potentiometer

electrical instrument

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Last updated

June 17, 2026

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A potentiometer is an electrical instrument used for measuring electromotive forces or potential differences. It functions as a voltage divider. A more common type of potentiometer is a resistor with three terminals: two fixed and one connected to a variable contact arm. This is often used for purposes like volume control in audio equipment.12

A related device is a rheostat, which is an adjustable resistor used to regulate current or vary resistance in an electric circuit. Rheostats can control generator characteristics, dim lights, and manage motor speeds.23

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resistor
…may be called rheostats, or potentiometers.
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…may be called rheostats, or potentiometers.
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rheostat
…type of rheostat is the potentiometer, an instrument that measures an unknown voltage or potential difference by balancing it, wholly or in part, by a known potential difference. A more-common potentiometer is simply a resistor with two fixed terminals and a third terminal connected to a variable contact arm; it…
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…type of rheostat is the potentiometer, an instrument that measures an unknown voltage or potential difference by balancing it, wholly or in part, by a known potential difference. A more-common potentiometer is simply a resistor with two fixed terminals and a third terminal connected to a variable contact arm; it…
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voltmeter
The potentiometer operates by comparing the voltage to be measured with known voltage; it is used to measure very low voltages. The electronic voltmeter uses amplification or rectification (or both) to measure either alternating- or direct-current voltages. The current needed to actuate the meter movement is…
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The potentiometer operates by comparing the voltage to be measured with known voltage; it is used to measure very low voltages. The electronic voltmeter uses amplification or rectification (or both) to measure either alternating- or direct-current voltages. The current needed to actuate the meter movement is…
Read More