A power supply serves as both a rectifier and transformer to convert AC house current to DC and to step down voltage from 110 V or 220 V to 50, 30, or 20 volts.

True

Explanation:

A computer can be defined as an electronic device that is capable of receiving of data in its raw form as input and processes these data into information that could be used by an end user.

Generally, a computer is composed of five (5) main components and these include;

I. Input unit.

II. Output unit.

III. Central processing unit (CPU).

IV. Storage (memory) unit.

V. Power supply unit (PSU).

A power supply also referred to as power supply unit (PSU) can be defined as a hardware component of a computer that converts and step-down the domestic alternating current (AC) electrical power to a low-voltage regulated direct current (DC) power, so that the internal components of a computer can be supplied with power.

Hence, the power supply unit (PSU) serves as a rectifier by converting alternating current (AC) house current to direct current (DC) and as a transformer to step-down voltage from 220 Volts or 110 Volts to 50, 30, or 20 Volts depending on the requirements of a computer.