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Incandescent lamp

  1. Nov 6, 2004 #1
    What color of light would be observed if white light from an incandescent lamp were passed first through a red filter and then through a green filter.
  2. jcsd
  3. Nov 6, 2004 #2


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    We can explain this phenomenon with "complementary colors". Red and green are complementary colors to each other (if I'm not wrong), so at the end I expect that darkness will result, since red filter doesn't pass red light and green light remains, and this is stopped by green filter, so no light can pass unless there is a deviation from ideality.
  4. Nov 7, 2004 #3
    so the colors that would show up would be all the colors from an rainbow except for red and green?
  5. Nov 8, 2004 #4
    please help?
  6. Nov 8, 2004 #5
    red filters pass red light. green filters pass green light.
    depending on how selective your filters are, the red filter will remove any light that isn't red. Since the green filter removes anything that isn't green, the leftover red light will be removed by the green filter and you will end up with dark.
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