Circuit Quantities (Mod.3 Sect.1 Part 1) 1of 2

Resistance Devices

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• Legenda: Shown here are a few of the symbols for the many types of industrial resistance devices.

Resistance Analogy :O

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• The connection of a smaller diameter pipe to this water piping system has slowed and reduced the flow of water through the system. In a similar way, a resistor in an electric or electronic circuit restricts the flow of electricity through the circuit.
• Legenda: fascinating

Electron Flow

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• This figure shows the movement of current through a simple circuit. The power supply for the circuit is a battery. Note that the surplus of electrons at one end of the battery creates a negative charge, while a lack of electrons at the other end of the battery produces a positive charge. The end that has the surplus of electrons is the negative battery terminal; the end that has the lack of electrons is the positive battery terminal. The difference in potential between the two ends of the battery (that is, the opposing electrical charges) allows current to flow through the circuit.
• Legenda: Electrons move out of the negative battery terminal, flow through the wire in the circuit, and return to the positive battery terminal.