Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Propagation of uncertainty from wavenumber to wavelength

  1. Mar 13, 2014 #1
    Hi,

    This is just a quick question. If wavenumber is a variable with some standard deviation Δk, how do I propagate this spread when converting from wavenumber to wavelength? Is it just 2π/Δk or is it more complex than that?

    Thanks
     
  2. jcsd
  3. Mar 13, 2014 #2

    DrClaude

    User Avatar

    Staff: Mentor

    Its more complex than that! Think about it: with what you wrote, the worse your wavenumber measuring instrument, the better your knowledge of the wavelength?

    Check out:
    http://www.rit.edu/~w-uphysi/uncertainties/Uncertaintiespart2.html#muldiv [Broken]

    You can also get the same desult from a simple derivative:
    $$
    \frac{d \lambda}{d k} = -\frac{2 \pi}{k^2} \Rightarrow \Delta \lambda = \frac{2\pi}{k^2} \Delta k
    $$
     
    Last edited by a moderator: May 6, 2017
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Propagation of uncertainty from wavenumber to wavelength
Loading...