Answer:
A transformer is a device used in the power transmission of electric energy. The transmission current is AC. It is commonly used to increase or decrease the supply voltage without a change in the frequency of AC between circuits. The transformer works on basic principles of electromagnetic induction and mutual induction.
- Transformer works on the principle of mutual induction which is a special type of electromagnetic induction wherein a current change in primary coil induces a current in the secondary coil.
- A direct current(D.C) source provides a constant current that does not produce any change in magnetic flux.
- Thus if D.C. is used in the primary coil there will be no change in the magnetic flux linked with the secondary coil. As a consequence no emf will be induced in the secondary coil.
In brief, a transformer is a device that:
(a) transfer electric power from one circuit to another
(b) it does so without change of frequency and
(c) it accomplishes this by electromagnetic induction (or mutual inductance).
