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27.2: Introduction

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    An electric circuit provides a complete path through which electrons may flow.  There are two basic types of circuits: series and parallel.  Devices in a series circuit are connected in one continuous loop while devices within a parallel circuit are connected in multiple loops.  A short circuit is a path of least resistance in the electrical circuit which bypasses the devices that the circuit is intended to operate.  When there is a short circuit, wiring may become hot.  Circuit diagrams show how the different types of circuits are connected together.  The lines in a circuit diagram represent wires.

    Figure \(\PageIndex{1}\): Series and Parallel Circuit. (

    The resistance is added differently in each type of circuit because of how current flows across each device in series versus parallel circuits.  

    Table \(\PageIndex{1}\): Series and Parallel Resistance

    Series Circuit Resistance

    Parallel Circuit Resistance

    \(R = R_1 + R_2 + R_3\)

    \(\dfrac {1}{R} =   \dfrac {1}{R_1} + \dfrac {1}{R_2} +\dfrac {1}{R_3}\)

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    27.2: Introduction is shared under a CC BY license and was authored, remixed, and/or curated by LibreTexts.

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