Recent content by badphysicist

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    Calculating the max distance of compression of the spring HELP

    There is extra gravitational potential energy from the distance through which the spring drops through while touching the spring. In other words, the total distance that the object drops is 40 cm plus however far the spring compresses.
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    How to show the ground state is orthagnol with the first in a quantum harmonic os

    You have the wrong equation for \psi^1. See http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/hosc5.html#c1" for the correct wave functions. You should be integrating from -infinity to infinity though because the standard quantum harmonic oscillator doesn't have finite bounds on it. And yes...
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    What is the Harmonic Vibrational Frequency of a 39^K 35^Cl Molecule?

    There is one positive charge on the potassium and one negative charge on the chlorine. The attractive force is from these two opposite charges. It sounds to me like you are supposed to treat the repulsive force as being spring-like. You also know the distance between the atoms when the forces...
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    Why is the ground state always symmetric?

    I think that second way that jasony phrased his question is really more of what he is aiming for: why does the ground state have no nodes? Correct me if I'm wrong jasony.
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    Why is the ground state always symmetric?

    The greater the curvature of a wave function, the more kinetic energy that it has. Wave functions with nodes have more curvature than nodeless wave functions. Since we are trying to minimize the energy, it makes sense to me that wave functions with no nodes would be good candidates to be the...
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    What Capacitance is Needed to Tune an LC Circuit to 100 MHz?

    My advice is to figure out what quantity microH goes with and which quantity MHz goes with. They can't both be f unless microH and MHz are the same unit, which they aren't.
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    Deriving the effective potential due to screening

    The logarithm diverges, but it is multiplied by 0 (for the first term in the Taylor expansion).
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    Physics graduate can't get job with defense contractor

    Having been a summer intern at Sandia, I know that there is the possibility of them paying for your MS if they want to keep you on. I kind of wish that I had taken them up on that sort of an offer but with a PhD. They pay pretty well and treated me well. I just wasn't interesting in staying in...
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    Use of Monte Carlo Method to Solve Geometrical Problems in Radiation Transfer

    This can definitely be solved using Monte Carlo simulations. However, there are already packages to do this. http://view3d.sourceforge.net/" can calculate the view factor for both 2D and 3D configurations. I haven't looked closely at this program so I don't know how it does its integrations...
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    MATLAB Trying to speed up some MATLAB code

    Is T completely allocated before you run the loop? If you have only assigned the first matrix in T, meaning T(:,:,1), then every time through the loop it is allocating memory for the next matrix. This can add very significantly to the matrix. It is better to do something like T =...
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    Is the Radial Wave Function R_{31} Normalized Correctly?

    Well, it looks like you didn't in your equation with the u's.
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    Interpolation Formula in MATLAB | Solving for y(ti) with Code Example

    Before the first loop, I would set up the y's(actually, it would be faster for your code to init the t's to zeros to, but unless n is very large it shouldn't matter): y = zeros(n+1,1) Then in the loop it would be something like y(j) = 3 + sum( y(1:j-1).*(1:j-1) ) the .* does an element-wise...
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    How Fast Does a Stapling Gun's Ram Move at Impact?

    Conservation of energy. U_0 + KE_0 = U_f + KE_f. Think about each of these terms and what their values are initially and finally for this situation.
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    Computational Phy. Methods and Sim. (question)

    I'm a graduate student in physics doing computational physics. The codes I work with have all been in C++, but I also use a lot of Matlab and I feel that Python will be used increasingly in the future. I don't know Fortran, but I have had to read Fortran a few times and had no problem from my...
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    Is the Radial Wave Function R_{31} Normalized Correctly?

    Remember what coordinate system you are working in.
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