Recent content by silverdiesel

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    Relation between commutator, unitary matrix, and hermitian exponential operator

    Homework Statement Show that one can write U=exp(iC), where U is a unitary matrix, and C is a hermitian operator. If U=A+iB, show that A and B commute. Express these matrices in terms of C. Assum exp(M) = 1+M+M^2/2!...Homework Equations U=exp(iC) C=C* U*U=I U=A+iB exp(M) = sum over n...
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    Ultraviolet catastrophe and quantization

    Plancks hypothesis was simply that E=hv. This is so common now its hard to think otherwise. In fact, in your question, you stated the answer. What you claim is classical, is actually quantum. Higher energy = higher frequency. Classically, higher energy = higher amplitude. So...
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    Jumping perpendicular out of a fast spaceship will retain your speed right?

    Yes, that is exactly correct. Thinking about space dynamics is the best way to understand F=ma. You will continue to have the same velocity until acted on by some outside force (jetpack, tethered line). Its a bit hard to fully grasp here on earth, because we are constantly acted upon by...
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    What is the Science Behind Electric Shock and Grounding?

    Sounds like you understand it pretty well. The analogy between pressure and voltage (potential), is a good one. In fact, they are almost the same thing because pressure is the product of the electrical repulsion between electrons bound within atoms, and potential is the product of electrical...
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    How do I integrate inverse root functions in calc 2?

    wow. 3 years later, and yes, I think I've finally figured it out. So, I am sitting at my desk trying to wrap my mind around the Kroneker Delta and the Levi-Civita Symbol. I do a google search for info, and a thread on my old friend, the Physics Forums pops up. I click the link, read...
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    Is Taking 12 Credits Enough for a Freshman Math and Physics Double Major?

    hmmm, I know you don't have to say, but what school is this? I am only asking because it seems like such a strange schedule for a freshman. I am guessing you took the calc and gen phys in high school? What about core classes? Does you school require you to take English or Geography or...
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    Confused by my modern physics class

    Interesting Thread. I am taking Modern right now as well. I think there are two students (out of ~30) that seem to be understanding the material. The average on the last test was in the forties. We are using the Bernstein, Fishbane, and Gasiorowicz book, which I dislike very much. I have...
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    What is the magnitude of the Electric field inside a light wave?

    Nevermind, I finally found it in my gen phys 2 book derived from the Intensity. 1300 W/m^2 ~ 1000 N/C
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    What is the magnitude of the Electric field inside a light wave?

    I know the magnitude varys a lot, but I am just looking for some basic intuitive idea of light. Is the magnitude of light from my computer screen on the order of 10^6 N/C or more like 10^-6 N/C?
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    Convert linear density to area and volumetric density?

    It is a square (not a cube, a flat square surface)
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    Calculating Acoustic Pressure for 10 W/m^2 of Intensity

    The velocity of sound in air of density rho=1.29 kg/m^3 may be taken to be 330m/s. Show that the acoustic pressure for the painfull sound of 10 W/m^2 ~ 6.5x10^-4 of an atm. (atm~10^5 N/m^2) What is acoustic pressure. This question is easy I am sure, but I don't really know what it is...
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    Convert linear density to area and volumetric density?

    if I am given a area density of 10^-4, I can get linear and volumetric density from that right? I just can't seem to figure it out.
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    Choosing Between CU Boulder vs CU Denver: My Experience as a Physics Major

    I am currently attending the University of Colorado at Denver pursuing a second undergraduate degree in physics. My original plan was to take the basic classes at CU Denver and then transfer up to Boulder for the remainder of the degree. (I live in Denver, and Boulder is a 45 minute commute)...
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    I know the material inside and out, but then make dumb mistakes on tests

    excellent topic. I am 27 and in the middle of a second bachelors on physics. I flunked out of the physics program the first time, and had to choose a different major. The reason I flunked out was due to test anxiety, so I am very familiar with making stupid mistakes. However, the second time...
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    Mathematica Should I invest in mathematica?

    I went ahead and purchased mathematica yesterday. Good stuff. It was able to confirm the solutions to a couple 3x3 determinants I have been working on (all symbolic, no numbers).
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