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: 1-D wave interference

  1. Mar 18, 2009 #1
    1. The problem statement, all variables and given/known data
    Monochromatic light of wavelength [tex]\lambda[/tex] = 400 nm enters at A. It impinges on a ‘half-silvered mirror’ B, which directs some of the light to mirror C, while passing the rest to mirror D. Some of the reflected light from mirror C passes back through the half-silvered mirror, where it combines with reflected light from D, arriving at the detector. Mirror C is attached to a micrometer, so that it can be moved to change the path length B − C − B.
    If mirror C is moved through 10 microns (1 micron is 10−6 m), how many maxima will be
    observed at the detector? Assume that the intensity at D is intially a minimum.

    2. Relevant equations

    3. The attempt at a solution
    I'm actually not sure how to approach this to begin with, so any advice is appreciated. I've also attached a copy of the diagram. I'm thinking this might have something to do with the path length being x1 and x2

    Attached Files:

  2. jcsd
  3. Mar 19, 2009 #2


    User Avatar
    Science Advisor
    Homework Helper

    Hi XJellieBX! :smile:

    If mirror C is moved through 10−6 m, how much longer does that make the path?

    So how many wavelengths is that? And how many maxima will go past?
  4. Mar 19, 2009 #3
    So if I find how many wavelengths that is, which i did find, i can figure out the number of maxima. I'm just not too sure if that is all this question is asking for, but thank you nevertheless =)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook