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FLAME DEFLECTED by Permanent Magnet - REASON FOUND BY TOKYO SCIENTISTS

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LAN_403

Sat Feb 10 2007, 05:41PM

Banned on April 7, 2007
Registered Member #277 Joined: Fri Mar 03 2006, 10:15AM
Location: Florida
Posts: 157

Here is a pic of the flame deflection when the strong neo-mag is brought close to the candle flame, in this particular pic, it's two neo-mags in series, which seems to cause a bit more deflection compared to one neo. In this setup, the deflection isn't observed when other items, including weaker neo-magnets, a plate of aluminum, glass, etc, etc, etc, are brought close to the flame. I've recently learned (with the interpretive help of some people here on this board with the below formula) that diamagnetic materials are influenced not only by the strength of the magnetic field, but also the physical size of the magnet that is generating the field, reference

"where d2BZ/dz2 = 0, note that this is a purely geometrical condition, which does not depend on the field strength. The spatial extent of the region of stable levitation is typically a small fraction of the magnetâ€™s size". So maybe, just maybe, the size of the magnet, not just the field strength, plays a role in whether or not flame deflection occurs. CM

ShawnLG

Sat Feb 10 2007, 06:29PM

Registered Member #286 Joined: Mon Mar 06 2006, 04:52AM
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Posts: 399

I have tried this experiment and the flame only move away a very small amount. Not enouff for me to belive that it really works because the iron and magnet I used have different geometric shape and could cause a differents change in the air currents. The only way to test if this really works is to use an electromagnet. I do not have one to test with.

Sat Feb 10 2007, 09:19PM

Banned on April 7, 2007
Registered Member #277 Joined: Fri Mar 03 2006, 10:15AM
Location: Florida
Posts: 157

Hmmm... sometimes it can be difficult replicating test results when not using the same exact test set up. My guess is that you'll need to use a square or rectangular neomagnet of at least 5000 gauss and a Max Energy Product - (BH)Max: 38.72 MGOe to see the same flame deviation that I see (that is what I use). Two of these mags connected in series produces a slightly stronger flame deflection, than one. For those who want to see if they can replicate this demonstration, here is the source and exact magnets I am using in the picture (two of these mags in series)

Also, another reason to try the exact mags above is that diamagnetism (IF that is what is happening to the flame) seems to have a relationship to the physical size of the magnet

formula already mentioned in a post above. For a few bucks to purchase a couple of the magnets, someone could replicate this test exactly and let us know if you get the same flame deviation seen in the picture. Btw, the pic is taken at about 10 feet above sea level at an ambient temperature in the mid 50's F. just in case altitude or air temperature has anything to do with it. Oh, and be careful when allowing the two mags to couple to each other, they can slam together with such force that they shatter, been there, done that. CM

Bjørn

Sat Feb 10 2007, 10:15PM

Registered Member #27 Joined: Fri Feb 03 2006, 02:20AM
Location: Hyperborea
Posts: 2058

What you need to do is to put an aluminium or other non-magnetic plate between the flame and the magnet. If you could also film it as you move the magnet closer to the flame and further away again it would help a lot.

Bored Chemist

Sun Feb 11 2007, 10:01AM

Registered Member #193 Joined: Fri Feb 17 2006, 07:04AM
Location: sheffield
Posts: 1022

OK, so I'm typing this with spots in front of my eyes from staring at candle flames.
I tried agian using a candle rather than a meths burner (after all, one of the possible explanations is the diamagnetism of soot and meths doesn't produce much soot).
The couple of disk-drive magnets didn't seem to have any effect (other than making the flame tall and smokey when they were near enough to cool the flame significantly. I got the same effect with a bit of aluminium).
I then tried the stack of magnets I usualy use for levitating a small magnet between 2 bits of Bi. Its a stack of 30 NdFeB magnets each is a 1/2" by 1/4" dia cylinder and they are held together in a brass tube.
It's a fairly big powerful magnet and it didn't seem to have any effect that I couldn't reproduce with a similar shaped bit of steel.

Of course, this proves nothing It's still not a true repeat of the original experiment.
If I could get the same effect the next thing I might do would be to heat the magnets until they were not magnets any more and see if that made a difference. That might be a purist aproach- the only think changed would be the magnetic field- on the other hand, it would be rather expensive. Just repaeting the experiment with a piece of wood and a piece of aluminium the same size and shape as the magnets would do the job. (Wood's a worse thermal conductor, Al is better so if they both didn't have an effect you would know it wasn't down to thermal effects).
Incidentally, the formula you give is for the equilibrium point of a levitated object AFAICS is a necessary, but not sufficient condition. The field gradient (db/dz) also has to be strong enough because that's what provides the lifting force.
I don't think the condition d2B/dB2=0 is met anywhere along the axis of a cylindrical magnet. The field gets weaker as you go away from the pole and it gets weaker more slowly as you get further away too. d2b/dz2 is always negative and falls with distance. You could only get zero by having another opposing field. (gravity provides the equivalent of this when "levitating", but it does not actualy influence B directly.)

Sun Feb 11 2007, 02:28PM

Banned on April 7, 2007
Registered Member #277 Joined: Fri Mar 03 2006, 10:15AM
Location: Florida
Posts: 157

Another factor that I should mention to those who are trying to replicate this demo is that the neo-magnet deflects the entire flame only when placed near the base of the flame (nearest the candle wick where the flame originates, see above picture). The magnet does not deflect the flame if positioned up higher above the wick. Btw, I froze a metal sheet about 4x5 inches in the freezer for about an hour and then placed it near the flame, no defection. I've tried many materials, cold and at room temp, so far the ultra-strong neo-mags are the only item I've found that deflects the flame. I realize most of us have magnets laying around that we feel are pretty strong, like small neos or disc drive mags, however, the neo-mags in the picture are scary strong. I've recently bought about US$1200 in magnets for experiments, these mags are among the strongest I've ever encountered

they are certainly finger breakers if you happen to get your finger caught in between them. I have several scars on my hands from bleeding cuts I've earned while learning how to handle them properly. CM

Carbon_Rod

Mon Feb 12 2007, 01:17AM

Registered Member #65 Joined: Thu Feb 09 2006, 06:43AM
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Posts: 1155

CM, try it with a different candle.

Strong magnets do affect paramagnetic oxygen, but I suspect this is not the case here.

Cheers,

Mon Feb 12 2007, 07:48AM

Banned on April 7, 2007
Registered Member #277 Joined: Fri Mar 03 2006, 10:15AM
Location: Florida
Posts: 157

Carbon:

Did what you said, used a completely different candle, this time a tall thin candle about one foot in height, same result, the flame is deflected by the ultra- strong neomag. For about US$22 anyone should be able to replicate this demonstration by using the same magnets found at

Steve Conner

Mon Feb 12 2007, 10:35AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Is anyone in the US going to buy those magnets and try to replicate the experiment?

Dr. Shark

Mon Feb 12 2007, 03:38PM

Registered Member #75 Joined: Thu Feb 09 2006, 09:30AM
Location: Montana, USA
Posts: 711

Exactly the same magnets are available in Europe, at least in Germany that is:

scoll down to the bottom. I have two of then, but unfortunately I have them at my parents place, so I cannot replicate the experiment anytime soon.
But really, any selfrespecting geek should have these magnets, they are so much fun to play with!

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