Expectation value of P for an infinite-square well

Thread starter jmm5872
Start date Mar 6, 2012
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Expectation Expectation value Value

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To find the expectation value of momentum for an infinite-square well at time t = 0, the initial wavefunction ψ(x,0) can be used directly. The formula = -ih∫ψ*(x,0)(∂/∂x)ψ(x,0)dx is applicable without needing to calculate ψ(x,t). This approach simplifies the process by allowing the use of the initial wavefunction. The discussion confirms that the use of the initial wavefunction is valid for calculating . Understanding this method is crucial for further studies in quantum mechanics.

Mar 6, 2012

jmm5872

I just have a simple question to get me started. If I am given an initial value wavefunction ψ(x,0) and I am asked to find at t = 0 can I use this:

 = -ih∫ψ*(x,0)\frac{∂}{∂x}ψ(x,0)dx

or do I need to find ψ(x,t) before I find ?

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Mar 7, 2012

bloby

No you are right (h bar)

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