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mlee
Dec5-04, 11:28 AM
hey who can help me with this physics problem?

A particle of mass m is in the state:
Ψ (x, t) = Aexp[-a(sqrt (mx^2) / h)-i (at / sqrt(m )) ]
where A and a are positive real constants.
a) Determine A.
b) What is the frequency ƒ associated with the wave function of this particle?
Explain your reasoning.
c) For what potential energy function U(x), does Ψ satisfy the Schrödinger
equation?
d) If we use the interpretation of [Ψ(x)]^2 dx as the probability that a particle of
mass m can be found in a region of width dx around the position x,
calculate the expected value (average value) of the position x.


Many thanx

Palindrom
Dec5-04, 12:20 PM
A. Normalize it.
\int_{-\infty}^{+\infty} \psi^*(x) \psi(x) dx =1
B. Please don't make me do that. I have my own. It's probably just hard work.
C. Differentiate it and place it in Shroedinger's equation. You'll get the potential.
D. By definition:
<x>=\int \psi^*(x) x \psi(x)\,dx

Nylex
Dec5-04, 12:23 PM
C. Derive it and place it in Shroedinger's equation. You'll get the potential.


By "derive", you mean "differentiate" or "take the derivative", right? Those things don't mean the same as "derive".

Palindrom
Dec5-04, 12:36 PM
By "derive", you mean "differentiate" or "take the derivative", right? Those things don't mean the same as "derive".
That's what I meant. You'll have to forgive me, I'm not used to saying it in English.

dextercioby
Dec5-04, 12:49 PM
A. Normalize it.
\int_{a}^{b} \psi dx =1
For a and b being - and + infinity.
B. Please don't make me do that. I have my own. It's probably just hard work.
C. Differentiate it and place it in Shroedinger's equation. You'll get the potential.
D. By definition:
<x>=\int \psi^*(x) x \psi(x)\,dx

1.Your edited your post and now it's "differentiate".
2.The first formula is incorrect;it has something missing:
\int_{-\infty}^{+\infty} \psi^*(x) \psi(x) dx =1
The rest is correct and i agree with you.

Palindrom
Dec5-04, 12:52 PM
1.Your edited your post and now it's "differentiate".
2.The first formula is incorrect;it has something missing:
\int_{-\infty}^{+\infty} \psi^*(x) \psi(x) dx =1
The rest is correct and i agree with you.
Thanks for the correction, I edited.