Which of the following is not a component of a transformer?

• A. Core
• B. Windings
• C. Plate
• D. Insulation

Answer: (C)

A transformer works because of three essential parts: a magnetic core to provide a low-reluctance path for flux, windings that carry the electrical energy on the primary and secondary sides, and insulation to keep those windings safely separated and dielectrically protected. The core guides the magnetic flux between windings, enabling energy transfer without direct electrical contact. The windings are the actual conductive pathways where voltage and current are induced. Insulation ensures there’s no shorting between windings or to the core and helps with thermal and electrical safety.

A plate isn’t a separate functional element in this energy-transfer system. The core itself is made from laminated sheets (often called laminations or plates) that form the magnetic path, but these plates are part of the core assembly rather than an independent component you would list alongside core, windings, and insulation. Therefore, plate doesn’t qualify as a distinct transformer component.