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Homework Help: Alpha particle touching Gold nucleus

  1. Jun 26, 2011 #1
    1. The problem statement, all variables and given/known data
    If the radius of the gold nucleus is 6.47 fm, and the radius of the α particle is 2.36 fm, then what is the minimum required kinetic energy for the α particle if we want the two nuclear surfaces to touch in a head-on collision?

    2. Relevant equations
    Ue=(kq1q2)/r


    3. The attempt at a solution
    so using Ue=KE
    q1=2
    q2=79

    then it should be straightforward plug and chug, however the KE this yields is very high, around 3E45 eV this cannot be right, what am I doing wrong?
     
  2. jcsd
  3. Jun 27, 2011 #2

    NascentOxygen

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    Staff: Mentor

    The alpha-particle moves from infinity to a distance of ralpha + rau femtometres from the centre of the gold nucleus.
     
  4. Jun 27, 2011 #3

    ehild

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    Homework Helper



    what is the unit of q?

    ehild
     
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