Zero G at Earth Sea Level

The Flying Frog AVI  or the Flying Flowers AVI

 

*


Molecular Magnetism and Levitation.

(The Frog That Learned to Fly)



Seeing is believing:

A little frog (alive !) and a water ball levitate inside a 32mm vertical bore of a Bitter solenoid in a magnetic field of about 16 Tesla at the Nijmegen High Field Magnet Laboratory.


 

(Click on the images to get larger ones)



The image of a high-temperature superconductor levitating above a magnet in fog of liquid nitrogen can hardly surprise anyone these days - it has become common knowledge that superconductors are ideal diamagnetics and magnetic field must expel them. On the other hand, the enclosed photographs of water and a frog hovering inside a magnet (not on board a spacecraft) are somewhat counterintuitive and will probably take many people (even physicists) by surprise. This is the first observation of magnetic levitation of living organisms as well as the first images of diamagnetics levitated in a normal, room-temperature environment (if we disregard the tale about Flying Coffin of Mohammed as such evidence, of course). In fact, it is possible to levitate magnetically every material and every living creature on the earth due to the always present molecular magnetism. The molecular magnetism is very weak (millions times weaker than ferromagnetism) and usually remains unnoticed in everyday life, thereby producing the wrong impression that materials around us are mainly nonmagnetic. But they are all magnetic. It is just that magnetic fields required to levitate all these "nonmagnetic" materials have to be approximately 100 times larger than for the case of, say, superconductors.



Whether an object will or will not levitate in a magnetic field B is defined by the balance between the magnetic force F = MnablaB and gravity mg = rhoV g where rho is the material density, V is the volume and g = 9.8m/s2. The magnetic moment M = (chi/ 0)VB so that F = (chi/0)BVnablaB = (chi/20)VnablaB2. Therefore, the vertical field gradient nablaB2 required for levitation has to be larger than 20 rhog/chi. Molecular susceptibilities chi are typically 10-5 for diamagnetics and 10-3 for paramagnetic materials and, since rho is most often a few g/cm3, their magnetic levitation requires field gradients ~1000 and 10 T2/m, respectively. Taking l = 10cm as a typical size of high-field magnets and nablaB2 ~ B2/l as an estimate, we find that fields of the order of 1 and 10T are sufficient to cause levitation of para- and diamagnetics. This result should not come as a surprise because, as we know, magnetic fields of less than 0.1T can levitate a superconductor (chi= -1) and, from the formulas above, the magnetic force increases as B2.



The water and the frog are but two examples of magnetic levitation. We have observed plenty of other materials floating in magnetic field - from simple metals (Bi and Sb), liquids (propanol, acetone and liquid nitrogen) and various polymers to everyday things such as various plants and living creatures (frogs and fish). We hope that our photographs will help many - particularly, non-physicists - to appreciate the importance of magnetism in the world around us. For instance, it is not always necessary to organize a space mission to study the effects of microgravity- some experiments, e.g. plants or crystal growth, can be performed inside a magnet instead. Importantly, the ability to levitate does not depend on the amount of material involved, V, and high-field magnets can be made to accommodate large objects, animals or even man. In the case of living organisms, no adverse effects of strong static magnetic fields are known - after all, our frog levitated in fields comparable to those used in commercial in-vivo imaging systems (currently up to 10T). The small frog looked comfortable inside the magnet and, afterwards, happily joined its fellow frogs in a biology department.

A.K. Geim, J.C. Maan.
in collaboration with
H.A.Carmona (University of Sao Carlos)
P.C.Main (Universty of Nottingham)




More photographs of levitating objects.

And MOVIES of levitating objects.



The best of the press coverage so far:
"If frogs can fly, there is no reason why John Major cannot be Prime Minister"



And the best of public response so far (have a good laugh!)



  • The work is featured in Physics World, April 1997, p. 28
  • The most complete account is given in "Of Flying Frogs and Levitrons" by M.V.Berry and A.K.Geim, European Journal of Physics, v. 18, p. 307-313 (1997).
  • For further reading, see:
    • "Magnetic Levitation"
    • E.H. Brandt, Science 243, 349 (1989)
    • E.Beaugnon & R.Tournier, Nature 349, 470 (1991); J. Phys. III France 1, 1423 (1991)
    • J.M. Valles et al, submitted to Biophysical Journal.


* Go to the HFML Home Page.


 

Last updated on 23-jul-97 ln

 

Frog

avi works

.AVI or .MOV
Nut
.AVI
Flowers

flowers avi works

.AVI
Water ball
.AVI or .MOV
Grass Hopper
.MOV

/////

Bobby presents another great file of links to other electro-magnetic anti-gravity visionaries:

/////

 

Up to top (try Weird Science!)

Nikola Tesla Page, tesla coils

Hey, congratulations, you found some Tesla stuff on WWW! I highly recommend the listserv run by the International Tesla Society (see below.) If you have Tesla questions, subscribe to the listserve and ask the group. Also check out nic.funet.fi (below) for more files on coils. Serious coilers should subscribe to the T.C.B.A. newsletter, and buy all the back issues too!

This page is part of WEIRD SCIENCE / AMATEUR SCIENCE. Created 12/94. If you have any tesla-oriented files you'd like to see put on the net, feel free to contact me and I'll put them here...

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The files in the list below are available from this Keelynet mirror site, or from the Keelynet BBS itself, phone 214-324-3501. Any disabled files below are only on Keelynet itself, and have not been uploaded to ELEKTROMAGNUM as yet.

Keelynet mirror at ELEKTROMAGNUM, with excellent indexing system

Try Elektromagnum itself, with lots of interesting stuff!

 
TESLAC.ZIP U/L on 01/19/94 Desc    | Tesla Coil Design Program 
Sz = 36864 DL = 50 Last = 08/26/94 | 

TESLACII.EXE U/L on 07/28/94 Desc  | A NEW VERSION OF TESLAC, THE TESLA COIL 
Sz = 59904 DL = 32 Last = 09/15/94 | DESIGN PROGRAM. 

hardy1.asc  U/L on 08/01/92 Desc    | double helix energy emission from a 
Sz = 11150 DL = 19 Last = 06/15/94 |  Tesla coil excited pyramid (see.GIF)
 
TESLA2.ASC U/L on 08/29/90 Desc    | basic Tesla coil theory 
Sz = 4943 DL = 16 Last = 07/30/94  | 

TESLA3.ASC U/L on 08/29/90 Desc    | influence of Vedic philosophy on Tesla's
Sz = 39407 DL = 9 Last = 07/30/94  | work

tesla4.asc U/L on 11/05/90 Desc    | the Scalar Howitzer and a good descript
Sz = 50644 DL = 12 Last = 07/30/94 | of the Tesla wave principles

tesla5.asc U/L on 01/13/91 Desc    | The Greatest Hacker - includes SDI info
Sz = 26058 DL = 12 Last = 07/30/94 | and Tesla Anecdotes 

tesla6.asc U/L on 02/24/92 Desc    | Death Rays and how Tesla probably caused 
Sz = 32610 DL = 10 Last = 06/30/94 | the Tunguska crater, good info....  

teslafe1.asc U/L on 02/01/93 Desc  |Article on the Tesla Power Box as used 
Sz = 28599 DL = 10 Last = 05/19/94 | in a 1931 Packard to drive 80hp AC motor 

teslafe2.asc U/L on 02/01/93  Desc | sysop comments on Tesla Power Box with 
Sz = 15867 DL = 6 Last = 05/19/94  | Moray comparisons 

zap.asc U/L on 08/02/92 Desc       | 2.3 MV Tesla coil experiments with some 
Sz = 10072 DL = 12 Last = 05/20/94 | anomalous observations (see .GIF's) 

TESLAFE1.GIF U/L on 02/01/93 Desc  | shows 
parallel version of Tesla Power 
Sz = 9801 DL = 24 Last = 04/23/94  | Box...conceptual of course 

TESLAFE2.GIF 
U/L on 02/01/93 Desc  | shows SERIES version of Tesla Power 
Sz = 7746 DL = 22 Last = 10/28/93  | Box... 

teslapic    
U/L on 03/18/91 Desc  | Graphics of Tesla Howitzer.  From T.E. 
Sz = 133371 DL = 52 Last = 08/26/94 | Beardens book. IBM's only. Read me file 


Here are three more files from Keelynet which are NOT yet on the 
two mirror sites.  They run on PC compatibles:


TESLABLD.EXE U/L on 06/10/93 Desc  | How to build your own Tesla coil with 
Sz = 57435 DL = 77 Last = 08/28/94 | diagrams and parts list...very good 

TESLAC.ZIP U/L on 01/19/94 Desc    | Tesla Coil Design Program 
Sz = 36864 DL = 50 Last = 08/26/94 | 

TESLACOL.ZIP U/L on 11/29/92 Desc  | program to design your own coil..  
Sz = 110638 DL = 70 Last = 09/12/94 | excellent program!  

Other things here


www.eskimo.com/~billb/tesla/tesla.html is on the Eskimo North service, in
Seattle, WA. Try the Main Eskimo home
page, and users' Individual  home pages
too.  

PLEASE leave comments at: billb@eskimo.com

If you are using Lynx, type "c" to send me a comment. billb@eskimo.com. 

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