Do the coils of wire in a transformer touch?

• A. Yes
• B. No
• C. Sometimes
• D. Always

Answer: (B)

In a transformer, energy is transferred by changing magnetic flux, not by direct electrical contact. The primary and secondary windings are separate coils of insulated copper that wrap around a magnetic core, but they are not electrically connected to each other. This insulation keeps the circuits electrically isolated so current in one winding can induce voltage in the other without a direct path between them. If the coils were to touch, it would create a short circuit between windings (or to the core), causing large currents, overheating, and potential damage or safety hazards. The result relies on magnetic coupling through the core, not on the windings touching.