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!

Physics Particle Decay Question (Cons. of Momentum?)

  1. Oct 20, 2013 #1
    Physics Particle Decay Question (Cons. of Momentum??)

    1. The problem statement, all variables and given/known data
    An isotope of Polonium 210Po with mass 3.49x10^-25 kg can decay into an alpha-particle(He Nucleus) with mass of 6.64x10^-27 kg and an isotope of lead 206Pb with a mass of 3.42x10^-25. If the polonium decays at rest. and the final decay products have a total KE of 8.65x10^-13 J, what are the speeds of the He and Pb nuclei?

    2. Relevant equations

    (m1+m2)Vo = m1v1 + m2v2

    3. The attempt at a solution

    My first thought was to plug in what was given but then I get stuck...

    (Po)(0) = (He)(V_He) + (Pb)(V_Pb)

    That gets me nowhere.

    It's multiple choice

    A. 0.17 m
    B. 0.15 m
    C. 0.08 m
    D. 0.03 m
    E. 0.00 m

    I wish I could show more work, I just dont know where to go with it at all
  2. jcsd
  3. Oct 21, 2013 #2

    Simon Bridge

    User Avatar
    Science Advisor
    Homework Helper

    All conservation of momentum problems have the same pattern.

    step 1. sketch the situation "before" ... in this case you have a Po nucleus.
    ... draw on the momentum arrow and label it ... in this case, what is the initial momentum?

    step 2. sketch the situation "after" ... in this case you have two particles.
    ... which directions to they head off in (compared to each other)?
    ... draw the momentum arrows and label them. Leave variable names for anything you don't know.

    Is there a relationship between kinetic energy and momentum you can exploit?

    Step 3. total momentum before = total momentum after.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted

Similar Discussions: Physics Particle Decay Question (Cons. of Momentum?)
  1. Cons of momentum (Replies: 1)