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Light sources

  1. Sep 20, 2005 #1
    I wonder... If I were in a room with no windows, and completely isolated. The room had red, yellow, orange, and blue objects in it. Now, there was NO light source. So, as soon as the door closes, it's completely dark. The only light source is light that emits red light. Okay, would the red objects be the only objects ulliminated? Because, the only light they reflect is red, everything else absorbs red.
    If that's true, how does those red-coted light bulbs work?
  2. jcsd
  3. Sep 20, 2005 #2

    Claude Bile

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    Science Advisor

    Very few objects that do not posess a special coating of some sort have distinct cut-offs in terms of their reflection spectra. By this I mean that even blue objects, for example will reflect some red light. Blue objects look blue because they reflect substantially more blue light than red light.

    If you illuminate an object (of any colour) with red light only, the object will look red, because there is no green or blue light competing with the receptors in your eyes.

  4. Sep 20, 2005 #3
    Hmmm...Okay, thanks.
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