Source Transformation

Source Transformation

The circuits in this set of problems consist of independent sources, resistors and a meter. In
particular, these circuits do not contain dependent sources. Each of this circuits has a series-parallel structure that makes it possible to to simplify the circuit by repeatedly

• Performing source transformations.
• Replacing series or parallel resistors by an equivalent resistor.
• Replacing series voltage sources by an equivalent voltage source.
• Replacing parallel current sources by an equivalent source source.

Each simplification is done in such a way that the voltage or current measured by the meter is not
disturbed. Generally, that requires beginning the simplification at the opposite end of the circuit
from the meter and then working toward the meter.

Example 1:
Consider the circuit shown in Figure 1. Find the value of the voltage measured by the voltmeter

Solution: The voltmeter measures the voltage across the current source. (The color-coded probes 

of the voltmeter indicate the reference direction of the voltage measured by the voltmeter.) 

Figure 2 shows the circuit after the replacing the voltmeter by the equivalent open circuit and 

adding a label to show the voltage measured by the meter. 

Figures 3 through 17 illustrate the use of source transformations and equivalent resistances to 

simplify the circuit.