Which of the following components helps in regulating voltage in an electrical system?

The component that helps regulate voltage in an electrical system is the transformer. Transformers operate on the principle of electromagnetic induction and are designed to either step up or step down voltage levels depending on the requirements of the electrical system. When AC voltage is applied to the primary winding of a transformer, it creates a magnetic field that induces a voltage in the secondary winding. By adjusting the turns ratio between the primary and secondary windings, transformers can effectively control the voltage levels within electrical circuits, ensuring that the voltage supplied matches the needs of various devices and systems.

Additionally, while other components such as capacitors and resistors play important roles in electrical systems (for instance, capacitors are often used for power factor correction and energy storage, and resistors control current flow), they do not primarily function to regulate voltage across the system like transformers do. Circuit breakers, on the other hand, are protective devices designed to interrupt current flow in the event of an overload or fault and are not responsible for voltage regulation. Thus, the transformer is the key component in maintaining proper voltage levels within an electrical system.