Recent content by Feldoh

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    The design of a low pass filter

    It's actually kind of hard to go from square wave -> sine wave. What you really want isn't a low pass filter but a band pass filter about 50Hz. This is basically what you're building with the inductor, resistor in parallel with a cap. You're impedance is going to go down just because it's...
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    Astronaut in space, calculating velocity etc

    The final velocity is in an opposite direction (towards the spaceship) compared to the initial velocity (away from the spaceship). If you take the difference of the two you need to consider the signs (direction) of the velocities. The way you're currently taking the difference you are assuming...
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    Astronaut in space, calculating velocity etc

    \Delta v = v_f - v_i right? You should recalculate that again. Also, I don't think that 1,225 m/s is the correct answer.
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    Solving the Shroedinger equation for a harmonic oscillator potential

    Because he wanted to motivate the decision to use a power series. In my copy Griffith's even makes a footnote stating that this is, as you reasoned, the idea behind solving diff. eq's using power series.
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    Astronaut in space, calculating velocity etc

    So to solve this problem you'll need to think about the directions of the astronaut and the tool both before and afterwards. In your answer you assume that the astronaut is traveling in the same direction both before and afterward he throws the tool. How would you correct this?
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    Measuring Voltage Across Two Points In A Series Circuit

    I'm not entirely sure about the polarity on the batteries (I just guessed in my schematic). If my schematic is correct then you have the correct current for your circuit given my Ohm's law as you calculated: 19V / 12Ohm = 1.6A -- So what can we say about the current through each resistor? Also...
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    Net Resistance of Parallel Circuits: Solve It Now!

    Your answer and the books answer are the same. They just multiply the fractions so there is a common denominator (However odd that denominator is)
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    Net Resistance of Parallel Circuits: Solve It Now!

    Well what have you tried so far?
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    Laplace transform in electrical engineering

    I don't know what system you're trying to solve but if you just look at the Laplace transform for a single capacitor You have i(t) = C \frac{dv}{dt} <==> i(s) = C(s*V(s) - V(0)) ==> V(s) = \frac{i(s)}{sC} + \frac{V(0)}{s} Notice that i(s) and V(s) both have an s dependence. s is defined as...
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    Complex: Defining Sqr(-1) in Main Branch of logz

    Are you having trouble because you think Log(z) is undefined along the negative real axis? We can extend logarithms into the complex plane quite easily actually: http://en.wikipedia.org/wiki/Complex_logarithm
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    Is it true that fluid and thermo dynamic are difficult?

    Two reasons: 1.) Anything useful is numerical simulations (most of which have been written for you) 2.) Non math majors are not in the best position to learn a lot of the mathematics involved.
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    Minimum velocity for a sonic boom?

    You're just arguing semantics at that point. Technically you are correct assuming you think space is a continuum but based on how the question is phrased I believe you knew what your teacher really wanted and it would have been very easy to write it down.
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    EE related Math topics/courses

    From my experience taking graduate level EE courses I've needed to know some abstract algebra (probably the most useful thing to know), and secondly PDE's and probability. However my class experience is limited to random signals course and an advanced fields course.
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    Physics majors Elec & Mag vs. EE majors

    I'm just speaking of my experience as a physics/EE double major and so I can't comment for everyone. Physics advantages: Mathematically more rigorous which lends itself to quite a lot of areas of electrical engineering. Communications, nano/micro fabrication, fields, just to name a few. In...
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    Shift left and right registers

    What do you mean binary weighting?
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