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RL circuit natural response

  1. Jun 12, 2006 #1
    Can anyone please help me slove this example circuit i found.
    im having a hard time finding the initial current through the inductor and duno how to deal with the dependent source and inductor after the switch is opened.

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    Last edited: Jun 12, 2006
  2. jcsd
  3. Jun 12, 2006 #2


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    Staff: Mentor

    What's the diamond shaped thing? Is that a current controlled voltage source or a current controlled current source?

    What equations have you been able to set up so far? Is this a homework problem?
  4. Jun 13, 2006 #3
    Looks like a current controlled voltage source.

    To the OP -- you're going to have to show some work, like berkeman said.
  5. Jun 15, 2006 #4
    thanks for feed back but i have figured it out. If anyone else needs help with this circuit i'll get u guys started. to find initial current at t=0- the inductor is a short circuit so Io is just the current through the 4.5Ohm resistor.

    After the switch is closed to find iL(t) for t >=0 you will need to use the natural response equation for the current of an inductor which means u will need to find Req for tao. to find Req u need to thevenize the circuit by creating an open circuit at the inductor and finding Voc=Vth then the R in the standard form would be Vth/Itotal.
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