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: Polarization Reflection question

  1. Apr 26, 2006 #1
    A thin film of ethyl alcohol (n=1.36) is spread on a flat glass plate and illuminated with white light. When illuminated and viewed from directly above, it shows a coloured pattern in reflection. If the only visible light reflected by a certain region of the film is yellow (lambda=560nm), how thick is the film there? Justify (assume visible spectrum is 400-7800nm)


    I have no idea where/how to start and what it involves.

    I have a feeling it invovles Huygen's Principle and Polarization by Reflection.
  2. jcsd
  3. Apr 26, 2006 #2


    User Avatar

    Staff: Mentor

    What thicknesses of ethyl alcohol will result in the yellow light reflected off the top surface and the yellow light reflecting off the alcohol-glass surface being in phase as they head back up to the observer?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook