potentiometer

potentiometer. 1 Manually adjustable, variable, electrical resistor. It has a resistance element that is attached to the circuit by three contacts, or terminals. The ends of the resistance element are attached to two input voltage conductors of the circuit, and the third contact, attached to the output of the circuit, is usually a movable terminal that slides across the resistance element, effectively dividing it into two resistors. Since the position of the movable terminal determines what percentage of the input voltage will actually be applied to the circuit, the potentiometer can be used to vary the magnitude of the voltage; for this reason it is sometimes called a voltage divider. Typical uses of potentiometers are in radio volume controls and television brightness controls. 2 Device used to make a precise determination of the electromotive force, or maximum output voltage, of a cell or generator by comparing it with a known voltage.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.

More on potentiometer from Fact Monster:

  • voltage divider - voltage divider: voltage divider: see potentiometer.
  • Arnold O. Beckman - Arnold O. Beckman Born: 1900 Birthplace: Cullom, Ill. Apparatus for testing acidity—Beckman ...
  • voltmeter - voltmeter voltmeter, instrument used to measure differences of electric potential, commonly called ...
  • rheostat - rheostat rheostat , device whose resistance to electric current depends on the position of some ...
  • mixer - mixer mixer, either of two electronic devices in which two or more signals are combined. In the ...

See more Encyclopedia articles on: Electrical Engineering