Recent content by Yitzach

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    Relativistic Momentum Operator

    I think that analytically will be easier on the processor(s) and so I would like as many analytical solutions as possible. But I suspect that eventually, there will be a need for numerical solutions. Numerical is just a little hard on CPU's if you are lacking with that in your computer.
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    Relativistic Momentum Operator

    Let's (mostly me) try this again. I have the following: \Psi_n(x)=\sqrt2\sin(n\pi x)\ x\in[0,1] |\Psi_n(x)|^2=2\sin^2(n\pi x)\ x\in[0,1] \Phi_n(p)=\frac{1}{\sqrt{2\pi\hbar}}\int^\infty_{-\infty}e^{-ipx/\hbar}\Psi(x)dx\ x\in[0,1],p\in\Re3.54 \Phi_n(p)=\frac{\pi...
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    Relativistic Momentum Operator

    Perhaps I wasn't quite clear. I have the wavefunction in "configuration" space for the infinite square well which does a very nice job of giving a probability distribution for where the particle should be. I want the probability distribution for the momentum of the particle. Getting the...
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    Relativistic Momentum Operator

    I have in mind to build a game to help teach or demonstrate some concepts in QM and I thought it would be nice to be able to measure momentum. So as a proof of concept before I get too many man hours burned on the project I thought it would be good to do the infinite square well. I managed to...
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    Ohm's Law in a sphere with current density

    There is nothing I can do to remove the electric permittivity of the "weak conductor." http://en.wikipedia.org/wiki/Permittivity#Classification_of_materials" says that a material is considered a poor conductor when "\frac{\sigma}{\omega\epsilon}<<1" meaning the electric permittivity could be...
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    Ohm's Law in a sphere with current density

    I am familiar with it in the form of \vec{J}=\sigma\vec{E} where sigma is the conductivity which is equal to the multiplicative inverse of rho, which was used. I'm not sure what you are purposing as I don't have the current density to find the current with. The current density was found from the...
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    Ohm's Law in a sphere with current density

    As noted in the attachment: \vec{J}=\frac{Q\sigma}{4r^2\pi\epsilon} But the current is constant through any sphere between a and b, inclusive. Failure to do so suggests that the current curls. But because the current follows the E-field, which doesn't curl in this case, and there is no...
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    Ohm's Law in a sphere with current density

    That works much better. The two currents and resistance are not dependant on position and they are not negative. I decided to assume a charge Q instead of a potential V and found the E-field using Gauss's Law in integral form. 1a) \vec{I}=\frac{\sigma Q}{\epsilon}\hat{r} 1b)...
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    Ohm's Law in a sphere with current density

    Homework Statement Two concentric metal spherical shells of radius a and b, respectively, are separated by a weakly conducting material of conductivity sigma. (a) If they are maintained at a potential difference V, what current flows from one to the other? (b) What is the resistance between...
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    Frobenius method aplied to simple harmonic oscillator problem

    You want to derive the MacLaurin series, not use them to reach the answer. a_(2n) will be a_n of the cosine MacLaurin series. a_(2n+1) will be a_n of the sine Maclarin series. By working it backward you would end up proving that the results of the method work...
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    Frobenius method aplied to simple harmonic oscillator problem

    You are working the problem backwards. You want to assume a power series expansion is a solution to the problem. y=\Sigma_{i=0}^\infty a_nx^n You can then take the derivative of that twice so you can find y". You can then plug the series into the equation and solve for a_n and you will end up...
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    Permissibility of Limit Technique

    Fair enough. So is there a reason for real numbers? Yes I was aware of other methods. I was wondering about the permissibility of what I did for if I wanted to do it again later. Notice that I mentioned four other methods in the initial post.
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    Permissibility of Limit Technique

    By what you said here, I take it to mean that once an answer has been arrived at by this method, it would be advisable/required to check 0 and infinity to make sure that they are not the answer. In this case I knew that neither of those could be the answer based on the nature of the question and...
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    Permissibility of Limit Technique

    The following came from a step in my EM homework. I came up with the answer that all of my resources (calculator, WolframAlpha, and a friend) were indicating as the correct answer, so it is not about the homework. This is about the permissibility of what was done. 1...
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    Probability of randomly bouncing speedometer (stubborn calculus)

    I did drop the pi^-1. GIGO. TI-89 Titanium only knows what I tell it. Nicely caught. And that sigma makes complete sense now that it is less than one whole r.
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