Which action strengthens a coil inductor?

• A. Limiting and separating the coils
• B. Adding coils close together
• C. Adding and separating the coils
• D. None of the above

Answer: (B)

Strengthening an inductor comes from increasing how much magnetic flux links all of the windings. When you add more turns and place them close together on the same core, the magnetic field produced by each turn links more of the other turns. This boosts the total inductance because L grows with the amount of flux linkage, and the coupling between windings is stronger when they’re tightly wound together. Keeping coils apart reduces that linkage, lowering inductance, and simply adding and separating doesn’t maximize the magnetic coupling. So, adding coils close together is the way to increase the inductance.