Answer: The proximity effect is a phenomenon in which the alternating current (AC) in a conductor is redistributed due to the magnetic field of a nearby, current-carrying conductor. The interacting magnetic fields between adjacent conductors cause the current to crowd into specific areas of the conductor's cross-section.

If two conductors carry current in the same direction, the current is pushed to the outer, remote halves of the conductors. If the currents are in opposite directions, the current is concentrated on the inner, closer halves. This uneven distribution of current increases the effective resistance of the conductor, leading to greater power losses and heating.