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Homework Help: Convex lens question

  1. Jun 7, 2006 #1
    I have to complete a problem about locating an image for a convex lens but I'm having trouble with it. I tried it out, but I can't complete it. Can someone help please?

    Locate the image for the convex lens below. Use any two rays to do so. Give the characteristics of the image.

    I'm having trouble particularly with describing the image. I'll attach the picture of the lens and my answer to it.

    Attached Files:

  2. jcsd
  3. Jun 8, 2006 #2
    you need to work out the focal length of the lense, try looking in an optics book.
  4. Jun 8, 2006 #3


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    Homework Helper

    Is the image real or virtual? Is it upright or inverted? How much larger is it than the object?
  5. Jun 8, 2006 #4


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    Staff: Mentor

    No, it's a graphical problem. The first diagram shows the focal points and the location of the object, so he has enough information to locate the image, which he did in the second diagram.

    All he has to do now is describe the key characteristics of the image. Usually this means saying whether it's real or virtual; upright or inverted; enlarged or reduced in size. Maybe calculate the numerical value of the magnification by measuring the sizes of the object and image.
  6. Jun 8, 2006 #5
    okay, thanks a lot guys.

    So it's real, inverted, and M>1
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