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I Ionising radiation and light bulbs

  1. Mar 21, 2016 #1
    Can ionising radiation (gamma rays) diffuse incandescent light bulb filled with inert gas ?
     
  2. jcsd
  3. Mar 21, 2016 #2
    what is ionisation energy for inert gases?
    if somebody can provide it through gamma rays /or some thermal motion it is possible to ionise say those gases-but how it will diffuse the light coming from the lamp?
    in lab spectrometer one gets the neon lines from say sodium vapor lamps.
     
  4. Mar 21, 2016 #3
    is it possible to damage light bulb'S tungsten filament by exposing to ionising radiation?
     
  5. Mar 21, 2016 #4
    again its a question related to energy transfer from radiation to the states of atoms in the filament -
    One info i can share the Tungston filament bulbs used as Diodes ( used in olden days) used to be blackened due to sputtering of the metal ions which later deposited on the inner side of the bulb- so high temp also leads to ionization.
     
  6. Mar 21, 2016 #5
    thanks for ur reply
    can ionizing radiation ionize argon, krypton & xenon gases ?
    if so, what reaction will happen between these ionised gas and hot tungsten filament ?
     
  7. Mar 21, 2016 #6
    can ionising radiation (gamma) ionize the inert gas filled in incandescent light bulb, and make tungsten to react with inert gas ? can ionizing radiation turn off a small flash light bulb if placed near a ionizing radiation source ? like ir 192 or other isotopes having high energy gamma emission ?
     
  8. Mar 21, 2016 #7

    mfb

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    What does "diffuse a light bulb" mean?
    Sufficient flux will damage the filament and weaken the material, but I would not expect relevant damage unless you put it in a nuclear reactor or in an LHC experiment.
    Sure, that's why it is called ionizing radiation. The gases will quickly capture electrons again, from the environment or from a surface, without a chemical reaction. There are just a few noble gas compounds, and they all require cold temperatures to be stable.
    I don't see how.
     
  9. Mar 21, 2016 #8
    the task is to damage (filament) or turn off a small incandescent light bulb in flash light (2.4 v flash light bulb) without touching the flashlight.
    dont say to try EMP devices please. i already tried it using massive 20KV EMP device, :-)
     
    Last edited by a moderator: Mar 21, 2016
  10. Mar 21, 2016 #9

    ZapperZ

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    Your question is verging on being silly.

    If you read mfb's reply, you would already have the answer! But the question is, to what extent is this exposure?! This is something you never indicated.

    Here's a summary:

    1. If you expose the tungsten wire to a "high enough" gamma radiation for "long enough" period of time, sure, it will suffer structural/material damage! This should answer your question already.

    2. Is this likely under "normal" circumstances? No!

    3. Is this likely to change the nature of the light being given off by tungsten? No! It will require a substantial amount of damage to the entire structure of tungsten to produce a NOTICEABLE change in the characteristics of light from such a source. After all, I can dope tungsten different ways, and you still won't be able to tell any difference from one light bulb to another.

    4. Unless you are willing to make a QUANTITATIVE description of the nature of the exposure, your question will remain utterly vague.

    Zz.
     
    Last edited by a moderator: Mar 21, 2016
  11. Mar 21, 2016 #10
    dear zapper,

    how do you dope tungsten filament of light bulb ?
     
    Last edited by a moderator: Mar 21, 2016
  12. Mar 21, 2016 #11

    ZapperZ

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    During the fabrication of the wire! Do you think that tungsten wire is PURE, 100% tungsten?

    Zz.
     
    Last edited by a moderator: Mar 21, 2016
  13. Mar 21, 2016 #12
    i dont think its 100% pure, will you please tell me how filament is made.
     
    Last edited by a moderator: Mar 21, 2016
  14. Mar 21, 2016 #13

    ZapperZ

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  15. Mar 21, 2016 #14
    light bulb is filled with argon and nitrogen mixture.
    tungsten reacts with normal gases at higher temperatures. but why it is not reacting with nitrogen to form tungsten nitride ?
    at higher temperature 2500 degrees centigrade when we expose the gases inside the bulb to ionizing radiation, will nitrogen react with hot tungsten thus leading to form uneven cross section in the filament which creates a point generating much heat sufficient to tungsten melting ?
     
  16. Mar 21, 2016 #15

    ZapperZ

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    You are all over the place now. Is this still related to the original topic? You never once acknowledged if any of your questions have been answered.

    You are now asking about specific reaction and growth condition. This is now a different topic and is more suitable for Chemistry or Material Science.

    Zz.
     
  17. Mar 21, 2016 #16
    when we microwave a light bulb in oven or place a bulb near magnetron of microwave oven the blue plasma forms inside the bulb, is this because of ionization of gas inside the bulb by microwaves ? after that bulb glows brightly for one or two minutes and it will burn (filament). what happens when microwaves strike gases inside the bulb ? will microwaves heats up gases in the bulb ?
     
  18. Mar 21, 2016 #17

    mfb

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    Explosives nearby are technically not touching it as well... but to turn it off, simply disconnect the power cord.

    Stop posting more and more unrelated questions, please, before the previous ones are solved. That does not help anyone.
     
  19. Mar 21, 2016 #18

    berkeman

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    Where did you get this task? Is this for schoolwork?
     
  20. Mar 21, 2016 #19
    may be u think im a fool if i say. actually i will get 100 million indian rupees if i do that.
     
  21. Mar 21, 2016 #20

    berkeman

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    You have been told repeatedly that text speak like "u" is not allowed here. Please do not do it again.
     
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