Superposition

Superposition is a good method to apply in analyzing circuits with multiple sources. The basic concept of this method is to analyze a circuit one source at a time. Using the Superposition Theorem, we remove all the independent sources, except one, and analyze that circuit for that one. Then we repeat the procedure for another source, and so on. Finally, the net result is found by summing all the single -source results. 

'Removing' Power Sources

If we have two voltage sources and we were to remove one source, and still have a complete circuit, we must replace the voltage source with a short circuit.

Source Transformation

In order to solve difficult and complicated circuits, it is important to simplify the given circuit for easier analysis. One way to simplify circuits is by Source Transformation. It is the process of using Ohm's Law to take an existing voltage source in series with a resistance, and replace it with a current source in parallel with the same resistance or vice-versa. This method can be applied to Thevenin's theorem and Norton's theorem.

Source Transformation for Independent Sources