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When bulb light passes through a prism

  1. Nov 12, 2005 #1
    When bulb light passes through a prism why doesn't it give different colors?

    From what I understood about light bulbs, it should give red, orange and yellow as descrete lines. Why doesn't this happens and it goes out of the prism almost as it enters?

  2. jcsd
  3. Nov 12, 2005 #2


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    I've never heard of that. Maybe the light source is just overpowering (washing out) the separate colour bands. Try shrouding it so it all goes through the prism.
  4. Nov 12, 2005 #3
    I assume you have a flourescent light "bulb"? Incandescent light bulbs don't emit in discrete lines, but continuous spectra, just like the sun.

    Are you projecting onto a white surface? What exactly do you see?
  5. Nov 12, 2005 #4


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    Are you passing the light through a slit before it reaches the prism, or are you just holding the prism up to the light from a light bulb?
  6. Nov 12, 2005 #5
    Oh thanks... I've just noticed this piont. Because in my mind I was comparing it with the case of Helium spectrum :redface:


    I'm confused because the light came out of the prism almost as a line. Ok.. maybe because it doesn't have many colors so the spectrum is not very wide and that make it looks almost almost as a line. Am I right?
    I need to try it again..

    Thanks everyone
    Last edited: Nov 12, 2005
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