# Graph of a wave function and how to work out velocity from it.

1. Nov 27, 2007

### Rich667

1. The problem statement, all variables and given/known data
Open Question 2.bmp

2. Relevant equations

3. The attempt at a solution

I really struggled with this one, my answer is nothing more than an incomplete educated guess.

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2. Nov 27, 2007

### robphy

In terms of the wave-function... graphically (or visually) speaking.... what does "velocity" mean?

3. Nov 27, 2007

### Rich667

"Velocity" means the speed the object (or in this case wave) is moving at in a certain direction.

But I don't know how to obtain the value of Velocity from the graph (that I still do not know how to draw).

4. Nov 27, 2007

### robphy

At some time t=T, consider a snapshot of the graph. Focus on particular point (a bump, if wish) located at x=X on the graph. So, that feature has height H=g( 0.5X - 3T ). As T increases, what happens to that feature [keeping that height the same (which means keeping constant (0.5X - 3T) ]?

It might help to redraw your function at various times t (as suggested in your assignment).