Recent content by widderjoos

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    Orbital Angular Momentum Origin

    Yeah, that's what I was thinking, but just wanted to make sure since I couldn't find it explicitly stated anywhere. Thanks!
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    Orbital Angular Momentum Origin

    We know from classical mechanics that angular momentum L = r \times p depends on your choice of origin. My question is: How does this work quantum mechanically? We know we get certain eigenvalues, but does this apply only in a certain choice of origin? How do we calculate angular momentum at...
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    How are ultra cold temperatures measured?

    Thanks, this helped a lot
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    How are ultra cold temperatures measured?

    Thanks, but how do they measure the velocity distribution without significantly heating the system up?
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    How are ultra cold temperatures measured?

    How are ultra cold temperatures measured? For example, sometimes I see things measured in nanoKelvins. I'm thinking there has to be direct contact since the vacuum is already hotter than this, but how is it actually done?
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    Mathematics of Classical and Quantum Physics

    I'm currently about halfway through the book by Byron and Fuller and it's one of the best books I've seen. He offers physical intuition and insights to otherwise very technical mathematics. There were some points I couldn't follow due to lack of experience, but if I spent enough time, I usually...
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    Does air behave like an ideal gas

    I think you can get away with assuming air is an ideal gas most of the time, as long as temperatures, pressures, and volumes are normal (like room temperature, etc.), but my answer might be kind of vague.
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    Commute an operator with a constant

    oh you're right, but it still doesn't equal 0 though unless I'm missing something again
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    Commute an operator with a constant

    Homework Statement Suppose we had an operator A that multiplied a vector by it's norm: A \mid \psi \rangle = \langle \psi \mid \psi \rangle \mid \psi \rangle I wanted to know what it's commutator with a constant would be. Homework Equations \left[A,B\right] = AB - BA The Attempt at...
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    Quadrupling radius of satellite in orbit

    Yay, I understand it, thanks!
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    Quadrupling radius of satellite in orbit

    Thanks for the helpful reply. There's one thing still bothering me though. Suppose we had circular motion of some satellite and for some reason, it wanted to adjust it's radius using it's with 2 well placed thrusts: one radially outward to get it to a larger orbit, and a second to keep it...
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    Quadrupling radius of satellite in orbit

    It was a problem on a practice MCAT thing and the answer used Newton's gravity equation. (I guess they were assuming uniform circular motion as well)
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    Quadrupling radius of satellite in orbit

    Homework Statement If a satellite in orbit changes it's orbiting radius to 4 times its initial one, how does it's velocity change? I get different answers by using Newton's Law of gravitation and conservation of angular momentum. Homework Equations F = \frac{G M m}{R^2} a_c =...
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    Preperation reading for a physics summer course

    I think Giancoli's Physics Principles book is more algebra based (rather than calculus based), so if you're going into physics, a book that would be more useful in the long run would be Giancoli's Physics for Scientists and Engineers (or something similar). The latter worked well for me.
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    Best all time mathematicians/physicists.

    I think the people who had the greatest impact on physics are: Galileo Maxwell Weyl Einstein For math: Gauss Hamilton Riemann (Emmy) Noether for having important contributions (imo). Personally, I admire Kitchen and Feynman who got me into math and physics through their...
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