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Homework Help: Speed of electrons

  1. May 7, 2008 #1
    [SOLVED] speed of electrons

    1. The problem statement, all variables and given/known data

    In the Bohr model of the hydrogen atom, an electron circles a proton at a radius of 5.3e-11 m. How fast must the electron be moving if the centripetal acceleration is to be supplied by Coulombic attraction?

    2. Relevant equations

    L=n(h/2pi) where h is plancks constant and n is an integer

    L=rmv


    3. The attempt at a solution

    n(h/2pi)=rmv

    v=n(h/2pi)/(rm)

    v= n(6.63e-34/2pi)/(5.3e-4)(9.11e-31)

    v= 0.218n m/s

    Now that velocity seems way to small for a speed of an electron....

    Any help is appreciated! Thanks!
     
  2. jcsd
  3. May 7, 2008 #2

    hage567

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    Homework Helper

    Why is this a 4 instead of an 11?
     
  4. May 7, 2008 #3
    Thank you....My 11 looked like a 4 in my notes...simple mistakes can kill you! haha

    I got a very large velocity now so the answer makes more sense.
     
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