# CHAPTER 3

*Resistive Circuits*

**IN THIS CHAPTER**

**3.1** Introduction

**3.2** Kirchhoff's Laws

**3.3** Series Resistors and Voltage Division

**3.4** Parallel Resistors and Current Division

**3.5** Series Voltage Sources and Parallel Current Sources

**3.6** Circuit Analysis

**3.7** Analyzing Resistive Circuits Using MATLAB

**3.8** How Can We Check …?

**3.9 DESIGN EXAMPLE**—Adjustable Voltage Source

**3.10** Summary

Problems

Design Problems

**3.1 ***Introduction*

In this chapter, we will do the following:

- Write equations using Kirchhoff's laws.
Not surprisingly, the behavior of an electric circuit is determined both by the types of elements that comprise the circuit and by the way those elements are connected together. The constitutive equations describe the elements themselves, and Kirchhoff's laws describe the way the elements are connected to each other to form the circuit.

- Analyze simple electric circuits, using only Kirchhoff's laws and the constitutive equations of the circuit elements.
- Analyze two very common circuit configurations: series resistors and parallel resistors.
We will see that series resistors act like a “voltage divider,” and parallel resistors act like a “current divider.” Also, series resistors and parallel resistors provide our first examples of an “equivalent circuit.” Figure 3.1-1 illustrates this important concept. Here, a circuit has been partitioned into two parts, *A* and *B*. Replacing *B* by an equivalent ...