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Does thermal radiation involve ultraviolet x ray and jamma ray

  1. Mar 5, 2014 #1
    does thermal radiation involve ultraviolet x ray and jamma ray or just heat of light......
    Last edited: Mar 5, 2014
  2. jcsd
  3. Mar 5, 2014 #2
    It involves all of them. Some more than others though.

    The image below shows the amount of radiation across all wavelengths for a few different temperatures.

    As you can see, the vast majority is infra-red, and this is normally the typical 'thermal radiation' heat you talk of. Only when something gets reaaaally hot does it start to emit most of its energy as visible light.

    For reference, the sun is just less than 6000K, so a lot of its radiation is visible to the human eye.

  4. Mar 5, 2014 #3


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    There aren't any 'jamma' rays. There are 'gamma' rays (with a hard 'g')

    Unless you pledged 'Phi Slamma Jamma' in college.
  5. Mar 5, 2014 #4
    Haha. The more worrying thing is that this person is surely just spelling it how it sounds. And if they think it says 'jamma', then that must be the way their teacher is saying it to them....!
  6. Mar 6, 2014 #5
    If that's the case, how do you explain the (correct) double m? May be the j is just a typo?
  7. Mar 6, 2014 #6

    My logic was a silly and jestful wild guess in the first place, but if you'd like an explanation then I'll add that I was going on the assumption that maybe this person (or their teacher) had thought the word was pronounced 'jamma', which is definitely a possibility, considering the ways the letter 'g' can sometimes be pronounced.

    And in the pronunciation of 'jamma', it's surely only natural to spell it with a double m.
  8. Mar 6, 2014 #7


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    In English ga, go, gu are all pronounced with a hard g. ge and gi are usually pronounced with a soft g, but not always.
  9. Mar 6, 2014 #8
    Indeed! But not everybody knows this.
  10. Mar 7, 2014 #9


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    OMG Whatever you do, never try to find 'rules' for English Pron(o)unciation. English is sooo irregular, it will drive you mad.
  11. Mar 7, 2014 #10


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    It is also instructive to see the spectrum of black body radiation, given in terms of frequency rather than wavelength.
    See this YouTube video.
    Note the scale that's used here, which stretches the low frequencies and compresses the high frequencies, before trying to come to any numerical conclusion.
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