# Quantum mechanics - finite square well

• Graham87
In summary, the correlation between the height in b) and energy levels height in c) and T and R is due to the factor of k, which is defined as the square root of (2m(V_0-E)/h). This factor is used in the formulas for T and R, which are T=1-R and R=|A|^2/|B|^2, respectively. When plugging in k into the R formula, the opposite answer is obtained, which may be due to incorrect use of the formula or incorrect definition of k. Further clarification is needed to fully understand the relationship between these variables.

#### Graham87

Homework Statement
In which case would you expect the reflection coefficient to largest, for a particle with energy E?

For which of the energy levels would you expect that the tansmission coefficient would be largest?
Relevant Equations
##R=\frac{|A|^2}{|B|^2}##

##T=1-R##

##k=\sqrt{\frac{2m(V_0-E)}{h}}##

##\psi(x)=Ae^{kx}+Be^{-kx}##

In a) I get that T should be largest where V_0 is least wide, because when V_0 is infinitely wide the particle would be fully reflected.
But I don't get how height in b) and energy levels height in c) correlates to T and R.

Is it because of their k? I get the opposite answer from the correct one when I plug k in the R formula. ##R=\frac{|A|^2}{|B|^2}##

##T=1-R##

##k=\sqrt{\frac{2m(V_0-E)}{h}}##

##\psi(x)=Ae^{kx}+Be^{-kx}##Thanks!

Last edited:
Graham87 said:
But I don't get how height in b) and energy levels height in c) correlates to T and R.

Is it because of their k? I get the opposite answer from the correct one when I plug k in the R formula.
You need to define what you mean by ##k##. And what formulas are you using for ##T## and ##R##?

Graham87
vela said:
You need to define what you mean by ##k##. And what formulas are you using for ##T## and ##R##?
Done!