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Thunder House
The thunder house is a scientific model invented by James Lind which gives a spectacular demonstration of the destructive effect of a lightning bolt striking a house with an imperfect lightning conductor. The small wooden house has hinged walls and carries a brass rod representing a lightning rod. A section of the conductor runs along a piece of wood placed on the façade. Inside the house is a spark gap housed in a small brass cylinder containing a small quantity of gunpowder. When the piece of wood is removed, the lightning-conductor circuit is broken. The lightning bolt, simulated by a spark generated by a Leyden jar, ignites the powder, whose explosion causes the house to collapse. If, instead, the piece of wood is positioned correctly, the electricity will be discharged to the ground, leaving the house intact. Filippo Lucci depicted a similar device in the Stanzino of the Matematiche of the Uffizi Gallery The Uffizi Gallery (; it, Galleria degli Uffizi, italic=no, ) is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Lind (naturalist)
James Lind FRS FRSE FRCPE (1736–1812) was a Scottish natural philosopher and physician. Life James Lind was born in Gorgie, Edinburgh on 17 May 1736. He studied medicine at Edinburgh University under William Cullen and Joseph Black, and graduated in 1768. In 1766, he then joined the East India Company as surgeon. In 1768 he received his doctorate (MD) from Edinburgh upon completing a dissertation on marsh fever (malaria) in Bengal. On 6 November 1770 he was admitted a Fellow of the College of Physicians, Edinburgh. Lind was also a corresponding member of the Lunar Society. Personality Lind is widely regarded as having an eccentric personality, and considered to be reckless with spending money as captured by the following dialogue: "Why, Dr. Lind, you spend a whole seas of gold", to which Lind replied, "Madam, 'tis true, my very name, behold, Begins with pounds and ends, alas, with pence" Charles Burney described Lind as extremely thin, tall, with grey hair as seen ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lightning
Lightning is a naturally occurring electrostatic discharge during which two electrically charged regions, both in the atmosphere or with one on the ground, temporarily neutralize themselves, causing the instantaneous release of an average of one gigajoule of energy. This discharge may produce a wide range of electromagnetic radiation, from heat created by the rapid movement of electrons, to brilliant flashes of visible light in the form of black-body radiation. Lightning causes thunder, a sound from the shock wave which develops as gases in the vicinity of the discharge experience a sudden increase in pressure. Lightning occurs commonly during thunderstorms as well as other types of energetic weather systems, but volcanic lightning can also occur during volcanic eruptions. The three main kinds of lightning are distinguished by where they occur: either inside a single thundercloud (intra-cloud), between two clouds (cloud-to-cloud), or between a cloud and the ground ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lightning Conductor
A lightning rod or lightning conductor (British English) is a metal rod mounted on a structure and intended to protect the structure from a lightning strike. If lightning hits the structure, it will preferentially strike the rod and be conducted to ground through a wire, instead of passing through the structure, where it could start a fire or cause electrocution. Lightning rods are also called finials, air terminals, or strike termination devices. In a lightning protection system, a lightning rod is a single component of the system. The lightning rod requires a connection to earth to perform its protective function. Lightning rods come in many different forms, including hollow, solid, pointed, rounded, flat strips, or even bristle brush-like. The main attribute common to all lightning rods is that they are all made of conductive materials, such as copper and aluminum. Copper and its alloys are the most common materials used in lightning protection. History The principle of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gunpowder
Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, carbon (in the form of charcoal) and potassium nitrate ( saltpeter). The sulfur and carbon act as fuels while the saltpeter is an oxidizer. Gunpowder has been widely used as a propellant in firearms, artillery, rocketry, and pyrotechnics, including use as a blasting agent for explosives in quarrying, mining, building pipelines and road building. Gunpowder is classified as a low explosive because of its relatively slow decomposition rate and consequently low brisance. Low explosives deflagrate (i.e., burn at subsonic speeds), whereas high explosives detonate, producing a supersonic shockwave. Ignition of gunpowder packed behind a projectile generates enough pressure to force the shot from the muzzle at high speed, but usually not enough force to rupture the gun barrel. It thus makes a good pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leyden Jar
A Leyden jar (or Leiden jar, or archaically, sometimes Kleistian jar) is an electrical component that stores a high-voltage electric charge (from an external source) between electrical conductors on the inside and outside of a glass jar. It typically consists of a glass jar with metal foil cemented to the inside and the outside surfaces, and a metal terminal projecting vertically through the jar lid to make contact with the inner foil. It was the original form of capacitor (also called a ''condenser''). Its invention was a discovery made independently by German cleric Ewald Georg von Kleist on 11 October 1745 and by Dutch scientist Pieter van Musschenbroek of Leiden (Leyden), Netherlands in 1745–1746. The Leyden jar was used to conduct many early experiments in electricity, and its discovery was of fundamental importance in the study of electrostatics. It was the first means of accumulating and preserving electric charge in large quantities that could be discharged at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filippo Lucci
Filippo is an Italian male given name, which is the equivalent of the English name Philip, from the Greek ''Philippos'', meaning "amante dei cavalli".''Behind the Name''"Given Name Philip" Retrieved on 23 January 2016. The female variant is Filippa. The name may refer to: * Filippo I Colonna (1611–1639), Italian nobleman *Filippo II Colonna (1663–1714), Italian noblemen *Filippo Abbiati (1640–1715), Italian painter *Filippo Baldinucci (1624–1697), Italian historian *Filippo Brunelleschi (1377–1446), Italian architect *Filippo Carli (1876–1938), Italian sociologist *Filippo Castagna (1765–1830), Maltese politician * Filippo Coarelli (born 1936), Italian archaeologist *Filippo Coletti (1811–1894), Italian singer * Filippo di Piero Strozzi (1541–1582), French general *Filippo Salvatore Gilii (1721–1789), Italian priest and linguist * Filippo Grandi (born 1957), Italian diplomat *Filippo Illuminato (1930-1943), Italian partisan, recipient of the Gold Medal of Mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uffizi Gallery
The Uffizi Gallery (; it, Galleria degli Uffizi, italic=no, ) is a prominent art museum located adjacent to the Piazza della Signoria in the Historic Centre of Florence in the region of Tuscany, Italy. One of the most important Italian museums and the most visited, it is also one of the largest and best known in the world and holds a collection of priceless works, particularly from the period of the Italian Renaissance. After the ruling House of Medici died out, their art collections were given to the city of Florence under the famous ''Patto di famiglia'' negotiated by Anna Maria Luisa, the last Medici heiress. The Uffizi is one of the first modern museums. The gallery had been open to visitors by request since the sixteenth century, and in 1765 it was officially opened to the public, formally becoming a museum in 1865. History The building of the Uffizi complex was begun by Giorgio Vasari in 1560 for Cosimo I de' Medici so as to accommodate the offices of the Flor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Safety
Electrical safety testing is essential to make sure electrical products and electrical installations are safe. To meet this goal, governments and various technical bodies have developed electrical safety standards. All countries have their own electrical safety standards that must be complied with. To meet to these standards, electrical products and electrical installations must pass electrical safety tests. Some types of electrical safety tests include: * dielectric withstand test (also called a hipot test) *insulation resistance test (IR test) *earth continuity test *leakage current test Electrical safety tests are described in IEC 60335, IEC 61010, AS/NZS 3000, NFPA 70, BS 7671, and other national and international standards.\ Electrical Safety tests Dielectric voltage withstand test A dielectric voltage withstand test (also known as a hipot test) is done by applying a voltage higher than operating voltage to the device or installation under test. In this test, the e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
