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Nitrogen tube in microwave ?

  1. Jun 3, 2010 #1
    I remember seeing a physicist on TV putting an argon or nitrogen sealed glass tube in a microwave and when he turned it on the tube started flashing an emitting visible light,
    So how come when i put a sealed glass jar that i glued a lexan lid on in the microwave it does not emit light , i realize that the air in the jar is a mixture of gases , there is probably something fundamental i am missing .
     
  2. jcsd
  3. Jun 4, 2010 #2
    The factor you're missing is pressure:
    http://en.wikipedia.org/wiki/Paschen's_law
     
  4. Jun 4, 2010 #3

    turbo

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    Gold Member

    The tubes are filled with low-pressure argon or neon in an otherwise evacuated tube.
     
  5. Jun 4, 2010 #4
    Thanks for the answers ,
    so if i evacuated some of the air in the tube , and reduced the pressure would it emit light .
     
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