What device in alternating current technology adjusts the voltage levels?

The device that adjusts the voltage levels in alternating current technology is the transformer. Transformers are designed to either step up or step down voltage levels while maintaining the same frequency, allowing for efficient transmission of electrical power over long distances. This capability is critical in electrical systems where varying voltage levels are necessary for different applications, such as in residential, commercial, and industrial settings.

Transformers work based on the principle of electromagnetic induction, where an alternating current in one coil induces a current in another coil. By varying the number of turns in each coil, transformers can achieve the desired voltage transformation. This process is essential for ensuring that electricity is delivered safely and effectively, as high voltages are often required for transmission over long distances, while lower voltages are needed for everyday use in homes and businesses.

Other options like rectifiers, capacitors, and generators play different roles in the electrical system. Rectifiers convert alternating current to direct current, capacitors store electrical energy, and generators convert mechanical energy into electrical energy. However, none of these functions specifically adjust voltage levels in the way transformers do.