Describe how the transformer converts 20kV to 300kV.

Here's how the transformer converts 20 kV to 300 kV:

1. An alternating current (a.c.) in the primary coil produces a continuously changing magnetic field.
2. This changing magnetic field is concentrated and guided by the soft iron core, linking it to the secondary coil.
3. According to Faraday's Law of Electromagnetic Induction, this changing magnetic flux through the secondary coil induces an electromotive force (e.m.f.) across its ends.
4. Since this is a step-up transformer, the secondary coil has significantly more turns than the primary coil, resulting in a higher induced voltage (300 kV) at the output compared to the input voltage (20 kV).