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Homework Help: Diverging lens, calculating image location

  1. Apr 11, 2010 #1
    1. The problem statement, all variables and given/known data

    Diverging lens with focus of 2 meters. The object is 3.66 meters away from the lens. Find the exact image location.

    2. Relevant equations

    1/object + 1/image = 1/f

    3. The attempt at a solution

    I plugged in the numbers with a negative value for the focal length but I keep getting a negative value (-1.29 m) for my image location. However, when I do the ray diagram (which I'm confident is correct) I find that the image should be in front of the lens. Any explanations?
  2. jcsd
  3. Apr 11, 2010 #2
    The usual sign convention for thin lenses is such that the image distance is negative if the image is in front of the lens.
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