Question

How does a transformer work ?

Answer 1

A transformer needs an alternative current that will create a changing magnetic field.. An alternative current will be passing through primary coil wrapped around a soft iron core. Changing current produces changing magnetic field. This induces an alternative voltage in a secondary coil

Answer 2

A transformer needs an alternating current that will create a changing magnetic field. ... An alternating current passes through a primary coil wrapped around a soft iron core. The changing current produces a changing magnetic field. This induces an alternating voltage in the secondary coil.