Search results
Results from the WOW.Com Content Network
The first electroscope was a pivoted needle (called the versorium), invented by British physician William Gilbert around 1600. [1] [2] The pith-ball electroscope and the gold-leaf electroscope are two classical types of electroscope [2] that are still used in physics education to demonstrate the principles of electrostatics.
Headline from the New York Times article on Szczepanik's telectroscope (April 3, 1898). Nevertheless, the word "telectroscope" was widely accepted. It was used to describe the work of nineteenth century inventors and scientists such as Constantin Senlecq, [6] George R. Carey, [7] Adriano de Paiva, and later Jan Szczepanik, who with Ludwig Kleiberg obtained a British patent (patent nr. 5031) [8 ...
A gold-leaf electroscope (E), a sensitive detector of electric charge, is attached by a wire to the outside of the pail. When the charged ball is lowered into the pail without touching it, the electroscope registers a charge, indicating that the ball induces charge in the metal container by electrostatic induction. An opposite charge is induced ...
Gold leaf electroscope demonstrating the photoelectric effect. When the electroscope disk is negatively charged with excess electrons, the gold leaves mutually repel. If high-energy light (such as ultraviolet) is then shone on the disk, electrons are emitted by the photoelectric effect and the leaf repulsion ceases.
Critical temperature T c, the temperature below which the wire becomes a superconductor; Critical current density J c, the maximum current a superconducting wire can carry per unit cross-sectional area (see images below for examples with 20 kA/cm 2). Superconducting wires/tapes/cables usually consist of two key features:
The first rubber-insulated cables for US building wiring were introduced in 1922 with US patent 1458803, Burley, Harry & Rooney, Henry, "Insulated electric wire", issued 1923-06-12, assigned to Boston Insulated Wire and Cable . These were two or more solid copper electrical wires with rubber insulation, plus woven cotton cloth over each ...
A single-wire transmission line (or single wire method) is a method of transmitting electrical power or signals using only a single electrical conductor. This is in contrast to the usual use of a pair of wires providing a complete circuit, or an electrical cable likewise containing (at least) two conductors for that purpose.
Synonyms for this device include galvanoscopic frog, frog's leg galvanoscope, frog galvanometer, rheoscopic frog, and frog electroscope. The device is properly called a galvanoscope rather than galvanometer since the latter implies accurate measurement whereas a galvanoscope only gives an indication. [ 2 ]