Recent content by narfarnst

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    Metric Tensor Questions: Understanding Hartle's "Gravity" Example 7.2

    Hi. This is example 7.2 from Hartle's "Gravity" if you happen to have it lying around. Metric of a sphere at the north pole The line element of a sphere (with radius a) is dS^{2}=a^{2}(d\theta^{2}+sin^{2}\theta d\phi ^{2}) (In (\theta , \phi ) coordinates). At the north pole \theta = 0 and at...
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    Help understanding easy state problem

    Ahhh, well thanks again.
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    Help understanding easy state problem

    Thanks. But why use bra-ket notation? Couldn't you just as easially express them as (a, t). For example, (2, -1) or (1, 1).
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    Help understanding easy state problem

    First off, I don't need a solution, I just need to make sens of the solution I already have. Homework Statement What state of polarization do the following represent (Give your answer in terms of an angle relative to the transmission axis). (a). |t> + |a> (b) |t> + 2|a> (c) 2|t>-|a>...
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    Making a square with point charges (alternative solutions)

    Yes, I get that. That's the method I already know how to do (thanks, by the way. I hadn't actually worked it out yet, but I knew how :) ). I'm asking if there is an easier way to do the problem, namely, one of the two ways I suggested. Thanks.
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    Making a square with point charges (alternative solutions)

    Homework Statement Calculate how much work it takes to make a square of side length A with point charges (all of charge q) at each vertex. Homework Equations The Attempt at a Solution I know one way to do it. (find the difference in potential for each point and then go from there...
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    What is the longest sound wavelength my gym's sound system can support?

    Sorry it's so wordy, my professor's... well he likes wordy problem's I guess. Homework Statement I have very bad acoustics in my gym, where I have a sound system. To model my gym’s sound system, imagine that the gym is a cube 4m in length on each side. It’s empty, and the floor, walls...
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    Very quick triple integral question

    Homework Statement Use the Divergence Theorme to evaluate the flux of v(x,y,z)=x^{2}i+y^{2}j+z^{2}k on the solid T bounded above by a sphere with radius 3 and below by the xy-plane. I've found that div(v) is 2(x+y+z). When I go to set up the integral I get a triple integral over T of...
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    What Are the Tensions and Forces in a Multi-Pulley System?

    Homework Statement http://i829.photobucket.com/albums/zz220/narfarnst/problem.jpg Find T1 through T5 and the force on the right side of the diagram above. (The force balances the weight, so the system is stationary). EDIT: Oh, and the pulleys and ropes are massless and there is no friction...
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