• Know how a non-ideal source consisting of an ideal voltage source and a series resistor can be transformed into a current source and a parallel (or shunt) resistor.
• Know what happens to the power consumed in a circuit when a source transformation is made.
• Understand what is meant by statements such as "the two (non-ideal) sources are equivalent at the pair of terminals a-b."
• Know the form for a Thevenin equivalent and a Norton equivalent circuit.
• Know the relation that exists between R_Th, V_Th and i_sc.
• Know how to use a Thevenin or Norton equivalent circuit as an analysis tool.
• Learn what circuit properties are equivalent between a Thevenin equivalent and the original circuit from which it was derived, and what things are not equivalent.
• Know the conditions under which maximum power is transferred between a Thevenin equivalent circuit and a load resistance.
• Understand what the principle of superposition is, and how it applies to linear circuits.
• Know how to deactivate voltage and current sources when applying superposition.

Skills: In studying the material in these sections, you should make certain that you develop the following skills:

• Be able to transform a non-ideal source consisting of an ideal voltage source and a series resistor to one with an ideal current source and a parallel resistor and vice-versa.
• Be able to derive a Thevenin equivalent circuit from a Norton one and vice-versa.
• Be able to derive a Thevenin or Norton equivalent circuit using a test voltage or a test current source.
• Be able to find the value of a load resistor which will have the maximum power transferred to it from a given circuit consisting of resistors, independent and dependent sources.
• Be able to analyze a circuit with more than one independent source by making separate analyses for each source (with the others deactivated).

Review Questions: Test your understanding of the material in these sections by answering the following review questions:

1. Make up a simple circuit consisting only of resistors and dependent sources and find the Thevenin and Norton equivalent circuits for it. Can you explain the result? Is it a general result? Are there any exceptions?

2. A circuit consists of resistors and dependent and independent sources. At the terminals where a Thevenin equivalent circuit is to be found, there is an independent voltage source connected. What will be the form of the Thevenin and Norton equivalent circuits.

3. Design a simple circuit consisting of a Thevenin equivalent circuit and a load resistor. Allow the value of the load resistor to vary over the range from R_Th/10 to 10 R_Th. Find the corresponding variations in the power supplied by the voltage source, the power dissipated in the Thevenin resistor, and the power dissipated in the load resistor.