http://www.ck12.org Chapter 19. Electrical Circuits
CHAPTER
19 Electrical Circuits
Chapter Outline
19.1 Series Circuits
19.2 PARALLELCIRCUITS
19.3 COMBINEDSERIES-PARALLELCIRCUITS
19.4 AMMETERS ANDVOLTMETERS
19.5 REFERENCES
The string of Christmas lights on this tree may have cost $5 or $25, depending on how its circuit is constructed. One
possibility is that the lights are connected along a single path, in a series circuit. In this case, if the filament in one of
the bulbs were to burn out, then all the lights would go out. You wouldn’t be able to tell which one malfunctioned,
unless you go through the string and replace each bulb one at a time. The only advantage to such a design is that it is
inexpensive. Alternatively, each bulb could be placed in its own separate branch of the circuit. Since there are now
multiple paths by which charge can travel through the circuit, a burnt out bulb would not affect the rest of the lights,
and it’d be obvious which one would need to be replaced. Of course, a string of lights with this design, known as
a parallel circuit, would cost much more than the first. In this chapter, we will examine and learn the mathematics
involved in series circuits, parallel circuits, and those that are a combination of both.