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Homework Help: Point Source HELP

  1. Mar 30, 2008 #1
    Point Source...HELP!!!

    1. The problem statement, all variables and given/known data
    A point source of light illuminates an aperture 2.3 m away. A 10.2-cm-wide bright patch of light appears on a screen 1.02 m behind the aperture. How wide is the aperture?

    2. Relevant equations

    3. The attempt at a solution
    This looks like a geometry problem but I am not seeing it??
  2. jcsd
  3. Mar 31, 2008 #2


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    Science Advisor
    Homework Helper

    I have included a drawing of the situation in the attachment.
    You can use the blue triangle to find the angle [itex]\alpha[/itex].
    Then use standard trigonometry to find the answer (which is the length of one of the sides of the red triangle).

    Attached Files:

  4. Mar 31, 2008 #3
    wow thank you very much!!
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