Electronics/Mutual Inductance

Mutual inductance is just like inductance except that there is a hose at the other end to collect the magnetic flow. So current through a ring generates a magnetic field which is collected by the other ring and is turned into current that moves the opposite direction. Mutual inductance relies on AC as DC does not disturb the magnetic field enough. Nominally the inductance can flow through air, but the inductance is more effective when it flows through a magnetic core such as iron.