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Homework Help: Acceleration of an electron held at 1m from the nucleus of an Uranium atom.

  1. May 7, 2012 #1
    1. The problem statement, all variables and given/known data

    An electron is held fixed at a distance of 1 m from the nucleus of a uranium atom (Z = 92). If the electron is then released, what is the magnitude of its initial acceleration?


    2. Relevant equations

    I am not sure which kinematic equation that I should use.

    3. The attempt at a solution

    This is the only problem on my physics final review that I do not know how to do. I know that the answer is 23,300 m/s^2, but I do not know how to get this answer. I would really love it if someone could explain how to solve this to me.
     
  2. jcsd
  3. May 7, 2012 #2

    Doc Al

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    Staff: Mentor

    This is a dynamics problem, not a kinematics one. Hint: What force acts on the electron?
     
  4. May 7, 2012 #3
    I was thinking the strong nuclear force, but I believe at 1m it is too far for that to have an effect. The only other thing I could think of would be gravity?
     
  5. May 7, 2012 #4

    Doc Al

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    Staff: Mentor

    Neither of those forces would be significant. What other force acts?
     
  6. May 7, 2012 #5
    The only other thing I could think of would be Coulomb's law. This is the only problem out of 100 that I just have no clue about. I keep rereading my notes but can't seem to find out what I'm missing on.

    Thanks for the help though, I appreciate you trying to lead me to the answer.
     
  7. May 7, 2012 #6

    Doc Al

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    Staff: Mentor

    That's the one.

    The positively charged nucleus attracts the electron with an electrical force given by Coulomb's law. Figure out that force.
     
  8. May 7, 2012 #7
    Thanks! Here, it was an incredibly easy problem.
     
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