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Homework Help: Question based on Lenses -O level/gcse

  1. Mar 20, 2017 #1
    • New poster has been reminded to post schoolwork-type questions in the HH fourms and to use the Template
    Hey can anyone explain this question to me?

    Attached Files:

  2. jcsd
  3. Mar 20, 2017 #2

    Andy Resnick

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    Have you tried applying the thin lens equation? Hint: what's the definition of magnification?
  4. Mar 20, 2017 #3
    yeaah i tried using magnification=image/object ratio thing. But idk why in the solution they have taken the length of image as 50. I agree with taking 20 as the length of object but i dont get the taking 50 as the length of image.
  5. Mar 22, 2017 #4


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    Homework Helper

    The location of the image is deterimined by drawing three special light rays from the object through the lens.
    How should such rays be drawn?
    Have you tried constructing such a drawing by say using a scale of 1 cm in the drawing is 2 cm in real life?
    Last edited: Mar 23, 2017
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