Recent content by Rib5

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    Calculus What is a good book for learning rigorous calculus?

    Great, thanks a lot for your help! I really appreciate that you tried to understand exactly what it was I needed. I was having a hard time putting into words exactly what my issues were. I will take a look at those two books.
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    Calculus What is a good book for learning rigorous calculus?

    Right now I'm trying to follow some of the proofs for the formula of divergence in Cartesian coordinates. So I'm trying to follow the proof that shows ## \lim_{v\to o} \frac{\oint _S \vec A \cdot d \vec S}{v} = \oint _v \nabla \cdot \vec A dv ## Most of the proofs use a cube, and then find the...
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    Calculus What is a good book for learning rigorous calculus?

    Thanks for the reply! Would you say that these books helped you in not only understanding calculus, but also confidence in using calculus? I guess my end goal is confidence in using calculus for solving difficult EM problems, and possibly understanding some of the proofs for EM theorems.
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    Calculus What is a good book for learning rigorous calculus?

    I'm not sure if the title correctly says what I am looking for. I'm a few years out of college and I'm trying to review some electromagnetics topics. A lot of the "proofs" in my EM book seem to take a lot of shortcuts, or use "intuition" to explain why some calculus operation can be simplified...
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    How many Newtons of force would kill a person?

    Not meaning to ressurect a dead post, but I was hoping someone could help me figure out what to name this type of pysics. I'm going to be working on a safety application as a hobby project, so I was trying to find some concrete material about this type "physics of human safety." I have a...
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    What is the reflection coefficient on a transmission line at a resistor halfway?

    Homework Statement If I have a coaxial transmission line, with a resistor halfway through, and another resistor at the end, how do I calculate the reflection coefficient for the spot where the resistor is halfway? Here is a diagram of what I mean. Dashes and dots are are the lines, and }...
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    Why do some books use dQ/dV for capacitance?

    Thanks for the reply, that explains a lot. It seems like in a lot of books they leave out a lot of the conclusions or assumptions that they make. So basically it can be treated the same as a regular capacitance as long as the change in differential capacitance over the voltage range used...
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    Why do some books use dQ/dV for capacitance?

    Hi guys, Today was the second time in a textbook that they calculated capacitance using C = \frac{dQ}{dV}. In my electromagnetics book and any sources I find online they use C = \frac{Q}{V}. Can anyone help me understand why they can do it like this? This type of calculation was done to...
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    Can autocorrelation be greater than one?

    I have to find the autocorrelation of a random variable. When I compute the theoretical autocorrelation I get the result where it is [1 -2 3 -2 1] centered around zero, and zero everywhere else. I tried estimating the autocorrelation of the random variable using ryy_est = xcorr(Y,20...
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    Why does flux flow through ferromagnetic materials?

    Can anyone help me understand why magnetic flux flows through ferromagnetic materials like an iron ring? Also, say you have a toroid with a wire wrapped around it (in air) how can you say that the flux that goes through one "loop" will go through ALL the others? These are just some things...
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    Need help understanding Fourier transform in Hz vs radians

    So the Fourier Transform is still the Fourier Transform, regardless of what you scale it by? This seems weird because it would mean that if you tell someone, the FT of this is X, it could mean anything unless you give the scaling factor.
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    Need help understanding Fourier transform in Hz vs radians

    Hi guys, I'm having some issues understanding something about the Fourier transform. In my first signals and systems class we used the angular frequency omega. Doing it like that you end up with a weighing factor or 1/(2pi) when you take the transform. Now in the dsp class I am taking now we...
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    What is the pdf of resistor values (tolerances)

    Ah ok, thanks guys. I didn't realize that they actually tested all the components! This makes a lot more sense to me now.
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    What is the pdf of resistor values (tolerances)

    I'm don't care what the tolerance is. My question was about the distribution of values around those tolerances, this way you can predict what values you might get.
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    What is the pdf of resistor values (tolerances)

    I find it hard to believe that no matter how many resistors you bought that you would NEVER get a value outside of the tolerances?
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