Inductance is a property of an electrical conductor which opposes a change in current.[1] It does that by storing and releasing energy from a magnetic field surrounding the conductor when current flows, according to Faraday’s law of induction. When current rises, energy (as magnetic flux) is stored in the field, reducing the current and causing a drop in potential (i.e., a voltage) across the conductor; when current falls, energy is released from the field supplying current and causing a rise in potential across the conductor. Mutual inductance describes the change of current in a circuit when a second circuit also experiences a change of current; energy is coupled from one circuit to the other through magnetic fields.