more lines can fit in the same area). It is somewhat like an island in a river -- the water flows around the island because that takes less energy than going over the island. But the water is going to go past the island -- it is not all reflected back uphill by the island. A piece of steel moves towards the magnet because by doing so more field lines can go through it, lowering the energy of the field. A diamagnetic material moves away from the magnet because that allows more field lines to crowd in closer to the magnet, again, lowering the energy state of the system. Since there is a finite amount of magnetic flux going from north to south, once you conduct all of it through something like steel, there is no more flux to detect outside of the steel. This is why you can put a magnet inside a steel box and not detect the field outside of the box. | ||||||||||||||||||||
| Charles Van Neste Unregistered guest |
Simon, I think I'm starting to understand but not fully. Let me brake this up into groups so its easier for you to correct my erroneous statements. 1.) I realize magnetic flux travel north to south. In ferrite materials when a magnet is present, the electrons, which are unpaired, begin to spin in unison creating a magnetic dipole that is opposite to the field applied. This causes the attractive nature of ferrite metals to magnetic fields. This is also what causes a permanent magnet to stay magnetized after the source has been brought away (the electrons continue to spin in unison.) 2.) As I understand it, diamagnetic materials do the same however their electrons set up dipoles of the SAME pole as the applied field (some what like eddy currents at the atomic level.) Causing a repulsion effect which is why the pyrolytic graphite will "roll" off either of the poles of a magnet. When the same pole of permanent magnets are brought together, the magnetic flux lines do the same thing, they try to go "around" each other to get from north to south. As you push them together, the field lines "squish" causing a force as the try to go around each other. 3.) I assume that if you took a piece of pyrolytic graphite while it was levitating and tried to press it down, you would feel the same kind of force you experience from permanent magnets that are facing the same poles. Only the force from the pyrolytic graphite would be much much smaller. Is this correct? Does this happen? 4.)What would happen if a piece of pyrolytic graphite is placed inbetween an N48 magnet and a piece of nickel/iron alloy? Would the flux lines just wrap around PG and pull the metal toward the magnet as if the PG wasn't there? Or would the PG reduce the amount of pulling the metal would see? From your earlier statement it would seem the earlier would happen. However, with my current thinking, I feel that there would be a small reduction in the amount of force the metal would see. Please correct me and thank you very much for your time Charles | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 516 Registered: 12-2004 |
1. Several misconceptions here. Electrons have a quantum mechanical "spin" and it carries angular momentum, but it is quantized, it is always there, and it is either up or down, no matter which direction you look at the electron, unlike a spinning top or the earth, where you can tilt your head and make it look like the north pole is a few degrees off from "up". There are no ferrite metals. A ferrite is an oxide, and is ferrimagnetic, unlike iron or nickel, which are ferromagnetic. This is all covered in the first chapter in the book (and on the web). 2. More misconceptions. In a diamagnetic substance near a magnet, the magnetic lines of force are farther apart than in air. Think of a bubble of air in water, rising away from the attraction of gravity. The bubble is not repelled by gravity. The water just falls into the space where the bubble is, and the air in the bubble moves to occupy the space where the water used to be. The magnetic lines of flux are closer together outside the diamagnetic substance, and farther apart inside it. The lines of force on the side of the diamagnet opposite the magnet are in a high energy state (farther from the magnet than they would be if the diamagnetic substance was not there). They can "fall" towards the magnet if the diamagnetic substance moves away from the magnet, just like the water can fall if the air moves away from the earth. So, just as the air bubble moves away from the earth to allow the water to find a lower energy state, the diamagetic substance moves away from the magnet to allow the magnetic lines of force to get closer to the magnet and achieve a lower energy state. 3. The force on the PG is enough to keep it above the magnet. When you push it down, it springs back up. Magnetic repulsion falls off with the third power of distance. Diamagnetic repulsion falls off with the fourth power of distance. 4. The PG would spit out sideways like a watermelon seed, being repelled by both the magnet and the steel, which has become a temporary magnet while in the magnetic field of the permanent magnet. | ||||||||||||||||||||
| Charles Van Neste Unregistered guest |
Ah that clears some things up. Thank you again for your time. Thanks, Charles | ||||||||||||||||||||
| ilija Ilievski Unregistered guest Posted From: 62.220.217.86 |
Is it posible to do this expirement with electromagnets and a lead instead pg? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 641 Registered: 12-2004 |
Electromagnets and a what? | ||||||||||||||||||||
| ilija Ilievski Unregistered guest Posted From: 24.171.76.44 |
lead duh | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 642 Registered: 12-2004 |
I don't understand what a lead is in this context. I can't even tell if you are referring to the element with atomic number 82, or to a tether, or to a single wire used to connect electronics. If the latter, why only one, and why no mention of a battery or some electronics and a sensor? Please describe more fully what you are asking about, so someone can actually help you. A full paragraph provides enough redundancy that we can figure out what you mean despite spelling and grammar errors. In fourteen words you have managed to make two spelling errors that we can easily figure out, and a grammar or spelling error that we cannot figure out. If you want help, you will have to provide more information in your questions, and pay a little more attention to your ability to communicate. | ||||||||||||||||||||
| T Scott Unregistered guest Posted From: 216.146.125.30 |
i have a question about pyrolytic graphite. if you placed a piece between two magnets would it break the magnetic attraction between the two. Like if you would stack them ns|pyrolytic graphite |ns would the two magnets still attract to each other between the pyrolytic graphite or not. thank you | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 652 Registered: 12-2004 |
Only by a tiny bit. More of the field would go around the PG, and less through, but it would all get there. If you want to block a magnetic field, put it in a steel box. | ||||||||||||||||||||
| T Scott Unregistered guest Posted From: 216.146.125.30 |
thank you very much | ||||||||||||||||||||
| Aaron Unregistered guest Posted From: 70.242.171.227 |
I'm doing a science project for physics and want to test different materials for (different strengths of) diamagnitism. I know that PG is good stuff, and bismuth is next but what are some other diamagnetic materials? Great site by the way, best deals on PG I've ever seen. | ||||||||||||||||||||
| Anonymous Posted From: 144.134.89.240 |
Check the above messages, you question has already been answered | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 673 Registered: 12-2004 |
To save you the trouble:
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| Anonymous Posted From: 219.95.252.119 |
I am having trouble with the magnet spinning between two pieces of pyrolytic graphite, separated by a small piece of wood. Can you explain more detail? | ||||||||||||||||||||
| Ben Dover Unregistered guest Posted From: 204.73.103.253 |
I am doing a science fair project using your directions for the levitating magnets. I was just wonder what some of the applications to real life it has. I know that levitating magnets are being used for trains, but do they use levitating magnets for anything else? Ben Dover | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 674 Registered: 12-2004 |
It is the same setup as the previous levitator (the one that uses bismuth). You just replace the bismuth with the PG. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 675 Registered: 12-2004 |
There are displays that levitate merchandise for store windows. Some levitators are used as inclinometers. | ||||||||||||||||||||
| FrancisD (Unregistered Guest) Unregistered guest Posted From: 67.180.42.104 |
Boy you (Sfield) are one hell of a patient guy! I bought the PG with 4 magnets and the levitation works perfectly (I obtained the N-S orientation using a conventional magnet). I split the PG in half and then half again using an ordinary old swiss army knife. My only comment is that these tiny magnets are very very very strong - My kids are 8 and 12 and separating these magnets is tough for me and will probably be impossible for an average 8 year old. Also, just to underscore, when these puppies decide to come together, they rip right at each other and little fingers could get badly bruised! I am still going to let them play with these though because this levitation is "too cool for school". | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 733 Registered: 12-2004 |
Place the magnets on a steel surface, such as an old Altoids tin or the top of a tin plated steel can. That way the magnets will stick to the steel, and not go flying off or pinching fingers. The other advantage to the Altoids tin is that it can act as a container for the whole project. | ||||||||||||||||||||
| JerryWasHere (Unregistered Guest) Unregistered guest Posted From: 66.189.152.139 |
1. Has anyone done material properties of Super Cooled Pyrolytic Carbon? 2. Has anyone tried to make Pyrolytic Diamond from Pyrolytic Graphite? 3. Has anyone tried to make Pyrolytic Graphite and Bismuth foil layers together as a sandwiched substrate? Thanks Jerry | ||||||||||||||||||||
| anom (Unregistered Guest) Unregistered guest Posted From: 24.15.85.118 |
what if you cut the pg in to a triangle instead of a square ? what woudl happen would it spin? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 856 Registered: 12-2004 |
It is a simple experiment to try. | ||||||||||||||||||||
| justine aquino (Mnado) Intermediate Member Username: Mnado Post Number: 41 Registered: 12-2005 |
what would be the positions of the magnet? | ||||||||||||||||||||
| ryan arlis (Gamer49) New member Username: Gamer49 Post Number: 1 Registered: 12-2005 |
i only bought 1 piece of PG so i dont want to waste it and the normal arrangment sns nsn sns or nsn sns nsn | ||||||||||||||||||||
| anom (Unregistered Guest) Unregistered guest Posted From: 24.15.85.118 |
but do u have any idea what it MIGHT do becaues i only ordered 1 peice of pg and i dont want to waste it . | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 865 Registered: 12-2004 |
One piece of PG should make at least 4 floating squares. Cutting one of them in half as an experiment sounds worthwhile to me. | ||||||||||||||||||||
| ryan arlis (Gamer49) New member Username: Gamer49 Post Number: 2 Registered: 12-2005 |
i was thinking more of a equilateral/acute triangle . i would try it and i probly will but i dont have the 4 gold plated neodymium magnets that u use so the effects will probly be much diffrent | ||||||||||||||||||||
| justine aquino (Mnado) Intermediate Member Username: Mnado Post Number: 49 Registered: 12-2005 |
can you use pg for magnet in mid air project? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 868 Registered: 12-2004 |
It works great for that. | ||||||||||||||||||||
| anounomous (Unregistered Guest) Unregistered guest Posted From: 204.73.103.253 |
I am doing the bismuth levitation project, and my magnet just slightly hovers either on the top bismuth plate or the bottom and is never more than a millimeter in the air.How can I get it to levitate higher?I have tried moving the rod up and down but it will not levitate in the middle. When i take the bismuth plates away, the magnet still hovers the same distance off the wood, what is the point of the bismuth plates? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 892 Registered: 12-2004 |
You are placing the plates too far from the floating magnet for the strength of the top magnet. You need to either increase the strength of the top magnet, or bring the plates closer to the floating magnet (or both). The diamagnetic plates stabilize the levitation by preventing the floating magnet from leaving the place where gravity is cancelled by the magnetic field. Without them, the floating magnet will either fall to the ground, or rise to the top magnet. All of this is explained in the book and on the web site. | ||||||||||||||||||||
| anonoumous (Unregistered Guest) Unregistered guest Posted From: 81.77.128.58 |
Can you actually put the levitator big magnet at the bottom instead of the top will that still work? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 899 Registered: 12-2004 |
No. The top magnet does two things: 1. It counteracts gravity by lifting the floating magnet. 2. It keeps the floating magnet centered because moving away from the center also moves away from the top magnet. Having a magnet at the bottom pushing up would not keep the floating magnet centered -- it would do the opposite. | ||||||||||||||||||||
| Soumitra Dan (Unregistered Guest) Unregistered guest Posted From: 24.6.250.81 |
I am trying to decide between 4-magnet and 9-magnet levitation packages for my project. Can you explain what the 9-magnet version does that the 4-magnet one does not. This will help me decide which one to buy. Thank you for your help. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 909 Registered: 12-2004 |
Two things. 1. The pyrolytic graphite aligns with the magnets, instead of in a diamond orientation. 2. You can put 4 pieces of PG at the 4 intersections, instead of one above the middle magnet. | ||||||||||||||||||||
| Jet (Unregistered Guest) Unregistered guest Posted From: 70.142.37.206 |
I want to use the spinning magnetic cube for my Science Project. My dad purchased 2 of the #3 Bundle Kits and several pieces of graphite. We used 2 pieces of graphite with a small piece of wood between them. We placed the small gold cube (2mm) between the graphite pieces. I have the larger magnetic cube (12mm)which I just held above the two pieces of graphite. The small magnetic just flies up and sometimes out. I already broke one of them. What am I doing wrong. I have to build this thing by Monday. HELP! | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 963 Registered: 12-2004 |
The top magnet needs to be farther away. You can find out just how high by holding it in your hand above the small magnet and getting closer until the small magnet just starts to move. | ||||||||||||||||||||
| Brice (Unregistered Guest) Unregistered guest Posted From: 71.255.165.22 |
I have a comment & question about your answer from above: --------------- Q: Can you actually put the levitator big magnet at the bottom instead of the top will that still work? A: No. The top magnet does two things: 1. It counteracts gravity by lifting the floating magnet. 2. It keeps the floating magnet centered because moving away from the center also moves away from the top magnet. Having a magnet at the bottom pushing up would not keep the floating magnet centered -- it would do the opposite. --------------- People involved in the flying frog demo have also demonstrated diamagnetic stabilized magnetic levitation using magnet configurations different from the one you use here. In one configuration they used a short vertical tube of bismuth and the levitated magnet hovered inside the tube -- no bismuth above or below. The diamagnetic bismuth was providing horizontal stabilization. It kept the levitated magnet centered rather than keeping it from flying up or down. They were using a ring shaped lifter magnet from above, so of course the fields are different shapes than with the stacks of cubes used here. But it makes me wonder if you couldn't put the "lifter" magnet underneath the levitated magnet and use the PG to provide horizontal stabilization. There are PG foils (eg Panasonic via Digikey) available, and if only the outer layers provide diamagnetic "forces", a foil tube could be enough. Or 3-4 small pieces of thick PG arranged as a square or triangular tube might work as well since the PG would be oriented properly towards the hovering magnet. The trick would be finding the right height and centering the PG tube over the "lifter" magnet. If the tube was only a little wider than the levitated magnet, then the magnet may not be able to move far enough to be flipped. A longer rod magnet inside the tube might better resist any flipping, even with sloppy construction. I don't know if this would be more likely to work over a single sqaure lifter or a group of four square lifters. Using a ring lifter underneath might be very different from either. Anyhow, I don't have the materials to tinker myself, so I'm simply asking if there's really anything against the lifter underneath configuration if you use the PG to provide horizontal stabilization? It might be easier to construct than your your current kits, although a rod magnet floating in a PG tube may not look as impressive. In any case, it would certainly be instructive to show that the effects work in more than one configuration. I'm posting because I read your site and the below paper within a day of each other... http://www.physics.ucla.edu/marty/diamag/ajp601.pdf (see page 11 esp. -- note I could only follow this paper in the most general terms) P.S. You've got a great sci-ed site! | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1075 Registered: 12-2004 |
No. With the magnet on the top, the floating magnet does not want to flip. With the magnet on the bottom, the floating magnet wants to flip over. The force making it flip is very strong, and the force resisting the flip is the very weak diamagnetic force of the bismuth or PG. The magnet will start to flip, until it touches the walls of the tube. Then it will stay stuck there. | ||||||||||||||||||||
| Ben Rainbow (Benr) New member Username: Benr Post Number: 1 Registered: 5-2006 |
Hi quick question about the pyrolytic graphite, it seems from what i've been reading that it's a much better heat conductor than copper but only in a certain direction. as this seems to be the only place you can buy it at a realistic price is there any chance you could explain which way would provide the best heat conduction on something like the "50 mm Square of 3 mm" of pyrolitic graphite ? im guessing it needs used in the opposite way to the levitating magnet but im not entirely sure (flipped on its side ?) and am i correct in thinking this material is non-porus as well thanks in advance for any light you can shed on this, and hopefully for a intresting evenings work. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1194 Registered: 12-2004 |
It may be the second best heat conductor period, next to diamond. It is fun to take a piece in your fingers, and cut an ice cube with it. Your fingers get freezing cold warming up the PG, but the place where the PG meets the ice is a thin line, so the ice melts quickly. The PG is most conductive in the cleavage plane, but it is still quite conductive perpendicular to it, so you can get quite a bit of heat from your fingers to conduct to a thin line on the ice. It really is fun and amazing. | ||||||||||||||||||||
| Dan Williams (Danpchef) New member Username: Danpchef Post Number: 1 Registered: 5-2006 |
I am building a rectangle magnet levitation vehicle 2 1/2 inches in width 6 inches in length. We are going to have a race on a track, and I wanted to find out where to put the magnets on the bottom to make the vehicle go really fast. We are building prototypes, would it matter if I built it out of acrylic, plywood, or pine? I also wanted to find out if a fin on top would make the vehicle go faster. | ||||||||||||||||||||
| James Lee (Necrofear) New member Username: Necrofear Post Number: 1 Registered: 8-2006 |
Hi. I am having trouble with Pg and i cant tell which side is south and wich is north i am having lots of trouble and i cant pull the magnets apart it is so hard to do it. I need your advice and i need to know how u can tell which way is south and which one is north. Thanks | ||||||||||||||||||||
| James (Magnets) Intermediate Member Username: Magnets Post Number: 46 Registered: 6-2006 |
simple Just get a compass and align th commpas with the poles. If you don't have a compass get PG and try floating the PG on one of the cube's sides, if you put the PG on a pole it should easily slide off. As for pulling apart the magnets, i personally had to get pliers and wrench them apart. For small magnets they are really strong. You can veiw this video i made to see how to to tell which side is a pole
The video quality isn't "GREAT" but i think you get the idea. | ||||||||||||||||||||
| Alex Roberts (Whoo_mythbusters) Senior Member Username: Whoo_mythbusters Post Number: 150 Registered: 9-2005 |
Depending on how big the magnets are the easiest way I found is to slide them apart not just pull. Use the edge of a table or counter to hold one magnet and then push down to slide them apart. | ||||||||||||||||||||
| James Lee (Necrofear) New member Username: Necrofear Post Number: 2 Registered: 8-2006 |
So JAmes (magnets) the video you showed me about the poles. well i was wondering that the side of 1 magnet that levitates the PG is two magnets that levitate it and two that doesnt??? G=1 magnet side that makes the PG levitate H= 1 magnet which side does not let it levitate is it like this??? GH HG or GG HH | ||||||||||||||||||||
| James Lee (Necrofear) New member Username: Necrofear Post Number: 3 Registered: 8-2006 |
on the drawing i meant GH HG or GG HH | ||||||||||||||||||||
| James (Magnets) Intermediate Member Username: Magnets Post Number: 47 Registered: 6-2006 |
no no no In order to levitate PG, 4 poles from 4 of the magnets must face the PG. I doesn't matter which pole, north or south. They must be arranged like this- NS SN or SN NS I have a video here of the PG levitating
PG levitates on the magnets because it wants to be as far away from a magnetic field as possible. The place where the magnet has strongest magnetic fields is at the poles. This forces the PG to float towards the middle. | ||||||||||||||||||||
| James Lee (Necrofear) Junior Member Username: Necrofear Post Number: 4 Registered: 8-2006 |
James. how do you know which one is south and which is north??? that is the real answer i hav been looking for. | ||||||||||||||||||||
| James Lee (Necrofear) Junior Member Username: Necrofear Post Number: 5 Registered: 8-2006 |
I am sorry for asking so much questions! I dont mean to bother you like this! | ||||||||||||||||||||
| James Lee (Necrofear) Junior Member Username: Necrofear Post Number: 7 Registered: 8-2006 |
I really need to know how u can tell which one is south and which is north. Sorry for asking so many questions | ||||||||||||||||||||
| James (Magnets) Intermediate Member Username: Magnets Post Number: 48 Registered: 6-2006 |
No its fine you ask questions, I don't mind. Your not bothering me. You can check which side is a south or a north pole by using a compass. You could just buy a cheap one if you don't have one. You could also try an electomagnet. | ||||||||||||||||||||
| James Lee (Necrofear) Junior Member Username: Necrofear Post Number: 8 Registered: 8-2006 |
but when you get a compass wat do u do with it like do u put the compass on the magnet or comething??? I still think i am bothering you but thank you. LOL | ||||||||||||||||||||
| James (Magnets) Intermediate Member Username: Magnets Post Number: 49 Registered: 6-2006 |
no really your not . Go to this link- http://video.google.com/videoplay?docid=-6789885958250085638&q=electromagnet&hl=en. About 7 minutes and 37 seconds they talk about how to use a compass to figure out what pole is a north or south pole. In this video they try it on an electomagnet but it works with any type of magnet. | ||||||||||||||||||||
| James Lee (Necrofear) Junior Member Username: Necrofear Post Number: 9 Registered: 8-2006 |
omg ty so much for that video it helped so much and i only need a compass! ty so very much and can i hav ur email plz??? | ||||||||||||||||||||
| James (Magnets) Intermediate Member Username: Magnets Post Number: 50 Registered: 6-2006 |
Why? You going to spam me ? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1446 Registered: 12-2004 |
You don't need to know which end is north or south. Once you have assembled the magnets properly, you will see that if you rotate the set of four magnets by 90 degrees, the pole positions have exchanged places. All that is required is that the poles alternate. This is easy to determine using only two magnets -- the poles that attract one another are opposite, so they go next to one another. The poles that push away from one another go diagonally. You can tell which face is a pole easily -- that face attracts metal and other magnets more than the non-pole faces do. Take two magnets, one in each hand, and let them attract one another (while keeping them from jumping together). Their opposite poles will attract. Gently bring them together so they touch pole faces. Now bring another magnet to them, and gently let it join the other two to form a tower, again wil the pole faces touching. Do the same with the last magnet. Now you have a tower of four magnets, and all of their poles are aligned. Each magnet will have its north pole facing the same direction as all the others. The south pole will face the other way. Now put a piece of paper on a steel surface, such as a stovetop or a filing cabinet. Remove one magnet from the stack carefully, and without turning it over, place the face that was attached to the other magnet onto the paper. Then remove the next magnet, and turn it over as you place it on the paper, so that it has the opposite pole facing up. Slide it over to touch the first magnet. The steel will keep them from jumping together and breaking. Do the same with the other two magnets, so the poles are now either NS SN or they are SN NS | ||||||||||||||||||||
| James Lee (Necrofear) Junior Member Username: Necrofear Post Number: 10 Registered: 8-2006 |
James (magnets) can i plz hav ur email??? TY SIMON AND JAMES FOR UR HELP IT HELPED ME SOOOOOOOOOO MEUCH I FINALLY GOT IT TO FLOAT AND I HAVE A QUESTION: wen people need help can i help them also so it is easier for you 2??? | ||||||||||||||||||||
| Alex Roberts (Whoo_mythbusters) Senior Member Username: Whoo_mythbusters Post Number: 151 Registered: 9-2005 |
You can help anyone any time on this site, that's why it is a message board, so everyone can help everyone. | ||||||||||||||||||||
| James Lee (Necrofear) Member Username: Necrofear Post Number: 11 Registered: 8-2006 |
umm ok ty alex but could you help me get james (magnets) email and can i hav urs also??? Sorry if i ask too much questions | ||||||||||||||||||||
| James Lee (Necrofear) Member Username: Necrofear Post Number: 12 Registered: 8-2006 |
Alex let me ask one more thing i bought both ur books on amazon and i was wondering if it contained everything in this website??? i didint get the books yet i should get em tomorrow so iwas wondering wat it had | ||||||||||||||||||||
| James (Magnets) Advanced Member Username: Magnets Post Number: 52 Registered: 6-2006 |
Simon I know it doesn't matter which pole is which. I was just trying to tell him how he could figure it out anyway. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1448 Registered: 12-2004 |
I add projects until there are enough new ones for a book. Books take a while to get published, so there are always a few projects on the site that are not in books yet. | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 26 Registered: 8-2006 |
umm so simon is there ideas that are not on the website also??? | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 27 Registered: 8-2006 |
simon can i ask you sonething?? i bought the levitation bundle #1 and it is supposed to ocme with 4 magnets and i also bought the gauss rifle so i am supposed to hav a total of 8 magnets right??? | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 28 Registered: 8-2006 |
i know it is either 8 magnets or ten | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 29 Registered: 8-2006 |
i know it has to be either 8 or 10 magnets but i only got 6 and i was wondering how i could get the rest of the magnets | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 30 Registered: 8-2006 |
Simon do you know how to get the magnets that scitoys didnt ship me??? | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 31 Registered: 8-2006 |
i also printed the receipt of what i bought and i just bought something like 5 minutes ago on 8/29/2006 and 18:04:09 and i used a visa i guess that is enough information | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 32 Registered: 8-2006 |
sorry but i forgot something... The magnets that you didnt ship me... i was wondering if you could send them with the order i placed on the time and date i gave you | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 33 Registered: 8-2006 |
I am sorry simon but let me ask you one more thing... in your catalog if you click magnets and levitation and if you scroll down to levitation bundle 1... you see the magnets separated but a piece of white thing... what is the white thing | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 34 Registered: 8-2006 |
TY and sorry for all the questions i ask | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1455 Registered: 12-2004 |
The message board is not the place to ask questions about packing screw-ups. It is for helping people with projects, and for getting help from the whole community. They can't help you get what you paid for -- for that, send me email directly. Include the order number, and we will fix the problem right away. | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 35 Registered: 8-2006 |
ty so much!!! i also sent you an email but you didnt respon well anyway ill send you one so when you get this message please check your mail... and please respond as soon as possible | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 36 Registered: 8-2006 |
my email is necrofearballer@yahoo.com just to let you know | ||||||||||||||||||||
| James (Magnets) Advanced Member Username: Magnets Post Number: 58 Registered: 6-2006 |
ha Lee has a mouthful of questions | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 42 Registered: 8-2006 |
James! LOL Rofl | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 43 Registered: 8-2006 |
let me tell you this james having a lot of questions is a good thing | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 44 Registered: 8-2006 |
and lots of questions could lead you to stuff you never realized so that means... | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 45 Registered: 8-2006 |
INVENTIONS!!!!!!!!!!!!!!!!!!!!!!!!!!!!! | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 46 Registered: 8-2006 |
also inventions and discoveries make you famous | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 47 Registered: 8-2006 |
so in a sense questions are a good thing | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 48 Registered: 8-2006 |
so dont make fun of me for asking alot of questions ! LOL i am just playin if ur emotionally hurt lol | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 49 Registered: 8-2006 |
james how did u put that smiley on there??? oh nm i got it | ||||||||||||||||||||
| James Lee (Necrofear) Intermediate Member Username: Necrofear Post Number: 50 Registered: 8-2006 |
ty simon for everything | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 51 Registered: 8-2006 |
Simon ur the best!!!!!!! | ||||||||||||||||||||
| James (Magnets) Advanced Member Username: Magnets Post Number: 60 Registered: 6-2006 |
Oh i ask a lot of questions Lee. Some on this forum and some to Simon although not too much to simon lately. Now that i think of it i used to send Simon an e-mail daily. Makes me feel kind of bad now cause i used to ask him so many questions like overload. Now that i think of it again i can't believe where i am from just 1 experiment i did last year back in December... (Message edited by magnets on August 29, 2006) | ||||||||||||||||||||
| Alex Roberts (Whoo_mythbusters) Senior Member Username: Whoo_mythbusters Post Number: 153 Registered: 9-2005 |
That's just it, you really do feel great after you complete a project, and if done right, like the projects on here, you can learn so much. When I first started posting here I knew so little about electronics it wasn't even funny, but now ,about one and a half years later, I have my Ham licence, and a deep understanding of electronics and science. But I still have A LOT to learn. Just one project at a time. KD8EDR | ||||||||||||||||||||
| James (Magnets) Advanced Member Username: Magnets Post Number: 63 Registered: 6-2006 |
"That's just it, you really do feel great after you complete a project, and if done right, like the projects on here, you can learn so much." Really true. When ever i acomplish a project i feel great that i finally did it and i usually do learn a lot. I never think of physics as complex equations, but just as a quest for knowledge. The first true experiment i ever attempted was this one(http://www.fourmilab.ch/gravitation/foobar/). Easily one of the best experiments i ever done. It tought me how gravity worked and how it was universal. It also tought me that i could predict things with numbers and equations, in this case mass1*mass2/r^2*G. Gravity is a small force and i was even able to translate the small force of a dyne to a gram to a pound by myself. I'm telling you if it wasn't for this project i wouldn't be what i am today!! I would tell you the whole story about how i really got involved but it gets long and i don't think you guys are up for it. | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 52 Registered: 8-2006 |
umm hey james is does simon take ur emails cuz i sent him one and he wont respod! | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 53 Registered: 8-2006 |
umm simon did u get my email??? | ||||||||||||||||||||
| Alex Roberts (Whoo_mythbusters) Senior Member Username: Whoo_mythbusters Post Number: 154 Registered: 9-2005 |
If it is worth responding to your email he will, but he does not sit waiting to receive emails all day. He does have a job, and a family so be patient. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1460 Registered: 12-2004 |
I received your email, and responded here and to your order, which had a parent's email address on it. However, I get thousands of spam emails each day, and some mail may look like spam to my filters. There is also the possibility that the mail I send to someone ends up in their spam filter. | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 54 Registered: 8-2006 |
umm simon can i ask one more thing??? umm... in the same order number i gave you because of thoses 2 magnets i was wondering because i have 10 small tiny bead magnets and i also bought the ring launcher kit so i was wondering how many bead magnets i am supposed to get. i only have ten and i am not trying to lie to you so i can get more i just was wondering and plz dont spam necrofearballer@yahoo.com i will send you an email right now | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 55 Registered: 8-2006 |
Thank you simon and i am sorry for posting here | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 56 Registered: 8-2006 |
umm simon u there? | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 57 Registered: 8-2006 |
floating pg is awesome | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 59 Registered: 8-2006 |
hail pg | ||||||||||||||||||||
| Alex Roberts (Whoo_mythbusters) Senior Member Username: Whoo_mythbusters Post Number: 158 Registered: 9-2005 |
I know it is fun to post and everything, but "hail pg" ??? :-P Ha Ha | ||||||||||||||||||||
| James (Magnets) Advanced Member Username: Magnets Post Number: 70 Registered: 6-2006 |
i'm waiting for the day when we can float anything on a magnet. Image being repeled into the air by a magnet. | ||||||||||||||||||||
| Alex Roberts (Whoo_mythbusters) Senior Member Username: Whoo_mythbusters Post Number: 160 Registered: 9-2005 |
ummm...right | ||||||||||||||||||||
| James (Magnets) Advanced Member Username: Magnets Post Number: 71 Registered: 6-2006 |
ya your right.. that day will never come | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1464 Registered: 12-2004 |
Unless you're a frog. There are 10 magnets in a ring launcher. | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 62 Registered: 8-2006 |
wt heck is a frog??? | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 63 Registered: 8-2006 |
omg simon ur so ................well nm my brother hid them from me and i found em thank you for the frog comment.......... | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 64 Registered: 8-2006 |
killa | ||||||||||||||||||||
| James (Magnets) Advanced Member Username: Magnets Post Number: 73 Registered: 6-2006 |
Simon, even a frog is difficult to levitate and from my point of veiw has only been done by one magnet. To bad you can't make things more diamagnetic. | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 65 Registered: 8-2006 |
how do u levitate a frog? | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 66 Registered: 8-2006 |
is it even possible? | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 67 Registered: 8-2006 |
do you levitate them with the square magnets that scitoys sell??? | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 68 Registered: 8-2006 |
i dont think its possible | ||||||||||||||||||||
| James Lee (Necrofear) Advanced Member Username: Necrofear Post Number: 69 Registered: 8-2006 |
plz can you tell me how you levitate a frog | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1469 Registered: 12-2004 |
Come on, read the article. You need a 20 Tesla Bitter Solenoid and enough power for a small city, not to mention a river to cool it. | ||||||||||||||||||||
| James (Magnets) Advanced Member Username: Magnets Post Number: 74 Registered: 6-2006 |
To levitate anything besides PG is really difficult and requires a extremely strong electromagnet that is constantly cooled due to the amount of heat generated by the current in the coils. You could make the wires superconduct but if the electromagnet creates to strong of a field then the superconducting wires stop being superconductive which means energy loses due to heat. To build something like that is only a dream to most people. It would be easier and A LOT cheaper to levitate a magnet over a superconductor. (Message edited by magnets on September 4, 2006) | ||||||||||||||||||||
| Dipali Thakkar (Dipalithakkar) New member Username: Dipalithakkar Post Number: 1 Registered: 10-2006 |
I have purchased the toy to levitate PG on the four magnets, it works very well. I was interested in knowing the B, H and Relative Permeablity of the magnets. I would also like to know the Relative Permeability and Suceptibility of PG. I require these as I wish to do force calculations for the this setup. Help would be really welcome. Thankyou, Dipali | ||||||||||||||||||||
| Dipali Thakkar (Dipalithakkar) New member Username: Dipalithakkar Post Number: 2 Registered: 10-2006 |
Could you please reply as soon as possible ? This is a sincere request. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1552 Registered: 12-2004 |
Magnets: Br is 1.532 Teslas residual flux density. Bd is 0.712 Teslas Hd is 7130 Oersteds (Bd times Hd) is 50,765,600 GaussOersteds (50.76 MGOe). Pyrolytic Graphite susceptibility is -0.00045. | ||||||||||||||||||||
| Dipali Thakkar (Dipalithakkar) New member Username: Dipalithakkar Post Number: 3 Registered: 10-2006 |
Thank you for the inputs, will be a great help. Thanks and REgards, Dipali | ||||||||||||||||||||
| Kyle Hughes (Kyle_hughes) New member Username: Kyle_hughes Post Number: 1 Registered: 12-2006 |
Good day Simon, I just finished reading this post and decided to put up another with a few questions I have about diamagnetic materials. I have created a lab design to test if temperature would affect the amount of repulsion on diamagnetic materials. I was thinking of using about 5-8 different materials to do this. I am considering to buy some bismuth and pyrolitic graphite from this website but where else could i find easily abtainable diamagnetic materials. Also i was wondering if you can give me some input on how you feel a lab like this would turn out? | ||||||||||||||||||||
| James (Magnets) Senior Member Username: Magnets Post Number: 121 Registered: 6-2006 |
"Also i was wondering if you can give me some input on how you feel a lab like this would turn out?" Well i can give an answer The temperature would affect the dimagnetic affect of the material. The colder the material is the more repulsion you should get. "I am considering to buy some bismuth and pyrolitic graphite from this website but where else could i find easily abtainable diamagnetic materials?" You really can't find other good dimagnetic materials anywhere but on the internet. | ||||||||||||||||||||
| Kyle Hughes (Kyle_hughes) New member Username: Kyle_hughes Post Number: 2 Registered: 12-2006 |
Thank you very much, yes well i was just making sure that there would be some change so i can show it graphically, why exactly would this change occur though, what inside the diamagnetic material would incur this change. I was wondering if anyone had some sources on this as i do have to write a 3000 or so lab report on this... Also if being heated up im guessing the repulsion would be less right? Yeah i live in South America how would delivery to Chile work out? Who should i talk to? (Message edited by kyle_hughes on December 11, 2006) | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1595 Registered: 12-2004 |
We ship all over the world. Most of the right half of the periodic table is diamagnetic: "http://www.aacg.bham.ac.uk/magnetic_materials/type.htm". Thus copper, silver, gold, mercury, sulfur, silicon, gallium, indium, germanium, lead, cadmium, and zinc are all diamagnetic to some extent, as are the halogens and the noble gases, and a few other elements. Diamagnetism is an effect caused by the orbits of inner electrons, and is not affected by temperature. Temperature affects paramagnetic and ferromagnetic materials by interfering with the alignment of magnetic moments. There is no temperature dependent alignment in diamagnetism. Impurities in the diamagnetic materials may have paramagnetic or ferromagnetic properties, and increased temperature will affect these impurities linearly, according to the Curie-Weiss laws. If this happens, then I would expect a slight increase in apparent diamagnetism as the effect of the impurities is lessened by increased temperature. One thing to control for is the temperature of the lifting magnets. They are strongly affected by temperature, and will weaken as the temperature rises. This can be mistaken for a lessening in the diamagnetic properties of the material under test if the temperature of the lifting magnet is not carefully controlled. You might consider using an air core copper coil instead of a magnet. "http://www.google.com/search?q=diamagnetic+%22temperature+independent%22" | ||||||||||||||||||||
| Kyle Hughes (Kyle_hughes) New member Username: Kyle_hughes Post Number: 3 Registered: 12-2006 |
So do you think if i changed my experiment into searching how the temperature affects ferro/paramagnetic materials instead would be more worthy? Also what exactly to you mean by "lifting magnets"? Are you talking about magnets that are attracted to eachother? | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1596 Registered: 12-2004 |
This is a thread about levitating pyrolytic graphite. Specifically, this project: "http://sci-toys.com/scitoys/scitoys/magnets/pyrolytic_graphite.html" The magnets in that project are referred to as lifting magnets because they are lifting the pyrolytic graphite. The term 'worthy' is subjective. Replicating the work of others is a necessary part of the scientific method, and in either case you will be replicating other work. If your hypothesis is that diamagnetism is independent of temperature, you might prove it is the case, but having your hypothesis proved incorrect is often more interesting. | ||||||||||||||||||||
| Kyle Hughes (Kyle_hughes) Junior Member Username: Kyle_hughes Post Number: 4 Registered: 12-2006 |
Ok thank you very much. But you are saying certain impurities in the diamagnetic substance will cause the change in the "push factor" and not the actual diamagnetic material. How would something like this be proven? Isnt there to much room for error? My basic lab design is to use a mass scale and see how the mass changes when a strong magnet is placed above the diamagnetic substance that is on top of the scale. Then repeat at different temperatures and see the change. Would this work, but even if I did see a change the fact you mentioned the impurities i believe a lab design like this would have to many errors for me to actually explain why the change is occuring... (Message edited by kyle_hughes on December 12, 2006) | ||||||||||||||||||||
| James Cumberbatch (Hedgehog) New member Username: Hedgehog Post Number: 1 Registered: 2-2007 |
Hello I am having trouble getting my PG to levitate using 4 NdFeB cube magnets with a 12mm side (rubber coated) from KJ Magnetics. These magnets have a pull force of 18 lbs. Are they too weak or am I doing something wrong? Thank you Jamie (Message edited by hedgehog on February 9, 2007) | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1636 Registered: 12-2004 |
Measuring magnets in pounds of pull is not very helpful. A larger magnet of the same strength will be able to pull with more force, but that won't help the levitating graphite at all. Our magnets are 50 MegaGaussOersteds in total energy product. In the magnet trade, this is often abbreviated to N50. Your magnets are more likely to be N25 or N30. A rubber coating might also be much thicker than our gold plating. With weaker magnets, the coating may be thicker than the height of levitation, so the graphite would be sitting on the rubber. But before you give up, you should make sure that the poles of the magnet are aligned vertically, and that the north and south poles alternate in which one is up. Looking down on the magnets, the poles would look like NS SN | ||||||||||||||||||||
| Keith Adams (Keith_adams) New member Username: Keith_adams Post Number: 1 Registered: 3-2007 |
Hello, I didn't see it posted on this message board so I thought I'd register and ask. In the 4 magnet/PG experiment, I have seen a 1/4 inch hole drilled into the center of the PG. I would think that this would result in higher lift because of lower weight while still retaining stability. I would also think that the bulk of the material is still located where it is needed most, along the outer edges of the PG square which interacts with the magnetic field lines. Can someone comment on this? Does anyone have any firsthand knowledge in doing something similar (besides cleaving or sanding the PG)? Was any advantage in height gained? Any comments are appreciated before purchasing additional materials. Thanks & keep levitating! Keith Currently using 4 N53 12mm cubes on steel plate | ||||||||||||||||||||
| Keith Adams (Keith_adams) New member Username: Keith_adams Post Number: 2 Registered: 3-2007 |
16 Mar 2007 Update: Using my current setup of 4 N53 12mm cubes on steel plate, I cleaved a 12mm x 12mm x 1mm into 4 separate pieces. Then I drilled a .25" hole in the center of the thinnest piece. Result? My sample of PG now sits 1.75mm above the cubes which is the equivalent of 13 PostIt notes in thickness. Is anyone getting similar results? Using PostIt notes as a standard, how many can you slide between the magnets and the PG without bumping the piece off? Keith | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1662 Registered: 12-2004 |
Without a hole, mine here at Google is sitting 10 Post-Its above my old N48 magnets. I'll have to try it with our new batch of magnets, which are the strongest available. You might want to check your magnets though. Some sellers on eBay are claiming N53, which might be what they were measured at right after being magnetized, but are probably not that good by the time they actually get to you. | ||||||||||||||||||||
| Keith Adams (Keith_adams) New member Username: Keith_adams Post Number: 3 Registered: 3-2007 |
It's good to find other comparisons. I originally had N48 magnets and then purchased N53. Side-by-side I do show a difference in height achieved, but it's not incredibly significant since N53 is only 13% stronger than N48. But it all adds up, right? I have some round PG samples coming in and I would really like to crack the 2mm barrier. If anyone else can measure heights achieved with PostIts, please check in with your results. Keith | ||||||||||||||||||||
| Keith Adams (Keith_adams) Junior Member Username: Keith_adams Post Number: 4 Registered: 3-2007 |
It appears I have found a way and cracked the 2mm barrier with the standard setup of 4 .5 inch cubes. After reading about some experiements by a UCLA physics team, they were trying to create a seismometer with magnets and PG, submerged in water to act as a dampener. By using water, the PG motion was definitely dampened, but greater lift was also achieved! With great care, I was able to repeatedly measure conservative heights of 18 PostIt's. Luke warm, ice cold and ice cold water with salt was used during experimentation. Luke warm was better than just an air gap. Ice cold water with or without salt was tied for best. Surprisingly, ice cold salt water didn't appear to win out here. Has anyone continued experimenting with the 4 cube setup? Check in with your results. Thanks! Stay tuned for future experiments. Keith Currently using 4 N53 12mm cubes on steel plate | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1694 Registered: 12-2004 |
The specific gravity of PG is about 2.1. Water is (of course) 1.0. So by immersing the PG in water, you are using buoyancy to reduce the effective weight of the PG. Not exactly news -- the ancient Egyptians used this technique to get levitation of wood products with gaps measured in fathoms. Large parts of the British economy depended on this principle for many years. One of the first major breakthroughs was made by Archimedes, causing him to leap from his bath and run through the streets naked, shouting "Eureka!". And, of course, it has been mentioned before on this message board: "http://scitoys.com/board/messages/9/3361.html". You might try it in Carbon disulfide, or 1,1,2-Trichlorotrifluoroethane or Carbon tetrachloride, or Chloroform, or Citric acid, or Dichloromethane. Or try dropping the whole setup from a height to reduce the effects of gravity. | ||||||||||||||||||||
| Aivars Pumpurs (Aivars) Junior Member Username: Aivars Post Number: 7 Registered: 3-2006 |
Hello Keith! have you read this: http://diamagnetic.levitation.googlepages.com/home.htm Not exactly what you looking for. But good page and even award promised. | ||||||||||||||||||||
| Keith Adams (Keith_adams) Junior Member Username: Keith_adams Post Number: 5 Registered: 3-2007 |
Hey, thanks Simon. As always I can expect to get such helpful answers from you. Thanks! Really. | ||||||||||||||||||||
| Lawrence Dunkel (Lawrencedunkel) New member Username: Lawrencedunkel Post Number: 1 Registered: 5-2007 |
In response to: "Posted on Sunday, June 26, 2005 - 8:09 pm: Simon Quellen Field (Sfield) Post Number: 516 3. The force on the PG is enough to keep it above the magnet. When you push it down, it springs back up. Magnetic repulsion falls off with the third power of distance. Diamagnetic repulsion falls off with the fourth power of distance." Me: As I understand it, gravity falls off with the SECOND power of distance (inverse SQUARE law). This is because of the GEOMETRY of SPACE being THREE dimensional. Can you explain to me how anything can fall off with the THIRD power of distance, or any other power? Also, were these numbers arrived at by theory or experiment? Thanks, Lawrence. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1702 Registered: 12-2004 |
You get inverse square laws when dealing with omnidirectional forces. These are forces that effect things in all directions, and hence the effect is the same if the distance is the same, forming a sphere. The formula for the surface area of a sphere is 4 * pi * the square of the radius. It is that last term that makes the inverse square law. If you double the radius, you square the surface area. The effect is spread over a larger area, so the effect is proportionally weaker, by one over the square of the radius. A magnetic field is not an omnidirectional force. It starts at one pole and curves around to the other. The field lines are very close together at the poles, and farther apart between the two poles. The shape is not a sphere, so the effect is not inverse square. Both the shape of the field and the shape of a sphere are three dimensional, so that has nothing to do with how effects vary with distance. As with gravity, the experiments and observations came first, then the theory was developed to explain the observations. As magnets get farther away from one another, the field does begin to look like a sphere. Now we get another effect happening, that will show you why we get the fourth power. You can think of a diamagnet as a mirror for a magnet. The magnet acts as if it is seeing its mirror image in the diamagnet. Now you can see that as you double the distance between the magnet and the mirror, you quadruple the distance between the magnet and its mirror image. So instead of a square law, we get a square law times a square law, hence the fourth power. Stand a foot away from a mirror. You will see your reflection appears to be two feet from you. Step a foot back so you are two feet from the mirror. Your reflection is now four feet from you. Diamagnetism works the same way. | ||||||||||||||||||||
| Thomas B Jones (Spinnervision) New member Username: Spinnervision Post Number: 1 Registered: 10-2007 |
Simon Quellen Field wrote:
It's much higher now. Been able to easily & cheaply find at 50 MGOe for quite awhile now. And just last week I bought a few in assorted shapes, as they were the first I'd seen for sale anywhere, at 52 MGOe. | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1803 Registered: 12-2004 |
Ours have been 52 MGOe for about the last year. That's the problem with reading old posts. As the technology improves, we will always ride the curve, and offer the best magnets available. | ||||||||||||||||||||
| Joshua Lim (Vdg) Junior Member Username: Vdg Post Number: 10 Registered: 4-2008 |
Mr field, could you levitate bismuth powder mabye 10 angstroms over your NIB magnets or PG powder? Or is bismuth powder too heavy? | ||||||||||||||||||||
| Aivars Pumpurs (Aivars) Member Username: Aivars Post Number: 11 Registered: 3-2006 |
Serious scientists announce that they can levitate microscopic water droplets with Neodymium magnets. Bismuth levitates better than water and graphite is the best. Mass diamagnetic constants are: .....9x10(-9) for Water ....17x10(-9) for Bismuth ....72x10(-9) for Graphite I have not tried to levitate graphite powder, but pure graphite levitates OK. For example some pencil leads levitate 0.1mm above “neo” magnets. So I think powder will also levitate. Use of pyrolytic graphite powder gives approximately the same results as pure graphite powder, because in powder state pyrolytic graphite will loose the anisotropy. | ||||||||||||||||||||
| Kasper Emil Feld (Magnetfeld) Advanced Member Username: Magnetfeld Post Number: 80 Registered: 11-2007 |
It migth even be worse since single crystal powder pieces will adjust to lie paralel to the field. | ||||||||||||||||||||
| Diego Assencio (Diego) New member Username: Diego Post Number: 1 Registered: 10-2008 |
Hi Simon, I need to do some calculations with the 12mm and with the 2mm magnets that I bought from you. I saw you posted some data about them above, but I need to understand it all better. So... is Bd the value of B inside the magnet? Is Hd the value of H inside the magnet? In this case, the magnetization (in metric units) would be M = 1/u0 * B - H, right? Is this magnetization (and also the fields) constant (or nearly constant) all over the volume of the magnet? I already have Bd and Hd for the 12mm, so could you please post these values for the 2mm ones? I would really appreciate it! One last thing: is 50,765,600 GaussOersteds is the energy >density< inside the magnet? Thank you very much for your help! | ||||||||||||||||||||
| Theresa Simmons (Theresa) Advanced Member Username: Theresa Post Number: 71 Registered: 1-2008 |
Hd is the magnetostatic self-interaction. See "http://www.google.com/search?q=magnetostatic+self-interaction+Hd" and "http://www.google.com/search?q=%22magnetostatic%20self-interaction%22" Remanence, Bd: The magnetic induction that remains in a magnetic circuit after the removal of an applied magnetizing force. If there is an air gap in the circuit, the remanence will be less than the residual induction, Br. See also "http://www.magnetsales.com/Design/Glossary.htm" | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1917 Registered: 12-2004 |
The magnets are made from the same material. GaussOersteds is a unit of total energy product. | ||||||||||||||||||||
| Diego Assencio (Diego) New member Username: Diego Post Number: 2 Registered: 10-2008 |
Thank you for the book reference. It was helpful, but I still need to know: a) for these magnets, is the value of M (the magnetization) constant (or nearly constant) all over the magnet? b) When you say they are made of "the same material", you mean they have the same magnetization M? Thank you! | ||||||||||||||||||||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1918 Registered: 12-2004 |
Yes, and yes. | ||||||||||||||||||||
| Diego Assencio (Diego) New member Username: Diego Post Number: 3 Registered: 10-2008 |
So, I created a model using a constant M, and I got a nonuniform B and a nonuniform H inside the magnet. At first I thought that was weird, but it is correct. I guess my question this time is: what is the value of M inside the magnet? If B and H are nonuniform, how would having Bd or Hd help me? I first used Hd = Bd - 4*pi*M to find M, but I see that doesn't make any sense now. I mean... where in the magnet are these numbers calculated? If you could provide me the value of M for the magnets, I would be really grateful since that would solve most of my problems here. Thank you! | ||||||||||||||||||||
| ameya chandekar (Amayroughplayer) New member Username: Amayroughplayer Post Number: 1 Registered: 12-2010 |
hi , I JUST WANT TO KNOW THAT AT WHAT HEIGHT THE PG LEVITATES CAN WE INCREASED THE LEVITATION HEIGHT OF THE PLATE BY INCREASING THE MAGNETIC INTENSITY OF THE MAGNET | ||||||||||||||||||||
| Theresa Simmons (Theresa) Senior Member Username: Theresa Post Number: 166 Registered: 1-2008 |
Yes. Unfortunately, the magnets sold at scitoys.com are the strongest currently available. "http://www.scitoyscatalog.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=LEVKIT1&Category_Code=M" | ||||||||||||||||||||
| ameya chandekar (Amayroughplayer) New member Username: Amayroughplayer Post Number: 2 Registered: 12-2010 |
i have a 4 neodymium magnets of size 5cm x 5cm x 2.5 cm. but i dont have a graphite for levitation .can u please tell me at what height graphite will levitate with neodymium magnets which i have | ||||||||||||||||||||
| ameya chandekar (Amayroughplayer) New member Username: Amayroughplayer Post Number: 3 Registered: 12-2010 |
IS THERE ANOTHER WAY TO ORDER PYROLYTIC GRAPHITE FROM SCITOYS |
which side is a pole