Question

A 100% efficient transformer has 25 turns in the primary and 125 turns in its secondary coil. If the current in the secondary coil is 2 a, then the current in the primary coil is

Answer 1

We can step the voltage down from a high voltage to a smaller one or we can step it up. The principles are the same. A transformer has two coils - a primary coil and a secondary coil. An alternating current flows in the primary coil and this induces a voltage in the secondary coil.