Question

The core of a two winding transformer is subjected to magnetic flux

Answer 1

The purpose of a tap changer is to regulate the output voltage of a transformer. It does this by altering the number of turns in one winding and thereby changing the turns ratio of the transformer. There are two types of transformer tap changers: an on-load tap changer (OLTC) and a deenergised tap changer (DETC). Note that not all transformers have tap changers.

Answer 2

Explanation:

The Two-Winding Transformer. The two-winding transformer is one in which two windings are linked by a common time-varying magnetic flux. ... However, in iron-core transformers a given winding must operate at a voltage that does not exceed its rated value at rated frequency - otherwise the exciting current becomes excessive ...