# 4.1: Introduction to AC Circuits

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“AC” stands for Alternating Current, which can refer to either voltage or current that alternates in polarity or direction, respectively. These experiments are designed to introduce you to several important concepts specific to AC.

A convenient source of AC voltage is household wall-socket power, which presents significant shock hazard. In order to minimize this hazard while taking advantage of the convenience of this source of AC, a small power supply will be the first project, consisting of a transformer that steps the hazardous voltage (110 to 120 volts AC, RMS) down to 12 volts or less. The title of “power supply” is somewhat misleading. This device does not really act as a source or supply of power, but rather as a power converter, to reduce the hazardous voltage of wall-socket power to a much safer level.

This page titled 4.1: Introduction to AC Circuits is shared under a GNU Free Documentation License 1.3 license and was authored, remixed, and/or curated by Tony R. Kuphaldt (All About Circuits) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.