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Homework Help: Another Quick Couple of Infinite Well Questions

  1. Jan 28, 2007 #1


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    1. The problem statement, all variables and given/known data
    Problem 1. If I had a wavefunction: [tex] \Psi(x,0) = A(\psi_1(x) + \psi_2(x))[/tex]

    What is the probability of getting E1 or E2 as your energy?

    Problem 2 You have a wavefunction:

    [tex] \Psi(x,0) = Ax; 0<= x <= a/2 ; A(a-x); a/2<= x <= a [/tex]
    What is the probability that an energy measurement would yield E1.

    2. Relevant equations
    Given Up above

    3. The attempt at a solution
    For problem 1, i feel the probabilities should be 1/2 for each of them, but this seems too easy. I also normalized and found Psi(x,t), A = 1/sqrt(2)

    For problem 2 I'm completely lost
    There are an infinite amount of energy levels so shouldnt the probability be 0, but then this doesn't make any sense. I feel I'm missing something. Are the probabilities not that easy?
  2. jcsd
  3. Jan 28, 2007 #2


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    wait, just remembered....i gotta find c_n^2...
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