Recent content by dydxforsn

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    News Be optimistic about America

    Here's an interesting quote I read recently that has to do with this: “Those who fail to exhibit positive attitudes, no matter the external reality, are seen as maladjusted and in need of assistance. Their attitudes need correction. Once we adopt an upbeat vision of reality, positive things...
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    The Secret on how men can attract women

    I've heard it being included in girls' top 3 things a couple of times. One girl in particular that I thought I liked in college was very fervent about it.
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    Chemistry How many moles.

    If you have one mole of the compound, and if there is one atom of magnesium per compound, then how could you have anything other than one mole of magnesium?
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    First year undergrad - will chemistry be useful?

    I would just take some kind of a basic, chemistry isn't really a course that provides the foundation for anything in physics so there's not really a reason to get to it early. It's not getting you into some sequence early so that you can then take a multitude of advanced courses as a result...
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    Career prospects with either EE or CompSci

    heheh, your priorities are correct. It was once that people were debating which majors were better for the pay, now people are simply debating which major actually provides a real job! Heh, both computer science and electrical engineering are great, and from my experiences in life, they're...
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    First year undergrad - will chemistry be useful?

    I would take basic chemistry later in your degree, as it will be a nice simple break from your more difficult physics courses, though you need to budget the time for the busy work that is 90% of your time dealing with chemistry labs. Further, after you have a foundation in basic physics and...
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    Programs Electromagnetism for an Electrical Engineer Major?

    I used the Griffith's book for electrodynamics for my physics undergrad. After finishing the course a year later I ended up tutoring a good friend who was doing the equivalent electrical engineering course. I went over antennas, transmission lines, waveguides, and plane waves at dielectric...
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    Meteorite crash in Russia

    heh, the quote in that asteroid picture reminds me to check Neil Tyson's twitter..
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    Electromagnetic Induction

    According to the beginning of this episode of the Mechanical Universe, this situation was a starting point for Einstein's special theory of relativity (fast forward to 1 minute 22 seconds):
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    Mole, Molar mass and Avogadro's number

    Well, grams are what's important in the macroscopic world of the humans, so we want to discuss masses of things in grams. However, if one were to label the masses of the various elements of the periodic table in terms of their weight in grams, there would be a nasty 10^{-23} factor on all of...
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    Capacitor help needed (voltage needed and time constant question)

    For part one you're simply using Q = CV where 'Q' is the charge of the capacitor, 'C' is the capacitance, and 'V' is the voltage required to do so. To get the electric field from the spacing and the voltage you just need to use the equation E = V/d (E is the rate at which V changes with...
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    Favourite Quotes

    Thanks, heh, it was a good one. Also, everyone should check out or remind themselves of the great Howard Zinn today:
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    Favourite Quotes

    "Freedom isn't free. It shouldn't be a bragging point that 'Oh, I don't get involved in politics,' as if that makes someone cleaner. No, that makes you derelict of duty in a republic. Liars and panderers in government would have a much harder time of it if so many people didn't insist on their...
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    Simple time-independent non-degenerate quantum perturbation

    Ok, that definitely cleared everything up. Thank you for everything, I especially wouldn't have guessed that they were expanding corrections to the eigenstates in terms of unperturbed eigenstates. Wow, you'd think that would have been a part of the derivations they would have spent more than...
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    Simple time-independent non-degenerate quantum perturbation

    I'm reading through this pdf ( on simple quantum perturbation theory and I'm quite confused with equations 32 through 34. They have E_{n}^{(2)} = <n^{(0)}|V|n^{(1)}> = - \sum_{m \neq 0}{\frac{|V_{mn}|^{2}}{E_{mn}}} but I would have done E_{n}^{(2)} =...