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Wavelength from collision

  1. Nov 4, 2008 #1
    Hey all,

    A physics example I'm working on to do some studying. The example is as follows:

    What is the wavelength of the scattered photon when a free electron (initially stationary) acquires maximum energy in a collision with a photon of energy 4 x 10^3 eV?

    My problem is this: it seems anything I do only deals with the photon of energy 4 x 10^3 eV. i.e. I can find the frequency using the relation E=hf and then lambda using lambda = c/f, but none of that relates to " lambda prime". Help?

    Thanks in advance.
  2. jcsd
  3. Nov 4, 2008 #2
    to add... I have a feeling that the electron acquires "maximum energy" means something, that I am not picking up...
  4. Nov 4, 2008 #3


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    Staff: Mentor

    This looks like a Compton scattering problem. Hint: In a collision that delivers the maximum possible KE to the electron, in what direction would you expect the photon to emerge (and which direction does the electron recoil)?
  5. Nov 4, 2008 #4
    got it, thanks!
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