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Homework Help: Simple Electricity Question

  1. Jan 17, 2008 #1
    Hi, I'm doing an introductory electrical engineering course on my own and so far have gotten a few pages into the book. I understand pretty much all the problems so far except for this one.
    "The charge entering a terminal of an element is given by the equation
    Code (Text):
    q(t) = (k1)t^2+(k2)t
    Where 1 and 2 are subscripts.
    If i(0) = -5 A and i(1)=+5A, find k1 and k2."

    I think you have to use the integral of i(t) which gives q(t) but I'm not sure how to start. Any help would be appreciated.
  2. jcsd
  3. Jan 17, 2008 #2


    User Avatar

    Staff: Mentor

    Not the integral of i(t), instead start with this basic equation:

    [tex]i = \frac{dq}{dt}[/tex]
  4. Jan 22, 2008 #3
  5. Jan 23, 2008 #4
    Just a note to the OP, such type of solving for constants can be seen in solving particular solutions for differential equations and Fourier series (if you take it a step ahead.) Just something to remember, so that when you actually see it later on, it'll be a piece of cake.
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