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Homework Help: Circuit Analysis problem

  1. Sep 30, 2016 #1
    • ✱✱ member reminded to use the 3-header homework template provided ✱✱
    There is a question I am not sure of how I should start/approach. Any help would be appreciated, thanks.

    Vc(0)=3V and ic(t)=e^-50t for t>0 and t=0. Find the value of R and voltage v(t) for t>0 and t=0

    Attached Files:

  2. jcsd
  3. Sep 30, 2016 #2
    Apply Kirchhoff' Voltage rule in the two loops ,
    first in the loop with 2 ohm resis. and capacitor to find voltage
    and then in the loop with 2 resistors (R and 2 ohm) to find R !
  4. Sep 30, 2016 #3


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    Staff: Mentor

    I might start by examining the form of the capacitor current. There's a time constant that will have to involve the value of R in some way... Are you familiar with Thevenin equivalents? What resistance will the capacitor "see" when it's following ic(t)=e^-50t ? Can you disentangle R from that?
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