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: Nuclear reaction cross section

  1. Sep 15, 2008 #1
    Suppose we consider a beam of neutrons incident upon a thin target with an intensity of 10^12 neutrons/(cm^2.s). Suppose further that the total cross section for the nuclei in this target is 4 b. Using this information, determine how long one would have to wait, on the average, for a given nucleus in the target to suffer a neutron interaction.

    The way i approached this is to get a rate from Intensity*cross section = rate
    this gives

    10^12 neutrons/(cm^2 sec) * 4.0 × 10^-24 cm^2 = 4 × 10-12 s^-1

    Then taking 1/rate should give the length of time...but this gives an extraordinarily long time of course which leads me to believe something is wrong?
    how should this be approached
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted