Which quantity is increased in the step-down transformer?

A.)Current
B.)Voltage
C.)Power
D.)Frequency

Hint: Power equals voltage times current, a transformer transfers power from the primary coil to the secondary coil. In words, in a step –down transformer the voltage decreases and current is proportional. Generally, a transformer performs two functions; to increase low Ac voltages at high current (Step-up transformer) and to decrease high AC voltage at low current(Step-down transformer) in electric power application and for the coupling stage of the signal processing circuit.

Complete answer:
It converts high voltage, low current power into a low voltage, high current power, in short a step-down transformer reduces the output voltages. If a step-down transformer, voltage decreases corresponding current increases. There is a difference between step- transformer and step-down transformer; in step-up transformers have more number of turns in their secondary coils however, in step-down transformers it consist of more number of turns in their primary coil.

Step-down transformers are commonly used to convert the 220 volt electric found in most parts of the world to the 110 volts. Unfortunately, if the step-down transformer is used incorrectly it is very dangerous.

Therefore the option (A) is the right answer.

Note: If input supply is given on the low voltage winding, then it becomes a step-up transformer. Both step-up and step-down transformers use electromagnetic induction to convert voltage between two circuits. We can use both types in the distribution of power from supply station to end user.