In this chapter, we introduce the first of three simple
circuit elements that can be connected with wires to form
an electric circuit. Electric circuits are the basis for the vast
majority of the devices used in our society. Here we shall
discuss capacitors, devices that store electric charge. This discussion
is followed by the study of resistors in Chapter 27 and
inductors in Chapter 32. In later chapters, we will study more
sophisticated circuit elements such as diodes and transistors.
Capacitors are commonly used in a variety of electric circuits.
For instance, they are used to tune the frequency of
radio receivers, as filters in power supplies, to eliminate sparking
in automobile ignition systems, and as energy-storing