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OPTICS - Final tomorrow - Practice test help

  1. Dec 13, 2007 #1
    1. The problem statement, all variables and given/known data


    2. Relevant equations

    3. The attempt at a solution

    (3) I haven't been able to start this one at all.

    (6) I got part a (+45ยบ P-state). I tried to do b and I got [1+i, -i+1] which isn't a polarization state, so I'm not sure what to do with c or if there is some way I can simplify it.

    (7) Once again, I got part a. It's of the form E=[tex]E_{0}[/tex][[tex]\widehat{i}[/tex]cos(kz-wt)+[tex]\widehat{j}[/tex]sin(kz-wt)]
    Does the cosine term drop out from the initial conditions?
    For b, I'm not sure how to get the magnetic field equation. I know [tex]\overline{B}[/tex]=([tex]\overline{K}[/tex][tex]\times[/tex][tex]\overline{E}[/tex])/[tex]\omega[/tex]
    But, I'm not sure how that helps me

    Any help would be greatly appreciated!
  2. jcsd
  3. Dec 13, 2007 #2


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    Science Advisor
    Homework Helper

    3, sounds like it is describing a kepler telescope - a common design for a beam expander.
    The two positive lenses are separated by the sum of their focal lengths.
    The magnification is the ratio of the focal lengths.
    A simple sketch shows you how it works.
  4. Dec 13, 2007 #3
    What school do you go to, that paper and font, its exactly the same, is there some standard I don't know about?
  5. Dec 13, 2007 #4
    And apparently, if you only have 3 characters in a message, it's "too short"
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