What is the primary purpose of a circuit breaker?

The primary purpose of a circuit breaker is to interrupt current flow during overloads. This is crucial for protecting electrical circuits from damage caused by excessive current, which can result from faults such as short circuits or equipment malfunctions. When the current exceeds a predetermined level, the circuit breaker automatically disconnects the power supply, preventing potential hazards like overheating, fires, or damage to electrical devices.

In contrast, increasing voltage in a circuit is a function typically associated with transformers rather than circuit breakers. Providing a direct path for current is more related to conductors and wiring, which facilitate the flow of electricity. Measuring electrical resistance involves the use of specific instruments like ohmmeters, which is entirely different from the protective function that a circuit breaker serves in an electrical system.