Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Another Quick Couple of Infinite Well Questions

  1. Jan 28, 2007 #1


    User Avatar
    Homework Helper
    Gold Member

    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


    User Avatar
    Homework Helper
    Gold Member

    wait, just remembered....i gotta find c_n^2...
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook