- #1
spacetimedude
- 88
- 1
Homework Statement
Given [tex] \hat{P}_r\psi=-i\hbar\frac{1}{r}\frac{\partial}{\partial{r}}(r\psi)[/tex], show [tex]\hat{H}=\frac{1}{2m}(\hat{P}^2_r+\frac{\hat{L}^2}{r^2})[/tex]
Homework Equations
The Attempt at a Solution
The solution starts out with [tex]\hat{P}^2\psi=-\hbar^2\frac{1}{r}\frac{\partial}{\partial{r}}\frac{\partial}{\partial{r}}(r\psi)[/tex] but I am not sure why it's 1/r isntead of 1/r^2 when I square P?
Thank you