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Plasma from a grape in a microwave

  1. Oct 8, 2007 #1
    I'm not sure where to put this,

    Its exactly what the title says:

    this one shows the grape more clearly, starts properly about 1 minute in,

    and also quite long sustained plasma with a match,

    Plasma from a grape! any ideas how? or is it fake?

    also if you watch any of the other similar videos the sustained plasma is only created when there is a glass over it, why? could it be something to do with the resonant frequency of the glass? i noticed it seemed to be sustained longest in glasses with a circular curved bottom section, ones with right angled edges dont seem to work well.
    Last edited by a moderator: Sep 25, 2014
  2. jcsd
  3. Oct 8, 2007 #2


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    Nothing to debunk here (I think, I haven't yet looked at the videos). I too have made "grape plasmas" in a microwave - and without a glass over the grape (I imagine that's to protect the inside walls of the oven from discoloration). The way I do it (see this post), there's two clean grape surfaces that are separated by a fraction of a millimeter near the corner of an air wedge. The electric field between the grape portions at the tip of the wedge is large enough to cause breakdown in the air gap, making a plasma ball there.
  4. Oct 8, 2007 #3
    I'm gonna try that! I've got an old microwave.

    would it be possible to use that sort of mechanism to create a sustained plasma to extract energy from? it looks pretty energetic to me. I suppose its using oxygen mainly for fuel?
  5. Oct 9, 2007 #4
    RA, in order to be a meaningful energy source, the energy extracted has to be a significant portion of the energy put into it. It is unlikely that the energy extracted from two grapes in a micro-wave would be comparable to conventional and/or nuclear methods. Unfortunately, the "fuel" here is the exciting energy coming from the micro-wave oven, which is in turn powered by electricity, which in turn is generated from coal, gas, nuclear power, or some other generating resource. Oh, and the grapes are also consumed by the process.

    Since a plasma is just an excited gas, often created by micro-waves or some other kind of strong EMF, and this is taking place in a micro-wave, it's probably legit. I agree completely with Goku's post.

    Putting a glass over the grape keeps the gas (vapor from the heated grape) from dispersing too quickly, allowing the plasma to last longer. It also, as Goku suggests, protects the inside of the appliance from getting graped-out.
    Last edited: Oct 9, 2007
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