Recent content by dominicfhk

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    Orbital elements - what's wrong with my calculation?

    Homework Statement Ok so this satellite is orbiting the earth. The position vector is r = -0.707i + 0.707j + 0k and velocity vector is v = 0i + 0.5j + 0k. To find Vo (the angle between vector n and e), my book said the formula to use is arccos{(e dot r)/(|e||r|)}. However, I got 98 degree by...
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    Resonant Frequency & Natural Frequency?

    Hello guys! Is it possible to convert a natural frequency to resonant frequency with maybe some kind of formula? I was given a transfer function and I was asked to draw a root locus plot and determine the resonant frequency. I know how to get the damping ratio and natural frequency and the value...
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    Gain & Transfer Function - Difference?

    I know the transfer function = Laplace{output}/Laplace{input}, while gain = output/input, but why is that matter? The ratio will still be the same (or is it?). And if there is a distinct different, is the result of the mason's formula using signal-flow graph a gain or a transfer function...
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    How to find cutoff frequencies from Bode plot?

    Homework Statement http://img832.imageshack.us/img832/7517/captureax.jpg According to the solution, the cutoff frequencies are 1, 20, 80, 500 and 8000. I don't understand how to get those answers by inspecting the plot. Homework Equations None The Attempt at a Solution I think the...
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    Get transfer function from bode plot

    Nevermind, I think I got it. Thanks.
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    Get transfer function from bode plot

    Homework Statement What is the transfer function described by this bode plot: http://img96.imageshack.us/img96/4775/capturegib.jpg *The answer is 3s, but I don't know where it comes from. Homework Equations None The Attempt at a Solution Correct me if I am wrong. A bode plot is a...
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    What is the Transfer Function of an Open-Loop System?

    Homework Statement Hi, guys. I am watching this guy on youtube explaining block diagram of close and open loop system. While I understand how a close-loop transfer function is equals to C(s)/R(s) = G(s)/{1+G(s)H(s)}, I don't quite understand how the transfer function of an open-loop system...
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    Why is Y=mx+b considered a linear function despite failing linearity tests?

    I understand that a linear relation needs to satisfy both the property of superposition and homogeneity. Y(x)=mx+b does not satisfy both property at the same time yet any equations in this form are called a "linear function" and it is used in linear approximation. For example, sin(x), which is...
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    3rd order differential equation

    Homework Statement I took differential eq-n class more than a year ago and I am having problem solving this problem. 5(d^3y/dt^3)+3(d^2y/dt^2)+7(dy/dt)+y = 4(d^2f/dt^2), where f(t)=cos(t)-2sin(t) Homework Equations none The Attempt at a Solution First thing I did was to take the...
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    How to know if a system is dissipative?

    Hi guys. I got stuck in this problem and I am wondering anyone can help. Homework Statement For the the linear system describe by d^2/dt^2 y(t) + (5)d/dt y(t) + (6)y(t) = f(t), where f(t) is the input to the linear system, and the solution to the differential equation is the response of...
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    Engineering Signal flow graph, describing a RC circuit?

    Signal flow graph, describing a RC circuit? Hi, guys. This is my first post on this forum! I'm trying to understand this example in my textbook. The current and voltage equations are: where G=1/R, Z(s)=1/Cs, and I1(s)=I1 Then the text says the following signal flow graph can be obtained: And...
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