For what reason might a fixed resistor be used in a circuit?

A fixed resistor is used in a circuit primarily to provide constant resistance. This means that its resistance value does not change with varying voltage or current conditions, making it essential for controlling and limiting the flow of electric current in the circuit. By maintaining a steady resistance, it helps to ensure the proper functioning of other components within the circuit, such as protecting sensitive parts from excessive current.

The role of a fixed resistor is crucial in applications where consistent performance is required, such as in biasing of transistors, setting gain levels in amplifiers, or creating voltage dividers. In contrast to variable resistors that can be adjusted, fixed resistors are reliable for maintaining a specific resistance regardless of external changes, thus providing stability in electronic circuits.