Which phenomenon occurs when a highly charged pointed conductor attracts air molecules through charge separation?

The phenomenon that occurs when a highly charged pointed conductor attracts air molecules through charge separation is known as corona discharge. This process is associated with the creation of a localized electric field around the sharp point of the conductor, which is significant because the curvature of the point enhances the electric field strength. When the field becomes strong enough, it ionizes the surrounding air molecules, allowing them to become charged and move towards the conductor.

As air molecules are attracted, they accumulate around the conductor, resulting in a visible glow often observed in high voltage equipment. This is also the basis for various applications, such as in spark plugs and certain types of electrical discharge systems. The other phenomena listed do not directly describe this process; Coulomb's law relates to the force between charged objects, electric potential refers to the potential energy per unit charge, and the photovoltaic effect involves the generation of electricity from light without the characteristic ionization seen in corona discharge.