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Homework Help: Thevenin's Theorem

  1. Jan 15, 2006 #1
    ok i need a little bit of help understanding this, I've read over it ten times and it still is making no sense to me

    "a given network, with constant voltages and resistance produces a current flow in the load resistor equal to that which flows if the load resistor were applied across an equivalent circuit which has a) an internal resistnace measured at the terminals of the circiut with the voltage source replaced by its equivalent internal resistance; b)a vltage at the termainlas equal to that existing in the original circiut after removal of the load resistor"

    like i said I've read it ten times and Im still pulling nothing from it so if anyone could explain this in simpler terms it would be greatly appreciated.
  2. jcsd
  3. Jan 15, 2006 #2
    The whole point of thevenin theorem is analyze a load resistor within a complicated circuit.

    It turns out however, that a glob of voltage/current sources, and resistors interconnected together along with a load resistor can be reduced to 1 voltage source (thevenin) and 1 special resistor (thevenin resistor).

    And if you connect in series the thevenin voltage source with thevenin resistor and your load resistor it will be the same as if your load resistor was connected to the original complicated circuit.
  4. Jan 16, 2006 #3


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    Check out http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-002Circuits-and-ElectronicsFall2000/VideoLectures/index.htm [Broken].

    Check them all out if you have the time. The teacher is awesome and funny.
    Last edited by a moderator: May 2, 2017
  5. Jan 18, 2006 #4
    You can think of a Thevenin equivalent circuit as just the total voltage of a circuit. Imagine looking in from the outside - you don't care WHERE the voltage comes from; you just want the total number value. This can be found usually by a voltage divider across a load resistor which is placed at the circuits output terminals.

    That's what that description is trying to say.
  6. Jan 18, 2006 #5
    Thanks a lot for the info and the link, so far it looks very informative but i think i will need to get a little more understanding befire i can fully grasp most of that stuff.
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