How many points of zero probability in a finite well?

[L_landau]

Homework Statement

An electron is trapped in a finite potential well that is deep enough to allow the electron to exist in a state with n=4. How many points of (a) zero probability and (b) maximum probability does its matter wave have within the well?

Homework Equations

For infinite potential well there are nodes at the walls and λ = 2L/n as in the case of a string with two clamps.
In this case there are n+1 nodes and n antinodes.

The Attempt at a Solution

I read in the textbook that the analogy between clamped strings and quantization fails for the finite potential well because the wavefunction probability is non-zero in the potential. Judging by the graphic included, I would say that there are (a) n-1 nodes and (b) n antinodes for the finite potential well case. Is this right?

 

[TSny]

Judging by the graphic included, I would say that there are (a) n-1 nodes and (b) n antinodes for the finite potential well case. Is this right?

Yes, that's right.