What does a transformer-rectifier do?

A transformer-rectifier is a device that is primarily used to convert alternating current (AC) into direct current (DC). The operation involves two key components: the transformer and the rectifier.

The transformer's role is to adjust the voltage level of the AC supply, either stepping it up or stepping it down, depending on the requirements of the circuit. This is an essential first step in ensuring the voltage is at an appropriate level for the rectification process.

After the transformation, the rectifier then converts this modified AC voltage to DC. This conversion typically occurs through diodes, which allow current to flow in one direction only, effectively blocking the negative part of the AC waveform. As a result, the output is a unidirectional current, which is the key characteristic of direct current.

In this context, the other answers do not describe the function of a transformer-rectifier accurately. Generating alternating current does not align with the device's purpose since it is focused on converting AC. While supplying power to the primary coil is a function of the transformer itself, it does not encapsulate the transformer-rectifier's primary function. Providing a bridge for electrical circuits might refer to certain circuit configurations, but it does not specifically match the transformer-