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Homework Help: Conceptual question: how do we even see objects?

  1. Aug 31, 2008 #1
    1. The problem statement, all variables and given/known data

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    3. The attempt at a solution

    In my physics class we are learning about the EM radiation/wave nature of light/wave optics / image formation by mirrors and lenses, and I had a general question that was not really discussed in the textbook.
    I understand the "technical aspects" such as understanding the equations and concepts/ how images are formed with mirrors and lenses etc, but what is exactly going on with the objects? How do we even see things in the first place?
    seems like a dumb question, but i'm not sure of the answer

    for example, suppose we have an object and a convex mirror
    for the ray diagram we would draw rays coming from the object and reflecting off the mirror, forming an image.
    are these rays coming from the object? where do these rays come from?
    is the answer that the object absorbs solar radiation but doesn't absorb all the light, then the light that isn't absorbed by the object travels to the mirror and is reflected off?

    thank you!
  2. jcsd
  3. Aug 31, 2008 #2
    As far as I can tell that is correct. The light from the sun hit's the object. The object absorbs some of the light. The rest is reflected off of it and then will hit the mirrors surface which will in turn reflect the light to your eyes...thus you see the object.
  4. Aug 31, 2008 #3


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    What you have described is absorption/reflection and is how objects project color. White reflects all the light, black then little. But of course how we actually see - process photons, perceive relationships, integrate images, structure, etc is a much more complicated organic process than appropriate for here.
  5. Aug 31, 2008 #4
    pretty much
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