What is the primary function of a circuit breaker?

The primary function of a circuit breaker is to prevent overheating, which is closely related to its role in protecting electrical circuits. Circuit breakers are essential safety devices designed to interrupt the flow of electrical current when it detects faults or overloads. When excessive current flows through a circuit, such as during a short circuit or when devices draw more power than the circuit can handle, the circuit breaker will trip. This interruption stops the flow of electricity, preventing potential overheating of wires and components that could lead to equipment damage, fires, or electric shock hazards. By functioning this way, circuit breakers ensure the safety and integrity of electrical systems.

Other choices do not align with the core purpose of a circuit breaker. For example, increasing voltage is typically the role of a transformer, while regulating current flow generally refers to devices that control or manage electrical flow. Providing resistance does not capture the essential protective function that circuit breakers serve in the electrical system.