Explanation:

A transformer is a static electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. It consists of two or more coils of wire, known as windings, which are wound around a common magnetic core.

In a transformer, the primary winding is the coil that receives electrical energy from the input source, while the secondary winding is the coil that delivers the transformed electrical energy to the load. The primary winding is typically connected to the high voltage side, and the secondary winding is connected to the low voltage side.

Factors affecting cross-sectional area:

The cross-sectional area of a winding in a transformer depends on several factors, including the voltage rating, current rating, and the desired level of magnetic flux density.

High voltage winding:
The high voltage winding, also known as the primary winding, is designed to handle high voltages. As the name suggests, it is connected to the high voltage side of the transformer. The primary winding has fewer turns compared to the secondary winding, as it is designed to step down the high voltage to a lower voltage suitable for the load. Since the voltage is high, the current flowing through the primary winding is relatively low. Therefore, the cross-sectional area of the high voltage winding can be smaller compared to the low voltage winding.

Low voltage winding:
The low voltage winding, also known as the secondary winding, is designed to deliver the transformed electrical energy to the load. It is connected to the low voltage side of the transformer. The secondary winding has more turns compared to the primary winding, as it is designed to step up the low voltage to a higher voltage suitable for the load. Since the voltage is low, the current flowing through the secondary winding is relatively high. Therefore, the cross-sectional area of the low voltage winding needs to be larger compared to the high voltage winding to accommodate the higher current.

Conclusion:
In conclusion, the high voltage winding of a transformer has a smaller cross-sectional area compared to the low voltage winding. This is because the high voltage winding is designed to handle high voltages and relatively low currents, while the low voltage winding is designed to handle low voltages and relatively high currents.

High voltage winding because coil thickness is low comparing to others .......