I was recently given a problem that asked me to show that the classical velocity of a particle is given by:(adsbygoogle = window.adsbygoogle || []).push({});

[tex] v = \frac{d \langle x\rangle}{dt} = \frac{1}{m} \langle({\bf p}-q{\bf A})\rangle[/tex]

The expectation value of the time derivative of x is given by:

[tex]\langle v\rangle = \int{\Psi ^{*} (x \frac{d}{dt}) \Psi[/tex]

So then I just work this out, and what do I do after that? How do I get from here to the form the problem is asking for?

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# Homework Help: Quantum mechanics question.

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