Answer / thowsif_emerson

A potentiometer is a manually adjustable resistor. The way
this device works is relatively simple. One terminal of the
potentiometer is connected to a power source. Another is
hooked up to ground (a point with no voltage or resistance
and which serves as a neutral reference point), while the
third terminal runs across a strip of resistive material.
This resistive strip generally has a low resistance at one
end; its resistance gradually increases to a maximum
resistance at the other end. The third terminal serves as
the connection between the power source and ground, and is
usually interfaced to the user by means of a knob or lever.
The user can adjust the position of the third terminal
along the resistive strip in order to manually increase or
decrease resistance. By controlling resistance, a
potentiometer can determine how much current flows through
a circuit. When used to regulate current, the potentiometer
is limited by the maximum resistivity of the strip.


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