What term relates to the phenomenon where current is conducted near the surface of an alternating current conductor?

The phenomenon where current is conducted near the surface of an alternating current conductor is known as the skin effect. This effect occurs due to the alternating nature of the current, which induces opposing magnetic fields that push the current density toward the conductor's surface. As the frequency of the alternating current increases, the depth to which the current penetrates the conductor decreases, causing a greater concentration of current near the surface.

Understanding the skin effect is essential for linemen as it impacts the design and selection of conductors for high-frequency applications, such as in power transmission and high-voltage systems. This effect leads to increased resistance and losses in AC systems, so it is vital to account for it when evaluating conductor performance.

The other terms listed relate to different electrical concepts: impedance encompasses both resistance and reactance in an AC circuit, capacitance refers to the ability of a component to store electrical energy in an electric field, and leakage current describes unintended current that bypasses the intended circuit paths. Each of these concepts plays a role in electrical systems but does not specifically reference the surface conduction of current in AC conductors like the skin effect does.