Finding V(x) of a given wave function?

Rumor
Messages
11
Reaction score
0

Homework Statement



"A wave function is given by Aexp[(-x2)/(2L2)] with an energy of E = h-bar2/2mL2. Assuming this is a solution to the time-independent Schroedinger equation,
a) What is V(x)? Make an accurate sketch of V vs. x with labeled axes
b) What sort of classical potential has this form?


Homework Equations



The Schroedinger time-independent equation: -(h-bar2/2m) * d2Psi/dx2 + V * Psi = E * Psi


The Attempt at a Solution



I know that to solve this problem, I have to integrate the original Psi function twice in order to plug it into the Schroedinger equation. Or normalize it, in order to plug it into the equation. E also has to be determined, but I'm not sure how to go about that or what value of n to use. Basically, my biggest problem is my lack of ability to successfully integrate the psi equation and knowing how to go about figuring out E. Could someone help me, please?
 
Physics news on Phys.org
The Schroedinger equation is a differential equation, you will need to differentiate \Psi twice, not integrate it. It is not necessary to normalize the wavefunction to solve this problem. Also, the energy of the state described by \Psi has been given to you in the problem.
 
Ah, right! Wow, I've been working on physics problem long enough that I'm starting to mix them. But anyway, after differentiating the psi function twice and plugging it back into the Schroedinger equation, am I correct in thinking that that's all to be done? Aside from simplifying and everything.
 
Yes, it's mostly an algebra problem at its heart.
 
Awesome. Thanks for settin' me straight.
 
Hi, I had an exam and I completely messed up a problem. Especially one part which was necessary for the rest of the problem. Basically, I have a wormhole metric: $$(ds)^2 = -(dt)^2 + (dr)^2 + (r^2 + b^2)( (d\theta)^2 + sin^2 \theta (d\phi)^2 )$$ Where ##b=1## with an orbit only in the equatorial plane. We also know from the question that the orbit must satisfy this relationship: $$\varepsilon = \frac{1}{2} (\frac{dr}{d\tau})^2 + V_{eff}(r)$$ Ultimately, I was tasked to find the initial...
The value of H equals ## 10^{3}## in natural units, According to : https://en.wikipedia.org/wiki/Natural_units, ## t \sim 10^{-21} sec = 10^{21} Hz ##, and since ## \text{GeV} \sim 10^{24} \text{Hz } ##, ## GeV \sim 10^{24} \times 10^{-21} = 10^3 ## in natural units. So is this conversion correct? Also in the above formula, can I convert H to that natural units , since it’s a constant, while keeping k in Hz ?
Back
Top