Where are inductors commonly found?

• A. In batteries; stores chemical energy
• B. In relays, transformers, and motors; stores energy in magnetic field
• C. In light bulbs; emits light
• D. In diodes; converts AC to DC

Answer: (B)

Inductors store energy in a magnetic field and resist changes in current. This magnetic-energy role makes them essential in devices that rely on magnetic effects. In a relay, the coil’s magnetic field pulls the contacts as current flows. In a transformer, a magnetic core couples windings so energy can be transferred between circuits through changing currents. In motors, coil windings create magnetic fields that produce rotation. That’s why inductors are commonly found in relays, transformers, and motors. Batteries store chemical energy, light bulbs emit light, and diodes convert AC to DC, so those are not typical places where inductors are used.