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Homework Help: Focal Length

  1. Apr 23, 2010 #1
    1. The problem statement, all variables and given/known data

    a) What is the focal length of the eye-lens system when viewing an object at infinity? Assume that the lens-retina distance is 1.8cm.
    b) What is the focal length of the eye-lens system when viewing an object 35cm from the eye? Assume that the lens-retina distance is 1.8cm .


    2. Relevant equations



    3. The attempt at a solution

    I assumed that for part A that 1/inf went to zero but that answer was wrong. I'm not sure How to calculate this. Please help if you can.
     
  2. jcsd
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