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How do we see things that don't create photons?

  1. Aug 4, 2006 #1
    How do we see things? I know we see things when photons are created by the object or other photons. But how do we see things that don't create photons?

    For example: if you look at a red piece of paper in a room that is lit with a regular lightbult. The paper does not create photons so what's happening?
  2. jcsd
  3. Aug 4, 2006 #2

    Doc Al

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    Staff: Mentor

    The paper reflects the light from the bulb.
  4. Aug 6, 2006 #3

    Claude Bile

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    Objects don't need to emit light to be visible, they only need to reflect or scatter light coming from somewhere else.

  5. Aug 6, 2006 #4


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    Why the piece of paper appears red is because it is reflecting the "red photons" more than it reflects other photons (which it ends up absorbing). So, it's mostly the red photons that make it to your eyes.
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