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Homework Help: Find the transfer function

  1. May 16, 2010 #1
    1. The problem statement, all variables and given/known data
    find the transfer function H(s)
    [PLAIN]http://img192.imageshack.us/img192/4204/asdwoe.jpg [Broken]

    2. Relevant equations
    H(s) = Vout/Vin
    done in the frequency domain so: C1 and C2 turns into 1/sC
    where C1 = C2 = .1F
    and R1 = R2 = 20

    3. The attempt at a solution
    to find the transfer function, i have to apply an impulse source. therefore, Vin is just 1V.
    my attempt at this by using node voltage method:
    (Vx is the node that connects R1, R2, and C2)

    (Vx -1)/20 + Vx/(10/s) + (Vx - Vout)/20 = 0

    i am stuck with two unknowns and 1 equation. :[
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. May 16, 2010 #2
    bump, anyone?
  4. May 16, 2010 #3

    The Electrician

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    Gold Member

    Write another equation, then you'll have 2 equations and 2 unknowns. I would write one at the output node.
    Last edited by a moderator: May 4, 2017
  5. May 17, 2010 #4


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    The difference between the voltages of the output and input nodes is the voltage across C1 and also the sum of the voltages across R1 and R2.
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