What is a variable resistor commonly known as?

A variable resistor is commonly known as a potentiometer because it is designed to adjust the resistance within a circuit, allowing for the control of voltage and current. Potentiometers are often used in applications where adjustable settings are needed, such as in volume controls for audio equipment or in various types of sensors.

The key function of a potentiometer is that it consists of three terminals: two are connected to a fixed resistance, while the third terminal is connected to a wiper that moves along the resistive path, varying the output voltage as it moves. This allows users to fine-tune the electrical characteristics of a circuit based on their needs, making potentiometers versatile components in electronic designs.

In contrast, capacitors store electrical energy in an electric field, inductors store energy in a magnetic field, and transformers are used for transferring electrical energy between two or more circuits through electromagnetic induction. None of these components provide the variable resistance functionality that a potentiometer does.