Recent content by Lunar_Lander
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Optimizing Hydrogen Atom Wave Function Expectation Values
I think I got <V>, the first solution I posted was from the indefinite integral. A^2\frac{e_0^2}{\epsilon_0}\int_0^{\infty}\exp(-2\alpha~r)r~dr A^2\frac{e_0^2}{\epsilon_0}\cdot\frac{1}{4\alpha^2}=\frac{e_0^2\alpha}{4\pi\epsilon_0}. Also, A can be found by normalizing the original wave...- Lunar_Lander
- Post #9
- Forum: Advanced Physics Homework Help
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Expectation Values of Radii in the Hydrogen Atom
I think I got it now. First of all I learned that the 2p energy level is degenerate, thus m should have no influence on it and there is only one calculation to do for 2p. Then I tried to calculate 1s: \psi_{1s}=\frac{1}{\sqrt{\pi}}(\frac{Z}{a_0})^{3/2}\exp(-\frac{Zr}{a_0}) As we are...- Lunar_Lander
- Post #3
- Forum: Advanced Physics Homework Help
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Expectation Values of Radii in the Hydrogen Atom
I also attempted a run at the 2p (for m=0) and it looks like this: \psi_{2p_0}^2=\frac{1}{32\pi\cdot a_0^5}\cdot r^2Z^5\exp(-\frac{2Z\cdot r}{a_0})\cdot\cos^2(\theta) <r>=\frac{1}{32\pi\cdot a_0^5}\int_0^r \int_0^{\pi} \int_0^{2\pi} r^2Z^5\exp(-\frac{2Z\cdot...- Lunar_Lander
- Post #2
- Forum: Advanced Physics Homework Help
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Expectation Values of Radii in the Hydrogen Atom
Homework Statement Determine for the hydrogen atom states 1s and 2p the expectation value of the radius r and the associated mean square error Δr. Homework Equations Wave Functions for 1s and 2p from Demtroeder's Experimental Physics Volume 3 (it says "The normalized complete...- Lunar_Lander
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- Atom Expectation Expectation values Hydrogen Hydrogen atom
- Replies: 2
- Forum: Advanced Physics Homework Help
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Optimizing Hydrogen Atom Wave Function Expectation Values
Sorry, I had once seen this notation (T=\frac{\hbar}{2m}\Delta) somewhere. Would it rather be: <T>=-\int\int\int r^2\cdot\sin(\theta)\cdot\psi^2\cdot\frac{\hbar}{2m}\Delta\psi~dr~d\theta~d\phi ? I'll try the limits later on, but thanks for the help already :)!- Lunar_Lander
- Post #7
- Forum: Advanced Physics Homework Help
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Optimizing Hydrogen Atom Wave Function Expectation Values
So, I am getting this: -4\pi\cdot A^2\frac{e_0^2}{4\pi\epsilon_0}\int \exp(-\alpha\cdot r)\cdot r~dr -A^2\frac{e_0^2}{\epsilon_0}\int \exp(-\alpha\cdot r)\cdot r~dr and A^2\frac{e_0^2}{\epsilon_0}\cdot \frac{1-\exp(-\alpha\cdot r)\cdot (\alpha\cdot r+1)}{\alpha^2} Is this correct? If...- Lunar_Lander
- Post #5
- Forum: Advanced Physics Homework Help
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Optimizing Hydrogen Atom Wave Function Expectation Values
Thank you Vela! Would it maybe be possible for one of you to show me just how to correctly do this calculation, because my problem is that I usually need a good example and explanation on how to calculate complex things. When I look at calculations in books, those are usually good, but when I...- Lunar_Lander
- Post #3
- Forum: Advanced Physics Homework Help
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Optimizing Hydrogen Atom Wave Function Expectation Values
"Optimizing" a Wave Function Homework Statement Consider a Hydrogen Atom, an electron in an attractive Coulomb potential of the form V(r)=-\frac{e_0^2}{4\pi\epsilon_0r}, where e0 is the elementary charge. Assume the following wave function for the electron (with α>0): \psi(r)=Ae^{-\alpha...- Lunar_Lander
- Thread
- Function Wave Wave function
- Replies: 9
- Forum: Advanced Physics Homework Help
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Wave Functions in a Potential Well with infinite high walls
Homework Statement Consider a potential well with infinite high walls, i.e. V(x)=0 for -L/2\leq x \leq +L/2 and V(x)=\infty at any other x. Consider this problem (the first task was to solve the stationary Schroedinger equation, to get the Energies and Wave Functions, especially for n=1 and...- Lunar_Lander
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- Functions Infinite Potential Potential well Wave Wave functions
- Replies: 1
- Forum: Advanced Physics Homework Help
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Free Particle and the Schroedinger Equation
Ah, thank you! When I take the complex conjugate of ψ for taking the square, then I get \rho(x,t=0)=\frac{1}{\sqrt{2\pi}d}\exp[-\frac{(x-x_0)^2}{2d^2}]. Looks like a gaussian bell curve to me from the form of the equation. Could that be it?- Lunar_Lander
- Post #4
- Forum: Advanced Physics Homework Help
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Free Particle and the Schroedinger Equation
An addendum, just received an E-Mail from the professor, who said that due to many people having difficulties, he would give the solution for ψ, and he said it looks like this: \psi(x,0)=\frac{1}{\pi^{1/4}\cdot 2^{1/4}\cdot d_0^{1/2}}\exp[i\cdot k_0(x-x_0)]\exp[-\frac{(x-x_0)^2}{4d_0^2}]...- Lunar_Lander
- Post #2
- Forum: Advanced Physics Homework Help
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Free Particle and the Schroedinger Equation
Homework Statement Consider the time-dependent one-dimensional Schroedinger Equation for the free particle, i.e. let the Potential be V(x)=0. Consider a wave packet, i.e. \psi(x,t)=\int_{-\infty}^{\infty}=A(k)\exp[i(kx-\omega(k)t]dk. Consider especially the Amplitude distribution...- Lunar_Lander
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- Free particle Particle
- Replies: 3
- Forum: Advanced Physics Homework Help
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What is the focal length of the second lens in an afocal system?
For clarification, here is a picture of the system I am asking about.- Lunar_Lander
- Post #2
- Forum: Introductory Physics Homework Help
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What is the focal length of the second lens in an afocal system?
Homework Statement An object at a distance a1 in front of a convex lens with the focal length f1 is imaged at a distance b1. A second lens at the distance d from the first lens with the focal length f2 is then imaging this Image with the image distance b2. a) Give the image distance b1 as...- Lunar_Lander
- Thread
- Lenses System two lenses
- Replies: 2
- Forum: Introductory Physics Homework Help
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What Is the Electric Field Strength in a Glass Sphere with a Point Charge?
OK, thanks :)! In the metal, there should be a shift of charges due to the field from the inside, so that the inside of the metal layer is free of the electric field, i.e. |E(r)|=0? One last pointer on the fields inside though, please. Do I need to incoporate the radius of the glass sphere...- Lunar_Lander
- Post #3
- Forum: Introductory Physics Homework Help