Part 2:

We'll give the wave packet an initial "kick" of momentum .

We calculate the coefficients as before:

Question: Explain why the magnitudes of the coefficients peak where they do?
(Hint: using the eigenenergy , calculate a charactaristic momentum associated with this state)

Now the particle bounces from wall to wall. We are plotting the motion over a much shorter time span than in Part 1. The momentum is so much larger than the uncertainty in momentum () that it barely spreads at all during the time it takes to traverse the well. Notice the interference of the reflected and incoming parts of the wave packet near the walls.

Here's one with smaller momentum