What is the primary function of a resistor in an electrical circuit?

The primary function of a resistor in an electrical circuit is to limit the flow of current. Resistors are designed to provide resistance to the flow of electric current, which results in a reduction of the current that can pass through the circuit. This is crucial for protecting sensitive components within the circuit that may be damaged by excessive current.

Resistors operate according to Ohm's law, which states that the current flowing through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance. By adjusting the resistance value, engineers can control the amount of current that flows, thereby ensuring that the circuit operates safely and efficiently.

In contrast, other components may perform different functions: some store electrical energy, like capacitors, while others are designed to convert voltage, such as transformers, or measure electric potential, like voltmeters. Each of these functions is essential in its context, but the specific role of a resistor centers around managing current flow.