EET 1150 banner

Unit 7: Series Circuits

In this unit you’ll begin learning how to analyze circuits. Circuit analysis means looking at a schematic diagram for a circuit and computing the voltage, current, or power for any component in that circuit. Closely related to the task of circuit analysis is the task of troubleshooting, which means figuring out what is wrong in a circuit that is not working correctly. Analyzing and troubleshooting go hand in hand; when a circuit is not working correctly, the easiest way to figure out what’s wrong is usually to measure voltages in the circuit and compare those measured values to the values that the voltages should have (which you compute by analyzing the circuit).

The rest of this course will concentrate on analyzing and troubleshooting resistive circuits (circuits that contain only resistors in addition to power supplies). In later courses you’ll learn how to analyze and troubleshoot circuits that contain other components, such as capacitors, inductors, diodes, and transistors.

This unit covers just about everything you could ever want to know about the simplest type of circuit, which is called a series resistive circuit.  Some of the things you’ll learn here apply only to series resistive circuits, but other things apply to any kind of circuit. For instance, the rule called Kirchhoff’s Voltage Law applies to all circuits, and is therefore a very important general rule of circuit analysis.

Unit 6 Review

Some Definitions
Connected Components
Series Connection
Series-Connected Components Have the Same Current
Series Path
Series Circuit

Current in a Series Circuit

Total Series Resistance
An Animated Lesson from our Friends in Wisconsin

Analyzing Series Resistive Circuits
An Example

Current Direction and Voltage Polarity
Voltage Drops and Voltage Rises

Voltage Sources in Series
Series-Aiding Voltage Sources
Series-Opposing Voltage Sources
Double-Subscript Notation for Voltages

Kirchhoff’s Voltage Law
KVL in Series Resistive Circuits
KVL in Other Circuits

Voltage Divider
The Voltage-Divider Rule
Potentiometer as a Voltage Divider

Power in a Series Circuit
Total Circuit Power

Voltage Relative to Ground

Open Circuit
Current Through an Open
Voltage Across an Open
Short Circuit
Voltage Across a Short
Current Through a Short
Typical Causes of Opens and Shorts

Unit 7 Review

Congratulations! You’ve completed the e-Lesson for this unit.