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Homework Help: Single Slit Exp.

  1. Feb 2, 2009 #1
    A single slit with width 819 nm is illuminated with light of wavelength 405 nm. How many
    minima occur in the angular range from theta = 0 to theta = ±19deg?

    I have an exam tomm please help me out with some problems.

    actually, i hv the answer but i don't know how to derive it!!!
  2. jcsd
  3. Feb 2, 2009 #2
    i just googled 4 keywords and got the formula, try it! :)
  4. Feb 2, 2009 #3
    Please Help me though!!!!
  5. Feb 3, 2009 #4
    tan(theta) = m * Wavelength/SlitWidth

    You know all the values except m.
    m is the number of minima (it's an integer obviously).

    Be careful about the angle, its a plus-minus.
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