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Homework Help: Particle in a box

  1. Apr 1, 2007 #1
    1. The problem statement, all variables and given/known data

    In a region of space, a particle with zero total energy has a wave function
    [tex]\Psi (x) = Axe^{-x^2/L^2}[/tex]

    Find the potential energy U as a function of x.

    3. The attempt at a solution

    I don't understand how this particle can have zero total energy? Wouldn't this imply that the potential energy is simple 0 everywhere...
  2. jcsd
  3. Apr 1, 2007 #2
    Wait, would I have to describe the potential like we do for an infinite square well?
  4. Apr 1, 2007 #3
    Use time-independent Schrodinger eqn.

    Zero total energy means that PE=-KE.
  5. Apr 1, 2007 #4
    So with E = 0 I can say [tex]\frac{d^2\Psi}{dx^2} = -\frac{2mU}{\hbar ^2} \Psi[/tex]

    which mean I can get solutions just like in my text but I don't what I can apply as boundry conditions or how to get U in terms in x.
    Last edited: Apr 1, 2007
  6. Apr 1, 2007 #5
    Divide both sides by psi(x) to get U(x).

    psi(x) already obeys the relevant boundary conditions.
  7. Apr 1, 2007 #6
    Ah I see now :P I feel kind of stupid :\

  8. Feb 23, 2008 #7
  9. Feb 23, 2008 #8
    i would lke to b informed how to prepare a lab report on the Hall Effect hopping that i will b given an intensive help over the matter
    N.B...i did the experment of the hall effect when a moving conducter moves through a magnetic fild while two variable resistors of 8 and 16 ohms connected to it and the source and the ammeters so as to had the observation
    hopping that i will b directed sufficently
    urs faithfully......................
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