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: Two diffraction gratings one on top of the other

  1. Sep 8, 2012 #1
    1. The problem statement, all variables and given/known data

    Two diffraction gratings are stuck together, both with vertically aligned slits. Grating A has S1 slits and B has S2 slits.
    What is the new equivalent grating that is the product of two of the diffraction gratings above?


    2. Relevant equations

    a. N* = 1/d

    3. The attempt at a solution

    Assuming that there are ajacent slits in both - I tried to think of a way that it will make sense.
    If s1>s2 , s1 should be a multiple of s2, but I couldn't figure out a way to come to the new grating equivalent.
  2. jcsd
  3. Sep 9, 2012 #2


    User Avatar
    Homework Helper
    Gold Member
    2017 Award

    Suppose d1 and d2 are the distances between consecutive slits for the gratings. What if the ratio of d2/d1 happens to reduce to 3/2? What would be the answer to the question? How about if the ratio reduces to 5/3?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook