1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: 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 (+45º 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


    User Avatar
    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"
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook