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Homework Help: Light problem

  1. Apr 3, 2005 #1
    The answer to the attachment is 6.04 cm. But the intensity should be zero when the difference in path length is half a wavelength.

    2sqrt(2)x - 2x = 2.5cm

    x = 3.02 cm. However, how come the answer is 6.04cm in stead? Can some one please explain this to me thoroughly? Thanks in advance.

    Attached Files:

  2. jcsd
  3. Apr 5, 2005 #2
    can any one explain this? thanks...
  4. Apr 7, 2005 #3


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    Science Advisor
    Homework Helper

    The overall phase change due to reflection off the mirrors is 180, thus the path difference needs to be the wavelenth, not 1/2.
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