History of electromagnetic theory used to create positively charged anodes and negatively charged cathodes. When a conductor was attached between these, the difference in the electrical potential (also known as voltage) drove a current between them through the conductor. The potential difference between two points is measured in units of volts in recognition of Volta's work. The first mention of voltaic electricity, although not recognized as such at the time, was probably made by Johann Georg Sulzer in 1767, who, upon placing a small disc of zinc under his tongue and a small disc of copper over it, observed a peculiar taste when the
Aluminium-conductor steel-reinforced cable nearby conductors the distribution of current within each conductor will be constrained to smaller regions. The resulting current crowding is termed as the proximity effect. This crowding gives an increase in the effective AC resistance of the circuit, with the effect at 60 Hertz being greater than at 50 Hertz. Geometry, conductivity, and frequency are factors in determining the amount of proximity effect. The proximity effect is result of a changing magnetic field which influences the distribution of an electric current flowing within an electrical conductor due to electromagnetic induction. When an alternating current (AC) flows through an isolated conductor,