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2: Electrical Components and Circuits

  • Page ID
    332625
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    • 2.1: Basic Terminology and Laws of Electricity
      Current, \(I\), is a movement of charge over time and is expressed in amperes, \(A\), where 1 ampere is equivalent to 1 coulomb/sec. In this section we review the convention used to describe currents in electrical circuits and review four laws of electricity.
    • 2.2: Direct Current (DC) Circuits
      A direct current, which is the focus of this section, is one that flows in one direction. There are two basic direct current circuits of importance to us: those with two or more resistors connected in a series, and those with two or more resistors arranged parallel to each other. Other direct current circuits can be understood in terms of these two basic circuits.
    • 2.3: Alternating Current Circuits
      A direct current has a fixed value that is independent of time. An alternating current, on the other hand, has a value that changes with time. This change in current follows a pattern that we can characterize by it period—the time for one complete cycle—or by its frequency, which is the reciprocal of its period. Frequency is reported in hertz (Hz), which is equivalent to one cycle per second.
    • 2.4: Semiconductors
      A semiconductor is a material whose resistivity to the movement of charge falls somewhere between that of a conductor, through which we can move a charge easily, and an insulator, which resists the movement of charge. Some semiconductors are elemental, such as silicon and germanium (both of which we examine more closely in this section) and some are multielemental, such as silicon carbide.


    This page titled 2: Electrical Components and Circuits is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by David Harvey.

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