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Homework Help: Concave Mirror and objects distance

  1. Mar 18, 2008 #1
    1. The problem statement, all variables and given/known data
    A concave mirror (f = 44 cm) produces an image whose distance from the mirror is one-fourth the object distance.

    (a) Determine the object distance.
    cm

    (b) Determine the (positive) image distance.
    cm



    2. Relevant equations

    1/do +1/di =1/f do=object distance and di=image distance


    3. The attempt at a solution

    Since there are two unknowns I thought I could change the equation to 1/do + 1/4do = 1/f....and solve but this wasn't turning out right? am I going about this the wrong way?
     
  2. jcsd
  3. Mar 18, 2008 #2
    Is 1/4do equal to (1/4)do or 1/(4do)? In any case, if the image distance is one-fourth the object distance, does that mean that di = 4do?
     
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