What is the primary function of a transformer?

The primary function of a transformer is to adjust voltage levels in an electrical circuit. Transformers operate on the principle of electromagnetic induction, allowing them to convert alternating current (AC) from one voltage level to another. This is crucial in electrical power distribution systems, where voltage levels must be stepped up for efficient transmission over long distances and then stepped down for safe use in homes and businesses.

By manipulating the number of turns in the primary and secondary coils, transformers can effectively increase or decrease voltage, maintaining power, and ensuring it can be delivered efficiently. This role is essential for reducing energy loss during transmission and ensuring that the right voltage reaches end users.

The other options discuss functions that do not align with what transformers do. For instance, a transformer does not increase current flow but rather alters voltage and the relationship between current and voltage is governed by the transformer’s design and the load it is supplying. Measuring resistance is not a function of transformers; that is more aligned with measuring devices like ohmmeters. Similarly, while transformers can indeed help in reducing harmonics or electrical noise indirectly, their primary purpose is not filtering, making voltage adjustment their key function.