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Stephen Butterworth
Stephen Butterworth (1885–1958) was a British physicist who invented the filter that bears his name, a class of electrical circuits that separates electrical signals of different frequencies. Biography Stephen Butterworth was born on 11 August 1885 in Rochdale, Lancashire, England (a town located about 10 miles north of the city of Manchester). He was the son of Alexander Butterworth, a postman, and Elizabeth (maiden name Wynn). He was the second of four children. In 1904, he entered the Victoria University of Manchester, from which he received, in 1907, both a Bachelor of Science degree in physics (first class) and a teacher's certificate (first class). In 1908 he received a Master of Science degree in physics. For the next 11 years he was a physics lecturer at the Manchester Municipal College of Technology. He subsequently worked for several years at the National Physical Laboratory, where he did theoretical and experimental work for the determination of standards of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rochdale
Rochdale ( ) is a town in Greater Manchester, England, and the administrative centre of the Metropolitan Borough of Rochdale. In the United Kingdom 2021 Census, 2021 Census, the town had a population of 111,261, compared to 223,773 for the wider borough. Rochdale is in the foothills of the South Pennines and lies in the Dale (landform), dale (valley) of the River Roch, north-west of Oldham and north-east of Manchester. Rochdale's recorded history begins with an entry in the Domesday Book of 1086 as ''Recedham Manor'', but can be traced back to the 9th century. The Rochdale (ancient parish), ancient parish of Rochdale was a division of the Salford Hundred and one of the larger ecclesiastical parishes in England, comprising several Township (England), townships. By 1251, the town had become of such importance that it was granted a royal charter. The town became a centre of northern England's woollen trade and, by the early 18th century, was described as being "remarkable for i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alternating Current
Alternating current (AC) is an electric current that periodically reverses direction and changes its magnitude continuously with time, in contrast to direct current (DC), which flows only in one direction. Alternating current is the form in which electric power is delivered to businesses and residences, and it is the form of electrical energy that consumers typically use when they plug kitchen appliances, televisions, Fan (machine), fans and electric lamps into a wall socket. The abbreviations ''AC'' and ''DC'' are often used to mean simply ''alternating'' and ''direct'', respectively, as when they modify ''Electric current, current'' or ''voltage''. The usual waveform of alternating current in most electric power circuits is a sine wave, whose positive half-period corresponds with positive direction of the current and vice versa (the full period is called a ''wave cycle, cycle''). "Alternating current" most commonly refers to power distribution, but a wide range of other appl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1885 Births
Events January * January 3– 4 – Sino-French War – Battle of Núi Bop: French troops under General Oscar de Négrier defeat a numerically superior Qing Chinese force, in northern Vietnam. * January 17 – Mahdist War in Sudan – Battle of Abu Klea: British troops defeat Mahdist forces. * January 20 – American inventor LaMarcus Adna Thompson patents a roller coaster. * January 24 – Irish rebels damage Westminster Hall and the Tower of London with dynamite. * January 26 – Mahdist War in Sudan: Troops loyal to Mahdi Muhammad Ahmad conquer Khartoum; British commander Charles George Gordon is killed. February * February 5 – King Leopold II of Belgium establishes the Congo Free State, as a personal possession. * February 9 – The first Japanese arrive in Hawaii. * February 16 – Charles Dow publishes the first edition of the Dow Jones Industrial Average. The index stands at a level of 62.76, and r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
People From Rochdale
The term "the people" refers to the public or common mass of people of a polity. As such it is a concept of human rights law, international law as well as constitutional law, particularly used for claims of popular sovereignty. In contrast, a people is any plurality of persons considered as a whole. Used in politics and law, the term "a people" refers to the collective or community of an ethnic group or nation. Concepts Legal Chapter One, Article One of the Charter of the United Nations states that "peoples" have the right to self-determination. Though the mere status as peoples and the right to self-determination, as for example in the case of Indigenous peoples (''peoples'', as in all groups of indigenous people, not merely all indigenous persons as in ''indigenous people''), does not automatically provide for independent sovereignty and therefore secession. Indeed, judge Ivor Jennings identified the inherent problems in the right of "peoples" to self-determination, as i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
English Physicists
English usually refers to: * English language * English people English may also refer to: Culture, language and peoples * ''English'', an adjective for something of, from, or related to England * ''English'', an Amish term for non-Amish, regardless of ethnicity * English studies, the study of English language and literature Media * ''English'' (2013 film), a Malayalam-language film * ''English'' (novel), a Chinese book by Wang Gang ** ''English'' (2018 film), a Chinese adaptation * ''The English'' (TV series), a 2022 Western-genre miniseries * ''English'' (play), a 2022 play by Sanaz Toossi People and fictional characters * English (surname), a list of people and fictional characters * English Fisher (1928–2011), American boxing coach * English Gardner (born 1992), American track and field sprinter * English McConnell (1882–1928), Irish footballer * Aiden English, a ring name of Matthew Rehwoldt (born 1987), American former professional wrestl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anderson's Bridge
In electronics, Anderson's bridge is a bridge circuit used to measure the self-inductance of the coil. It enables measurement of inductance by utilizing other circuit components like resistors and capacitors. Anderson's bridge was invented by Alexander Anderson in 1891. He modified Maxwell's inductance capacitance bridge so that it gives very accurate measurement of self-inductance. Balance conditions The balance conditions for Anderson's bridge or, equivalently the values of the self-inductance and resistance of the given coil can be found using basic circuit analysis techniques such as KCL, KVL and using phasors. Consider the circuit diagram of Anderson's bridge in the given figure. Let L1 be the self-inductance and R1 be the electrical resistance of the coil under consideration. Since the voltmeter is ideally assumed to have nearly infinite impedance, the currents in branches ab and bc and those in the branches de and ec are taken to be equal. Applying Kirchhoff's current l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Degaussing
Degaussing, or deperming, is the process of decreasing or eliminating a remnant magnetic field. It is named after the gauss, a unit of magnetism, which in turn was named after Carl Friedrich Gauss. Due to magnetic hysteresis, it is generally not possible to reduce a magnetic field completely to zero, so degaussing typically induces a very small "known" field referred to as bias. Degaussing was originally applied to reduce ships' magnetic signatures during World War II. Degaussing is also used to reduce magnetic fields in tape recorders and cathode-ray tube displays, and to destroy data held on magnetic storage. Ships' hulls The term was first used by then-Commander Charles F. Goodeve, Royal Canadian Naval Volunteer Reserve, during World War II while trying to counter the German magnetic naval mines that were wreaking havoc on the British fleet. The mines detected the increase in the magnetic field when the steel in a ship concentrated the Earth's magnetic field over it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naval Mine
A naval mine is a self-contained explosive weapon placed in water to damage or destroy surface ships or submarines. Similar to anti-personnel mine, anti-personnel and other land mines, and unlike purpose launched naval depth charges, they are deposited and left to wait until, depending on their fuzing, they are triggered by the approach of or contact with any vessel. Naval mines can be used offensively, to hamper enemy shipping movements or lock vessels into a harbour; or defensively, to create "safe" zones protecting friendly sea lanes, harbours, and naval assets. Mines allow the minelaying force commander to concentrate warships or defensive assets in mine-free areas giving the adversary three choices: undertake a resource-intensive and time-consuming minesweeping effort, accept the casualties of challenging the minefield, or use the unmined waters where the greatest concentration of enemy firepower will be encountered. Although international law requires signatory nations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such a device was called an automotive, automobile, locomotive, or fish torpedo; colloquially, a ''fish''. The term ''torpedo'' originally applied to a variety of devices, most of which would today be called mines. From about 1900, ''torpedo'' has been used strictly to designate a self-propelled underwater explosive device. While the 19th-century battleship had evolved primarily with a view to engagements between armored warships with large-caliber guns, the invention and refinement of torpedoes from the 1860s onwards allowed small torpedo boats and other lighter surface vessels, submarines/submersibles, even improvised fishing boats or frogmen, and later light aircraft, to destroy large ships without the need of large guns, though somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Underwater Explosion
An underwater explosion (also known as an UNDEX) is a explosive material, chemical or nuclear explosive, nuclear explosion that occurs under the surface of a body of water. While useful in anti-ship and submarine warfare, underwater bombs are not as effective against coastal facilities. Properties of water Underwater explosions differ from in-air explosions due to the properties of water: *Mass and compressibility, incompressibility (all explosions) – water has a much higher density than air, which makes water harder to move (higher inertia). It is also relatively hard to compress (increase density) when under pressure in a low range (up to about 100 atmospheres). These two together make water an excellent conductor of shock waves from an explosion. *Effect of neutron exposure on salt water (nuclear explosions only) – most underwater blast scenarios happen in seawater, not fresh or pure water. The water itself is not much affected by neutrons but salt is strongly affected. Whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Admiralty Research Laboratory
The Admiralty Research Laboratory (ARL) was a research laboratory that supported the work of the UK Admiralty. It was located in Teddington, London, England from 1921 to 1977. History During the First World War, the Anti-Submarine Division of the Admiralty had established experimental stations at Hawkcraig (Aberdour) and Parkeston Quay, Harwich, with out-stations at Dartmouth and Wemyss Bay, to work on submarine detection methods. The Admiralty also established an experimental station at Shandon, Dumbartonshire, working with the Lancashire Anti-Submarine Committee and the Clyde Anti-Submarine Committee, which subsequently moved to Teddington in 1921, becoming the Admiralty Research Laboratory. Its main fields of research expanded to include oceanography (it housed the National Institute of Oceanography from 1949 to 1953); electromagnetics and degaussing; underwater ballistics; visual aids; acoustics; infra-red radiation; photography and assessment techniques. It moved ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
