Recent content by rsnd

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    Complex Algebra Help: Finding u(x,y) & Proving Result

    Homework Statement I am told: {\frac {{\it du}}{{\it dx}}}=y and {\frac {{\it du}}{{\it dy}}}=x. Need to find u(x,y) which is a real valued function and prove the result. Homework Equations The Attempt at a Solution Well, I think the answer is of the form u(x,y) = xy + c because...
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    Deriving inverse tans from complex product?

    And here I thought I'd never have to multiply the hard way after learning the polar form. Thanks heaps again =)
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    Deriving inverse tans from complex product?

    I am supposed to derive 4\,\arctan \left( 1/5 \right) -\arctan \left( {\frac {1}{239}} \right) from the complex product of \left( 1+i \right) \left( 5-i \right) ^{4} I do see how the argument of product of the complex expression is equal to pi/4 - 4 arctan(1/5) but I am totally lost. SO how...
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    Medical How fast can our brain respond?

    become aware of change?
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    Medical How fast can our brain respond?

    0.01 us? 1 ms? 2 ms? 5 ms? 7 ms? 10 ms? 20 ms? 40 ms? 80 ms? 160 ms? 250 ms? 500 ms? 1000 ms? lol
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    How Can I Efficiently Read Multiple Resistor Values for Temperature Mapping?

    Well, Ideally I should be reading 1 value at a time because 4 varisters at once tends to increase the values read inside. Anyways... Is it possible doing it through a demultiplexer...if I have the input as +5v or something and then use parallel port output bits to set a perticular channel...
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    How Can I Efficiently Read Multiple Resistor Values for Temperature Mapping?

    well...I have 14 varisters equally distributed on the walls of my room(FCC Structure) which will produce specific resistances depending on the temperature on that place. And my program is to read those resistance values and convert them into temperatures. Then it is to apply larplace's...
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    Simple absolute value problem with inequalities

    hehe...how did you get |x-a|<d => |x-a|=e|\sqrt{x}+\sqrt{a}|? I think it should be |x-a|<d => |x-a|<e|\sqrt{x}+\sqrt{a}|
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    How does battery chargers work?

    Well...thats a lot of current you are talking about! Please fix me up if i am wrong or there is a better way of looking at it! So It would not matter about what current/voltage I input to the charger, as long as I input a fare amount of each over time to make up for the energy I am trying to...
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    How does battery chargers work?

    :bugeye:Hmm...how about AC batteries? e.g. If I wanted to store energy directly from an AC generator which is to act as a battery charger? Thanks
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    Help: Generating AC with Hand-Driven Generator

    kool...farady's laws...flux and stuff...coil l in mgf B etc...its all coming back...just another question on that... If I was to store X joules of energy from it to a battery? how would I do it?
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    How does battery chargers work?

    I mean do you input a lot of current and it has some sort of capacitor in it to sotore the charge? any links I can make use of? Thanks heaps
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    Help: Generating AC with Hand-Driven Generator

    Hello I am supposed to design a hand driven AC generator. I kinda know how to do it. You just have some sort of coil and you rotate it in a magnetic field. Thats all good but for analysis part I am required to give specific information information about no of loops of the coil and total...
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    If f(c) = infinity and c is in [a,b]

    nice...I just invented the mean value theorom!
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