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6: Direct-Current (DC) Resistor Circuits

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    100279
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    • 6.1: Introduction
      A direct-current (DC) circuit contains one or more complete paths for current to flow in a single direction.  In this chapter, we will learn how to analyze to analyze DC circuits consisting of resistors in series and parallel configurations.
    • 6.2: Source Voltage
      All voltage sources have two fundamental parts: a source of electrical energy that has a source voltage and an internal resistance. The source voltage is the work done per charge to keep the potential difference of a source constant. The source voltage is equal to the potential difference across the terminals when no current is flowing. The internal resistance of a voltage source affects the output voltage when a current flows. The voltage output of a device is called its terminal voltage.
    • 6.3: Resistors in Series and Parallel
      Basically, a resistor limits the flow of charge in a circuit and is an ohmic device where V=IR. Most circuits have more than one resistor. If several resistors are connected together and connected to a battery, the current supplied by the battery depends on the equivalent resistance of the circuit.
    • 6.4: Kirchhoff's Rules and Resistor Circuits
      Kirchhoff’s rules can be used to analyze any circuit, simple or complex. The simpler series and parallel connection rules are special cases of Kirchhoff’s rules. Kirchhoff’s first rule, also known as the junction rule, applies to the charge to a junction. Current is the flow of charge; thus, whatever charge flows into the junction must flow out. Kirchhoff’s second rule, also known as the loop rule, states that the voltage drop around a loop is zero.
    • 6.5: Application - Electrical Meters
      Voltmeters measure voltage, and ammeters measure current. Analog meters are based on the combination of a resistor and a galvanometer, a device that gives an analog reading of current or voltage. Digital meters are based on analog-to-digital converters and provide a discrete or digital measurement of the current or voltage. A voltmeter is placed in parallel with the voltage source to receive full voltage and must have a large resistance to limit its effect on the circuit. An ammeter is placed in
    • 6.6: Application - Grounding and Electrical Safety
      There are two known hazards of electricity—thermal and shock. A thermal hazard is one where excessive electric power causes undesired thermal effects, such as starting a fire in the wall of a house. A shock hazard occurs when electric current passes through a person. Shocks range in severity from painful, but otherwise harmless, to heart-stopping lethality. This section considers these hazards and the various factors affecting them in a quantitative manner.
    • 6.7: Direct-Current Circuits (Summary)
    • 6.8: Direct-Current Circuits (Exercise)
    • 6.9: Direct-Current Circuits (Answers)


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