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Levitating frogs - alive ?

  1. Apr 19, 2003 #1


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    Greetings !

    Some time ago I read about all those experiments
    when they used very powerful magnetic fields
    on the order of 10 Tesla (10^5 Gauss) and
    above to make stuff levitate. I also
    saw a picture of a levitating frog.
    My question is - how come that frog stayed
    alive ? Wouldn't such a powerful magnetic
    field totally disrupt its entire nerveous system
    and brain functions ?

    Live long and prosper.
  2. jcsd
  3. Apr 19, 2003 #2
    Just a question:
    How did you know it was alive ?
  4. Apr 19, 2003 #3


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    It moved while being levitated and they
    say it felt quite "fine" after that experience. :smile:
  5. Apr 20, 2003 #4
    i remember seeing the same thing done with a spider. it moved around and everything while they did it
  6. Apr 20, 2003 #5


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    HM...Why do magnetic fields affect these animals? Can a strong enough magnetic field levitate anything?
  7. Apr 20, 2003 #6


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    Diamagnetic levitation.


    Note that this magnetic replusion acts at the atomic scale. Since each atom is acted on by a nearly identical force, the frog feels like it is in free fall.
  8. Apr 20, 2003 #7


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    Yes, but what about the nerve system and the
    brain (based upon electrical signal exchange) ?
    No damage ?

    Live long and prosper.
  9. Apr 20, 2003 #8
    neuroscientist uses up to 7Tesla imaging magnets on animals, 3T on people and that does nothing to you.

    but also we can use magnets to disrupt certain areas of the brain.it's called transcranial magnetic stimulation(TMS). it's relatively new but i'm pretty sure does not use that many Teslas.

    so i think that maybe the orientation of the field may matter in terms of disrupting neural activity. actually i'm pretty sure it does. in TMS you can change the orietation of the field and the effect will go away.
  10. Jul 1, 2004 #9


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    If there is no magnetic flux (either by fast movement through the magnetic field, or by rapidly altering the strength of the field), there will be no effect of electrical interferance.

    In this case the magnetic field is stationary, and the frog is not moving through enough of a magnetic field gradient to cause electrical induction interference, so he is completely fine.

    There are plenty of 'magnetic' therapies products on the market, those employing permanent magnets are completely ridiculous, preying on ignorance and stupidity, and if they are making any claim at all, it is a complete lie.

    However, a pulsed magnet does have an effect on central nervous systems, and people are working on how to apply this in a benificial way.
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