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Question about Light

  1. Mar 5, 2007 #1
    Suppose there was a spherical red light source and that was the only thing that existed. Would your eye see a red ball surrounded by blackness, or would your whole vision be uniformly red, or would you see all red but in decreasing intensity?
     
  2. jcsd
  3. Mar 5, 2007 #2

    russ_watters

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    Staff: Mentor

    Have you ever looked at the stars at night...?
     
  4. Mar 5, 2007 #3

    HallsofIvy

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    Science Advisor

    In case you haven't- When you look at the stars at night you see bright lights surrounded by blackness. (Works best far away from city lights- spend a night in the Utah desert some time- it's awesome!)

    You would only see "all red but in decreasing intensity" if there were a cloud of something to reflect the light around the source.
     
  5. Mar 5, 2007 #4
    Maybe my question is more biological but, wouldn't light from a sphere come out in every direction and thus hit every part of your eye, assuming there was absoluely no other source of light?
     
  6. Mar 5, 2007 #5

    russ_watters

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    Yes, if your eye didn't have a lens on it to focus the light.
     
  7. Mar 5, 2007 #6
    I had no notion of a lens (I just looked it up) and didn't understand why everything isn't a blur. Thanks.
     
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