Question

Are transformers used in?
A. D.C circuits only
B. A.C circuits only
C. Both A.C and D.C circuits
D. Integrated circuits

Answer 1

Hint: Let us first get some idea about the A.C and D.C currents. Alternating Current (AC) is a type of electrical current in which the flow of electrons changes direction at regular intervals or cycles. Electrical current that flows in a single direction is known as direct current (DC).

Complete step-by-step solution:
A transformer is a passive component that transfers electrical energy from one circuit to another, or between multiple circuits. A changing current in any one transformer coil causes a changing magnetic flux in the core, which causes a changing electromotive force across all other coils winding around the same core. Without a metallic (conductive) link between the two circuits, electrical energy can be passed between them.
In electric power applications, transformers are typically used to increase low AC voltages at high current (a step-up transformer) or decrease high AC voltages at low current (a step-down transformer), as well as to link the stages of signal-processing circuits.
So option (b) is correct.

Note: Transformers do not transfer direct current (DC) and can be used to remove the DC voltage (constant voltage) from a signal while retaining the variable component (the AC voltage). Transformers are important in the electrical grid for changing voltages and reducing energy loss during transmission.