Recent content by Bluestribute

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    Solving Spring System with RK4: Step-by-Step Guide

    So when you say acceleration is a function of position, are you saying F = ma = -kΔx (english language to math language is not my strong suit! Haha)? So would ak1 just be -kΔx/m? I think if I can get that relationship, I could figure out the implementation . . . I think
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    Solving Spring System with RK4: Step-by-Step Guide

    So in the example above, are you using the K values only on calculating acceleration? Then do you solve it like normal, or would you repeat that process for X and V, where V would be solved using K values? Cause the way I know it is that the K values are in the form h*f (where f is the multivar...
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    Solving Spring System with RK4: Step-by-Step Guide

    I'm not sure if this is the appropriate place, but I've just been searching, with no luck, on how to solve a spring system with RK4 (hence the math section, since it's a Runge Kutta question). How would you set it up to change position based on spring properties? I haven't really found any...
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    Blasius Model Solution in Matlab | Boundary Layer Profiles without ODE45

    I found this Matlab code: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Program: blasius % % Solve the Blasius problem % using 2nd order Runge-Kutta % % Mark Blyth 2007 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear all close all clc % Clears the command window %% % Set initial condition, step...
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    Blasius Model Solution in Matlab | Boundary Layer Profiles without ODE45

    . . . Possibly I have learned that? . . . So here's the equations for fj and gj we were given: gj = [∆η2/4][2gj+1/∆η2 + 2gj-1/∆η2 + fj([gj+1-gj-1]/2∆η)] fj = ∆η[fj-1/∆η + (gj+gj-1)/2] = fj-1 + ∆η(gj + gj-1) So to solve that, do I need to put in random initial guess to help iterate through...
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    Blasius Model Solution in Matlab | Boundary Layer Profiles without ODE45

    The B.C.'s we have are f(0) = 0, f'(0) = 0, and f'(∞) = 1, and that's directly relatable to η (so pretty much f(η), or at least that's what it looks like). I guess that math sort of confuses me than. I'm looking at this without much going on upstairs. I have a whole bunch of letters, like f and...
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    Blasius Model Solution in Matlab | Boundary Layer Profiles without ODE45

    Homework Statement Program, without any built in functions (like ODE45), a solution to the Blasius Equation in Matlab that outputs boundary layer profiles for given x values, u values, etc. Homework Equations 2f''' + f''f = 0 fj = fj-1 + Δη/2 * (gj + gj-1) gj = [Δη2/4][2gj+1/Δη2 + 2gj-1/Δη2 +...
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    Engineering Feedback Control: Modeling Mechanical System with Circuit

    So I'm going to do it the capacitance way just 'cause that's what we have in our lecture notes (the brief brief notes). I have the spring and mass 1 in series, and that series is in parallel with the second mass, which is in series with the current supply. So the laplace equations are something...
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    Engineering Feedback Control: Modeling Mechanical System with Circuit

    X2/Fin = (m1s^2 + k) / (m1m2s^4 + k(m1 + m2)s^2) is the transfer function they got
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    Engineering Feedback Control: Modeling Mechanical System with Circuit

    That's actually one of the website I used haha. So I guess now it's just making sure the circuit is correct. I have the force (current) in one loop that has the x2 node and m2 inductor. Then another loop which has the x2 and m2, a 1/k capacitor, and ends with an m1 inductor from the x1 node...
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    Engineering Feedback Control: Modeling Mechanical System with Circuit

    Homework Statement Find the transfer function for the following mechanical system with force input fin and output x2. Homework EquationsThe Attempt at a Solution The reason I left the equations blank is because I'm not sure how to appropriately model this scenario. I've seen two different...
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    Simple Electrical Modeling Question (w/ only C and L)

    Woopsie, right. LC Ok sweet, thanks. I just can't remember something we might have glossed over a few years ago . . . and no one recently has said "You can do this to a derivative". They just sort of do it on their own.
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    Simple Electrical Modeling Question (w/ only C and L)

    Homework Statement Find a differential equation that describes the circuit that includes only vin and vout as variables. Homework Equations C(dvin - dvout)/dt = i vin - vout = L(di/dt) The Attempt at a Solution So the answer I got was: C(d2vout/dt2) + vout = LC(d2vin/dt2) My question is...
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    Determine force of water on plate

    So are you saying the CS integral will simply be ρV2A, and the other term will be ρV(dv/dt). Since you said a rate of change. And I don't know how to relate explicitly density and velocity to force
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    Determine force of water on plate

    Homework Statement As water flows through the pipe at a velocity of 5 m/s, it encounters the orifice plate, which has a hole in its center. The pressure at A is 255 kPa , and at B it is 180 kPa, Assume water is ideal fluid, that is, incompressible and frictionless. Determine the force the water...
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