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    Need Some Metal Sheet Advice

    I am working on a project, all details can be found http://www.overclockers.com/forums/showthread.php?t=680115" is the catalog page with the options. I've googled about annealed and "dead soft" however I still can't tell exactly how soft/flexible it is. All I need it to support is water running...
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    Invertible Matrix Question

    Homework Statement Find all n x n-matrices A such that Q-1 A Q = A for all invertible n x n matrices Q. Homework Equations None The Attempt at a Solution Proof by induction Assumption: True for A = k(In) where k is a real number Base case: k = 1 When k =1 A = 1 * In...
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    Buy or make magnesium (local only)

    We have a fisher scientific locally, but they want $40+ for 100-300g of magnesium. An idea I was told about was to use magnesium oxide, which you can get from any nutrition place, such as a GNC. Mix it with hydocloric acid, to form MgCl + H20, then use electrolysis with carbon electrodes, to...
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    Buy or make magnesium (local only)

    Hey guys, I'm on a bit of a time crunch here, I have to have everything buy Wednesday (10/27). I've been asked to give a presentation on food in the classroom at a meeting on Wednesday. What I normally like to do is a demonstration involving a Flameless heater. I just use the same technique...
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    System of Differential Equations

    Thank you for leading me down the right path! I got it now :) The solution was y(t) = (5/2)e^(-4t)+(-3/2)e^(4t) x(t) =(5/2)e^(-4t)-(-3/2)e^(4t)
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    System of Differential Equations

    Ah ok, I see. Now I get \frac{-1}{4}\frac{d^2y}{dt^2} = -4y \frac{-1}{4}\frac{d^2y}{dt^2} +4y = 0 so, \frac{-1}{4}r^2 + 4y = 0 y(t) = C1 e^(4t) + C2e^(-4t) Now doing the same for x(t), I end up with the same equation of x(t) = C1 e^(4t) + C2e^(-4t), however given my initial...
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    System of Differential Equations

    Homework Statement So my friend asked me for help because he assumed having a math degree meant I knew math :rolleyes: [PLAIN]http://courses.webwork.maa.org:8080/wwtmp/equations/0e/c5a05957810916cfdff379ee0642fc1.png [Broken] (dx/dt=−4y and dy/dt = −4x) Convert this system to a...
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    Charge Density

    Yes and no. You are talking about MHD propulsion, while I am talking about a generator to produce electricity. Same principles, but by no means do I supply the amps. The amps are created by the flow/movement of the fluid. Not the movement by the amps (which is what you are talking about). When...
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    Charge Density

    Interesting, thanks for the link, it's quite detailed so I'm going to take my time reading through it. I guess I should explain to you exactly what I'm trying to figure out. What I want is to find the amperage of a flowing fluid. As long as there is a net charge in said fluid, and the fluid is...
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    Charge Density

    Yes those are the units (expect I'm using meter not cm, but thats not overly important). For the fluid, seawater, brack/brine water, tap water. I guess maybe it's not as generic as I though, in terms of the equation and charge density in general. I'm looking at liquids specifically.
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    Charge Density

    No one?
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    Charge Density

    I need to find amps, so it's really all or nothing for that equation. Without the charge density, I'm left with Coulomb * m2 * m/s = Coulomb m3/s or Amp * m3. I need the charge density. As for the fluid, well I'm looking for how to find the change density for generic purposes. I don't have a...
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    Charge Density

    Is this the wrong forum? Should I ask for it to be moved? I really wasn't 100% sure what forum this belonged in but I figured EE would cover it.
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    Charge Density

    How would one determine the charge density of a fluid? I'm using the equation of I = qnvA . Amperes = charge of electron * charge density * velocity * Area. The only thing I'm not sure of is how to determine charge density. I've read several websites and I have a few textbooks here...
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    How to find the Atomic Structure of a Constituent

    I got it from a textbook I have. The section talks about tachmen and uses a Tortoises-Hares fable to explain it. Really crummy section, the rest of the book is okay. So I was just going off of the one sentence I quoted below...
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    How to find the Atomic Structure of a Constituent

    H2O is neutral, but with all the ions in the water, there has to be something. Even an insignificant amount would still mean something to me.
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    How to find the Atomic Structure of a Constituent

    For a project/idea I'm working on, I need to find the charge density of tap water. I've read that this can be determined by simply subtracting total protons minus total electrons. I've got a list of elements that are in the water, but I'm not 100% sure how to find the exact number of electrons...
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    Losing Valence Electrons

    So I've read through https://www.physicsforums.com/showthread.php?t=32409" thread on valence electrons but it doesn't really answer my question. I think I am in the right forum, I was debating between here and chemistry but it deals more with atoms. What I want to know is this: How do I...
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    Increasing voltage, from millivolts to 120volts

    I'm working on a Magnetohydrodynamics generator. It's DC because my magnetic field doesn't change and the fluid flows through the magnetic field in one direction, those only causing voltage in one direction. I have some ideas involving multiple magnets and generating an AC current that way but...
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    Increasing voltage, from millivolts to 120volts

    I'm working on a design for a certain kind of generator. My main issue is that based on how the generator works and the circumstances in which I am designing it for, I end up with the problem of having very little voltage but a whole lot of amps. My theoretical/ideal voltage is .065v, and my...
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    Finding Charge Density of Solution and then Amps

    So it seems one of my errors was in using Faraday's constant. That assumed that all electrons counted, but in reality on the valence electrons are what matter in terms of electricity. Now redoing my calculations, and to make it simple I'll only use 1 Chloride ion. A Chloride ion has 8...
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    Finding Charge Density of Solution and then Amps

    Alright, I'm working on an idea for a MHD generator, and I have a water based solution. That is Cl- 6250 mg/L or 176 mmol/L SO4^2- 6250 mg/L or 65 mmol/L Na+ 6250 mg/L or 272 mmol/L K+ 6250 mg/L or 160 mmol/L Ca^2+ 5000 mg/L or 125 mmol/L If I'm doing my math right, that means my...
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    Electrical Conductivity of Fluids

    So it has always been my understanding that in order for something to electrically conductive it has to have more electrons than it needs. If the electrons can be easily shaken from their atoms, then it's conductive. The easier it is for the electron to move to the next atom the more conductive...
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    Ion Exchange of NaCl from H2O

    I understood the bases for ion exchange though to be passive not requiring any energy (from the outside) for the actual exchange. It's simply diffusion of the atoms. Correct me if I am wrong, but thinking back to the biology classes I've taken, and I remember that the kidney and I believe it was...
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    Ion Exchange of NaCl from H2O

    Leaving the physics out of this, I'm working on an idea for an in home MHD generator. I'm trying to figure out a conductive fluid to use. I'm back to the idea of salt water, or H20 + NaCl. I know this is a very conductive solution, but I'm no chemist. What I plan to do is put a MHD generator and...
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    Siemens CompetitionMHD Generator

    etherpulse, I gladly will post up my information as I get it. xez thanks for information again. So here is where I am at. I need a solution still. I've tried IPA solution (91% IPA, 9% water) + NaCl solution. It was no good. I could not get a reading above 50 milivolts with it. I also...
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    Siemens CompetitionMHD Generator

    Ok I've gone through two designs and I'm on my second test model. Here is my current issue. Salt water doesn't work. at least I don't think. I got a reading of 1.5volts off of it, but I had bigger issues. I have wires comeing out of my generator to measure the voltage on. Well on one set...
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    Conductive liquids

    Well, I ran into a huge issue. I forgot about a little thing called electrolysis. I'll recap what happened today. I've got my 3rd revision of my experiment underway, this one is made up of CPVC and one piece of copper piping. I heat the whole experiment up via the copper piping, and the hot...
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    Conductive liquids

    Calcium Chloride. That sounds like a good solution. Its 50% more conductive than regular salt water!
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    Conductive liquids

    Ionic liquids would be great. They are full of electrical charge, which is what I need.
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