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Question on internal resistance.

  1. Mar 12, 2013 #1
    I recently encountered circuits with the source having internal resistance, and it became confusing applying Kirchoff's Rules.

    What I did is this:

    assuming the loop is counter clockwise: -------wire - negative terminal +positive terminal
    (conventional flow)

    ---------- - + ----------------,
    I put : +(E- Ir) + (other IR's)

    ---------- + - ----------------,
    I put : -(E- Ir) + (other IR's)

    Is what I did correct? Also, can I treat the internal resistance as an external resistance?
  2. jcsd
  3. Mar 12, 2013 #2


    User Avatar

    Staff: Mentor

    Welcome to the PF.

    Unfortunately, the way that you posted your question is very confusing. I will move your thread to the EE forum, and I would like to please ask you to attach an image file of what you are asking.

    Source resistance is normally just shown/modeled as a series resistor connected to an ideal voltage source. Nothing more. Please post an attached image of what you are asking. Thank you.
  4. Mar 12, 2013 #3
    Adding to berkeman's post:


    That's how you do it.
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