Circuit Theory/Thevenin-Norton

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Vth using Node[edit]

opening load, finding Vth using Node .. code

In using Node[edit]

shorting load, finding In using Node .. code

Rth or Rn[edit]

Finding Rth using source injection and node[edit]

Here is the mupad/matlab code that generates the answer Rth = 6.0591 ohms.

Comparing Node with Thevenin Equivalent[edit]

solving using Node .. code
solving using Thevenin equivalent

Solving the node equations yields:

Using the Thevenin equivalent (and voltage divider) to compute voltage across the 12 ohm resistor:

So they match ...

Thevenin voltage and resistance can not be computed from a node analysis of the entire circuit, but the node analysis of the entire circuit can be used to check if the thevenin equivalent produces the same numbers.