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RL Circuit

  1. Mar 13, 2010 #1
    I am trying to analyse an RL circuit, particulartly the dependence of current in 2 resistors with time, in an RL circuit. This is what I think but I would really love some people to tell me if I am getting it wrong or if there is anything they want to add to it.

    ***Just after the the switched at t = 0, the voltage in R1 is the same as the voltage in R2 because they are in parallel. Therefore the current in R1 is: I = E/R1 which is the maximum current. But the current in R2 is zero because current in the inductor is zero at t = 0.

    Do I have a good reasoning for the current in the resistor R2 being zero at t = 0?

    ***A long time after the switched is closed: I think as time goes to infiniti, the current in R1 drops down from maximum (E/R1) to zero.
    The current in R2 starts growing exponentially as time increases. And at some point the current in R2 goes steady or reach equilibrium(not growing and not decaying).

    Question: Is it true that the current in R1 decays to zero as time goes to infiniti? I am not sure the current in R1 decays though because the resistor does not consume current.

    I would like some help analysing this circuit. It looks pretty interesting.

    Thanks, Momodou

    Attached Files:

  2. jcsd
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