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Homework Help: Converging lens

  1. Apr 25, 2006 #1
    A converging lens has a focal length of 25cm. A 1.00cm tall object is placed 15.0cm in front of the lens. Find the image location and size, and describe it. Draw a ray diagram.

    Ok so I get 1/p + 1/q = 1/f rearranged for q=pf/p-f which equals -37.5, so the object is 37.5cm behind the lens. and then m=-q/p=2.50cm. The h'=mh(i)=2.50*1.00=2.50cm tall. This all works out

    BUT the ray diagram doesnt make the image at 37.5cm behind the lens. Some one help please!
  2. jcsd
  3. Apr 26, 2006 #2


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    Did you learned the sign conventions? what is the sign of the object distance?
  4. Apr 26, 2006 #3

    Andrew Mason

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