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Homework Help: Pinhole Camera Equations

  1. Jul 21, 2008 #1
    1. The problem statement, all variables and given/known data
    It's not a specific problem, persay......

    I'm working on a science lab and I'm supposed to be deriving the height of an image created by a pinhole camera. Since I'm in a condensed Physics course, we are expected to figure out formulas on our own. I keep finding this formula:

    (height of image) / (height of object) = ( - distance of image) / (distance of object)

    And since Di = Do, it should work.

    The problem is, that formula is associated with curved mirror questions...a pinhole camera is something else. Will that formula work? It's the only one I can find to determine the height of image from distance of object and height of object.

    I really need help with this, I'm completely stuck and I have no idea what's right and what isn't.

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Jul 21, 2008 #2


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    Homework Helper

    Draw a diagram. Include the light ray from the top and bottom and how it projects onto the surface. Geometry should tell you what the relationship is between the height of the object, the distance from the pinhole, the distance to the surface and the height of your image there.
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