Electrical resistivity and conductivity 1 Ω⋅m. Electrical conductivity or specific conductance is the reciprocal of electrical resistivity, and measures a material's ability to conduct an electric current. It is commonly represented by the Greek letter σ (sigma), but κ (kappa) (especially in electrical engineering) or γ (gamma) are also occasionally used. Its SI unit is siemens per metre (S/m). In an ideal case, cross-section and physical composition of the examined material are uniform across the sample, and the electric field and current density are both parallel and constant everywhere. Many resistors and conductors do in fact have a uniform cross section with a uniform
Main Street Electrical Parade Street Electrical Parade was the Electrical Water Pageant, a show made up of fourteen 25-foot-tall (7.6 m) screens with electrical lights placed on them. Not long after the Electrical Water Pageant debuted, Card Walker commissioned the development of what became the Main Street Electrical Parade to provide Disneyland with a similar nighttime visual spectacle. The parade's design used nickel–cadmium batteries, which the Disney movie studio had recently started using, and Italian-made miniature bulbs that Disneyland staff had seen in light displays along Michigan Avenue in Chicago, Illinois. Disney arranged for the parade's original floats to be constructed by Silvestri, the