Recent content by spaderdabomb

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    Physicality of a force from Taylors CM

    Well I was mostly referring to the exact equation when I said I couldn't think of anything in nature that models it. But...depends what you call nature. The discharge time of a capacitor? Well...that follow this equation multiplied by a few constants almost exactly. But does that count as...
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    Physicality of a force from Taylors CM

    I don't think it is necessarily a better approximation for drag. I mean I guess it depends what you are comparing it too? Certainly there are better models of drag (although, have you know it, the Navi-Stokes Millenium problem deals with this exact problem, and it hasn't been solved!). But on...
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    Euler Angle transformation, help

    Think I figured it out. All I had to do was write a program that constantly gave the difference in the euler angles of the two coordinate systems. Then I took the original vector (pointing in the -z direction of my probe's coordinate system) and did the inverse transformation using the inverse...
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    Euler Angle transformation, help

    I'm doing a research project currently and basically what I have is a camera measuring a probe. I have designed the camera to give the orientation of the probe using euler angles in the camera's frame of reference. This was working for most of my data, but now I need a 3-D visualization of what...
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    System of three, 2nd order diff. equations

    I would form a matrix. You should get a 3x1 on the left side equaled to a 3x3 times some constants that you need to solve for. Solve for the eigenvalues and eigenvectors.
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    Method of Undertermined Coefficients

    Well I think it does have to do with the number of times you differentiate in a way, but in other cases it could depend on your coefficients (sorry I know I previously told you to forget about coefficients, but in some rarer cases such as this one it can come up). Think about the top equation...
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    Method of Undertermined Coefficients

    Also from your previous post I just wanted to make sure that you knew that you don't just "discard" a solution. That imaginary solution you obtained was no solution at all...I checked and it did not satisfy the initial equation. It is simply not a solution, rather than a solution you just discard.
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    Method of Undertermined Coefficients

    You are supposed to guess to some extent, but it should be a VERY good guess (or in other words...there is a method to this madness that should get you the right guess almost every time). to keep it simple, your Y(t) should take on a similar form in terms of its functions. So what I mean is...
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    Diff EQ - Imaginary identities

    Well look at it this way. If you cube your solutions of r, you should get -1. What is (-1)^3? Well, (-1). That tells me that (-1) MUST be a solution
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    Diff EQ - Imaginary identities

    Are you sure your r values are correct? Now that I am looking back over it I would think that r = (-1) should be one of your values since in your characteristic equation you get r^3 = -1 If r = -1 then were in business!
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    Diff EQ - Imaginary identities

    So your last value should fit the form Ce^{rt} for this particular problem. Since your value is r = -1/2 + 3i/√2, we get e^{(-1/2 + 3i/√2)t}. This still presents a problem though hmmm
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    Diff EQ - Imaginary identities

    Well you have your values for the homogeneous solution, so now you need to find the values for your particular solution. There are a number of methods that apply to higher order differential equations that are the same for second order differential equations. Try using one of those methods. Then...
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    Manipulating a formula for a relativistic Doppeler shift

    Im not sure which images you are talking about...you sure they were uploaded correctly?
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    How long for 2 particles to collide due to gravity?

    Using energy is definitely the right way to go about it. Start off with the fact that the center of mass is 0 potential energy for both objects. You should be able to find a useful relationship between m_1, m_2, r_1 and r_2. Next you will probably want to compare the kinetic energy of the two...
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