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Homework Help: Problem relating to the Heisenberg's Principle

  1. Mar 25, 2010 #1
    1. The problem statement, all variables and given/known data
    An electron is placed in a box about the size of an atom that is about 1*10^-10m. What is the velocity of the electron?


    2. Relevant equations
    Heisenberg's equation
    xp=h/2pi
    xmv=h/2pi
    v=h/2pi*x*m
    where x=1*10^-10m
    m=9.1*10^-31kg
    h=planck's cosntant


    3. The attempt at a solution

    Answer is 7.29*10^6
     
  2. jcsd
  3. Mar 25, 2010 #2
    Was this REALLY the question? The uncertainty principle states that:

    [tex] \Delta x \Delta p \geq \frac {h} { 4 \pi} [/tex]

    NOT

    [tex] x p = \frac {h} { 4 \pi} [/tex]


    (I don't know how to do the reduced planck's constant in Latex)
     
  4. Mar 27, 2010 #3
    So it's 4pi not 2pi? Actually the answer I'm getting is different from that which is given at the end of my physics book.
    And while solving the problem, doesn't it become [tex]\Delta[/tex]x[tex]\Delta[/tex]p=h/4pi?
     
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