Mutual Inductance & Self-Inductance Explained | Transformer Basics When current flows through one coil, it creates a magnetic field that induces a voltage in a nearby coil—this is mutual inductance, the working principle of transformers. On the other hand, when current changes in a single coil, it induces an opposing voltage within itself—this is self-inductance, which slows down current changes in circuits. Understanding these concepts is crucial for electrical engineers, students, and anyone i