Mutual Inductance

Mutual inductance is a measure of the ability of one current-carrying conductor to induce a current in another conductor.
For a square loop moving away from a long current-carrying conductor, the mutual inductance is given by:

where is the side length of the square loop,
is the distance between the conductor and the loop, and
is the number of turns.

As the square loop moves away from the conductor, the distance increases, resulting in a decrease in mutual inductance over time.