Linear Harmonic Oscilator - QM

Brewer
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Just a quickie:

A particle is in the first excited Eigenstate of energy E corresponding to the one dimensional potential V(x) = \frac{Kx^2}{2}. Draw the wavefunction of this state, marking where the particles KE is negative.

Now my question.

The first excited state will be n=1 correct? The first excited state is not the ground state under a different name is it?

So if it is n=1, then the wavefunction will look like a sin wave? And the KE will be negative on the left hand side of the sin wave (i.e. where a graph of sin(x) will be negative.)?

Ta guys.
 
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I think you'll have to do more than just guess. But here's a hint. The first excited state is indeed not the ground state. It has one node in the wavefunction. The ground state has zero.
 
Well I've drawn the right form of the wavefunction at least. Whether or not I've correctly identified where the KE is negative I don't know. Back to the textbook I go!
 
Brewer said:
Back to the textbook I go!

Great idea! Once you have the wavefunctions remember KE is an operator on wavefunctions.
 
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