Assuming the left side of the transformer is the primary side, what type of transformer would show fewer turns on the secondary side?

In a transformer setup, the relationship between the number of turns in the primary and secondary windings determines whether it is a step-up or step-down transformer. A step-down transformer is specifically designed to reduce voltage by having fewer turns of wire on the secondary side compared to the primary side. This reduction in turns allows for a lower output voltage than the input voltage.

The principle behind this operation is based on Faraday's law of electromagnetic induction, where the voltage induced in the secondary winding is proportional to the ratio of the number of turns between the two sides. When the secondary winding has fewer turns, it results in a lower voltage output, characteristic of step-down transformers.

In contrast, a step-up transformer has more turns in the secondary than in the primary, producing a higher output voltage. An isolation transformer is used primarily for safety and does not necessarily alter voltage levels, and an autotransformer also modifies voltage levels but operates differently by using a single winding for both primary and secondary functions.

Thus, the correct understanding of why a step-down transformer has fewer turns on the secondary side is crucial for grasping the fundamental operation of transformers and their applications in electrical engineering.