Recent content by BAnders1

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    Calculate Resonance Frequency of a Molecule

    I remember calculating the resonance frequencies of a water molecule using classical mechanics. We use Lagrangian mechanics and modeled each atom in the molecule as a point mass, and we assumed the force between each atom was proportional to their separation (like Hooke's law). I imagine...
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    How to measure berry phase?

    I'm looking at D. J. Griffiths' intro to QM. I regards to Berry's phase he says one could split a particle beam into two, have one part go through an adiabatically changing potential, and recombine the beams and measure the new wave function (definitely open-ended). According to the Feynman...
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    Help for quickest and clearest route for differentiation question

    Try substituting z = x^(1/2), then cast the result into the form az^2 + bz + c = 0.
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    US running out of places to store money

    Last time I paid in coins it was $2.75 in quarters, hardly a burden to count, but the cashier paused and gave me an extended dirty look. I don't use coins anymore because I don't want to leave the store as angry as I did that day.
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    Confusion with understanding derivatives in respect to

    A derivative can be thought of as a rate of change of a variable. The expression dx/dy in English is "the derivative of x with respect to y." What this means is that we are looking at the rate at which x changes when y changes. In physics you might be interested in an object's speed. If the...
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    Einstein Velocity addition

    What is X exactly? By the way, common sense will lead you to dark alleys and beat you to death in physics.
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    Pondering an old quote from Maxwell

    During Maxwell's time, the theory of vector calculus was not well-established. Also, much of the vocabulary of his day is obsolete. I tried reading Maxwell's "Treatise on Electricity and Magnetism" and I found that it took way too much concentration to follow his ideas (but it made me...
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    Normal force: Why not conservative?

    In my head I'm imagining a block glued to a surface that is free to rotate from an axis some distance away from the block. If the surface rotates 360 degree, it is back where it started, but not before doing some work on the block. I'm used to thinking of conservative forces in terms of the...
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    Maxwell's A Treatise on Electricity and Magnetism

    Out of date indeed. Charges in the book are called resinous or vitreous instead ofnegative and positive, and several of the concepts we have today are nowhere apparent (or at least not directly mentioned). The concept of the electric field is not directly mentioned in the book. As a matter of...
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    Wave Collapse and Degenerate States - A Quick Question

    Let's say you have some quantum particle whose eigenvalues for some observable Q are either degenerate or non-degenerate. If you measure the observable and find it to be in a non-degenerate state, then you know that the wave function has collapsed onto this state. Now if you measure the...
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    MIT series on Electromagnetism

    I was just about to post this haha. There are also introductory mechanics lectures 8.01 at: http://www.youtube.com/view_play_list?p=F688ECB2FF119649&search_query=MIT+8.01" and vibrations and waves 8.03: http://www.youtube.com/view_play_list?p=854AA255B15C574C&search_query=MIT+8.03"
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    Maxwell's A Treatise on Electricity and Magnetism

    Maxwell's "A Treatise on Electricity and Magnetism" I bought this book as a supplement to my electromagnetism I class, but the moment Maxwell goes into anything mathematical, I'm lost. The lack of illustrations and reference to many out-dated terms makes the book hard to follow. The book is a...
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    My Dilemma With Physics (Engineers please read too!)

    My university offers a "physics engineering" degree which acts as a kind of hybrid between science and engineering. Perhaps your college offers something like this. The best bet is to talk to an academic adviser. I hope everything works out for you.
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    Does anyone have any recommendations as to how to assign error to this?

    I once had a lab assignment in which we used FFT's to measure the speed of sound. We took the full width at half maximum (in frequency space) as the error estimate in our measurement for the frequency.
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    Drawing the short straw

    1 In theory, the only condition required for the water in the straw to hover is that the force pushing the water down (mg) is equal to the force pushing the water up (PA) where P is the pressure difference between the top of the water and the bottom. Now for a circular lake of diameter...
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