Constant DC voltage is required from a variable AC voltage. Which of the following is the correct order of operation?
A. Regulator, Filter, Rectifier
B. Rectifier, Regulator, Filter
C. Rectifier, Filter, Regulator
D. Filter, Regulator, Rectifier

Hint:The above problem can be solved by using the working principle and application of the Regulator, Filter and Rectifier. The rectifier converts the AC voltage to DC voltage, Filter removes the ripples from the DC voltage and regulator regulates the supply voltage.

Complete step by step answer:
The supply voltage used to provide the supply to electrical devices is alternating current supply. The devices used in the electronic circuit require constant DC voltage to avoid the fluctuations in the supply. There are many devices used for this purpose. Some of the devices that complete this process are Rectifier, Filter and regulator.

The variable supply AC voltage is converted into DC voltage by using the rectifier. The rectifier allows only supply of positive cycle and restricts the supply of negative cycle of the AC voltage.

The converted DC voltage from the rectifier consists of many ripples. These ripples create the non-uniformity in the DC voltage. The non-uniformity of the DC voltage is removed by using the filter circuit. The filter only allows the DC supply to pass from the filter circuit and restricts the AC component of the supply.

The filtered DC supply also consists of fluctuations in the supply. These fluctuations are regulated and controlled by the regulator. The regulator consists of the variable resistor that absorbs the excess supply and allows only rated supply.

The constant DC voltage is obtained by the processes rectification, filtering and regulation of the supply.
Therefore, the correct order of operation is rectifier, filter, regulator and the option (C) is the correct answer.

Note:Always remember the order of operation of conversion of variable AC supply to constant DC voltage. The order of operation is very important for the electronic devices because it prevents them from the fluctuations of supply and overheating.