Why Doesn't My Homemade Nitrogen Tube Light Up in the Microwave?

AI Thread Summary
Homemade nitrogen tubes do not emit light in a microwave due to the pressure differences compared to commercially prepared tubes. The original tubes contain low-pressure gases like argon or neon, which allow for electrical discharge and visible light emission. In contrast, a sealed jar filled with a mixture of gases at normal atmospheric pressure lacks the conditions necessary for this phenomenon. Reducing the pressure in the homemade setup could potentially lead to light emission. Understanding Paschen's law is crucial in this context, as it explains the relationship between pressure and electrical discharge.
cragar
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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 .
 
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cragar said:
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 .

The factor you're missing is pressure:
http://en.wikipedia.org/wiki/Paschen's_law
 
The tubes are filled with low-pressure argon or neon in an otherwise evacuated tube.
 
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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