Royal Air Force
The Royal Air Force is the United Kingdoms aerial warfare force. Formed towards the end of the First World War on 1 April 1918, following victory over the Central Powers in 1918 the RAF emerged as, at the time, the largest air force in the world. The RAF describe its mission statement as, an agile and capable Air Force that, person for person, is second to none, and that makes a decisive air power contribution in support of the UK Defence Mission. The mission statement is supported by the RAFs definition of air power, Air power is defined as the ability to project power from the air and space to influence the behaviour of people or the course of events. Today the Royal Air Force maintains a fleet of various types of aircraft. The majority of the RAFs rotary-wing aircraft form part of the tri-service Joint Helicopter Command in support of ground forces, most of the RAFs aircraft and personnel are based in the UK, with many others serving on operations or at long-established overseas bases. It was founded on 1 April 1918, with headquarters located in the former Hotel Cecil, during the First World War, by the amalgamation of the Royal Flying Corps, at that time it was the largest air force in the world.
The RAFs naval aviation branch, the Fleet Air Arm, was founded in 1924, the RAF developed the doctrine of strategic bombing which led to the construction of long-range bombers and became its main bombing strategy in the Second World War. The RAF underwent rapid expansion prior to and during the Second World War, under the British Commonwealth Air Training Plan of December 1939, the air forces of British Commonwealth countries trained and formed Article XV squadrons for service with RAF formations. Many individual personnel from countries, and exiles from occupied Europe. By the end of the war the Royal Canadian Air Force had contributed more than 30 squadrons to serve in RAF formations, the Royal Australian Air Force represented around nine percent of all RAF personnel who served in the European and Mediterranean theatres. In the Battle of Britain in 1940, the RAF defended the skies over Britain against the numerically superior German Luftwaffe, the largest RAF effort during the war was the strategic bombing campaign against Germany by Bomber Command.
Following victory in the Second World War, the RAF underwent significant re-organisation, during the early stages of the Cold War, one of the first major operations undertaken by the Royal Air Force was in 1948 and the Berlin Airlift, codenamed Operation Plainfire. Before Britain developed its own nuclear weapons the RAF was provided with American nuclear weapons under Project E and these were initially armed with nuclear gravity bombs, being equipped with the Blue Steel missile. Following the development of the Royal Navys Polaris submarines, the nuclear deterrent passed to the navys submarines on 30 June 1969. With the introduction of Polaris, the RAFs strategic nuclear role was reduced to a tactical one and this tactical role was continued by the V bombers into the 1980s and until 1998 by Tornado GR1s. For much of the Cold War the primary role of the RAF was the defence of Western Europe against potential attack by the Soviet Union, with many squadrons based in West Germany. With the decline of the British Empire, global operations were scaled back, despite this, the RAF fought in many battles in the Cold War period
Light
Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum. The word usually refers to light, which is visible to the human eye and is responsible for the sense of sight. Visible light is defined as having wavelengths in the range of 400–700 nanometres, or 4.00 × 10−7 to 7.00 × 10−7 m. This wavelength means a range of roughly 430–750 terahertz. The main source of light on Earth is the Sun, sunlight provides the energy that green plants use to create sugars mostly in the form of starches, which release energy into the living things that digest them. This process of photosynthesis provides virtually all the used by living things. Historically, another important source of light for humans has been fire, with the development of electric lights and power systems, electric lighting has effectively replaced firelight. Some species of animals generate their own light, a process called bioluminescence, for example, fireflies use light to locate mates, and vampire squids use it to hide themselves from prey.
Visible light, as all types of electromagnetic radiation, is experimentally found to always move at this speed in a vacuum. In physics, the term sometimes refers to electromagnetic radiation of any wavelength. In this sense, gamma rays, X-rays and radio waves are light, like all types of light, visible light is emitted and absorbed in tiny packets called photons and exhibits properties of both waves and particles. This property is referred to as the wave–particle duality, the study of light, known as optics, is an important research area in modern physics. Generally, EM radiation, or EMR, is classified by wavelength into radio, infrared, the behavior of EMR depends on its wavelength. Higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths, when EMR interacts with single atoms and molecules, its behavior depends on the amount of energy per quantum it carries. There exist animals that are sensitive to various types of infrared, infrared sensing in snakes depends on a kind of natural thermal imaging, in which tiny packets of cellular water are raised in temperature by the infrared radiation. EMR in this range causes molecular vibration and heating effects, which is how these animals detect it, above the range of visible light, ultraviolet light becomes invisible to humans, mostly because it is absorbed by the cornea below 360 nanometers and the internal lens below 400.
Furthermore, the rods and cones located in the retina of the eye cannot detect the very short ultraviolet wavelengths and are in fact damaged by ultraviolet. Many animals with eyes that do not require lenses are able to detect ultraviolet, by quantum photon-absorption mechanisms, various sources define visible light as narrowly as 420 to 680 to as broadly as 380 to 800 nm
Radar
Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects. It can be used to detect aircraft, spacecraft, guided missiles, motor vehicles, weather formations, Radio waves from the transmitter reflect off the object and return to the receiver, giving information about the objects location and speed. Radar was developed secretly for military use by several nations in the period before, the term RADAR was coined in 1940 by the United States Navy as an acronym for RAdio Detection And Ranging or RAdio Direction And Ranging. The term radar has since entered English and other languages as a common noun, high tech radar systems are associated with digital signal processing, machine learning and are capable of extracting useful information from very high noise levels. Other systems similar to make use of other parts of the electromagnetic spectrum. One example is lidar, which uses ultraviolet, visible, or near infrared light from lasers rather than radio waves, as early as 1886, German physicist Heinrich Hertz showed that radio waves could be reflected from solid objects.
In 1895, Alexander Popov, an instructor at the Imperial Russian Navy school in Kronstadt. The next year, he added a spark-gap transmitter, in 1897, while testing this equipment for communicating between two ships in the Baltic Sea, he took note of an interference beat caused by the passage of a third vessel. In his report, Popov wrote that this phenomenon might be used for detecting objects, the German inventor Christian Hülsmeyer was the first to use radio waves to detect the presence of distant metallic objects. In 1904, he demonstrated the feasibility of detecting a ship in dense fog and he obtained a patent for his detection device in April 1904 and a patent for a related amendment for estimating the distance to the ship. He got a British patent on September 23,1904 for a radar system. It operated on a 50 cm wavelength and the radar signal was created via a spark-gap. In 1915, Robert Watson-Watt used radio technology to advance warning to airmen. Watson-Watt became an expert on the use of direction finding as part of his lightning experiments.
As part of ongoing experiments, he asked the new boy, Arnold Frederic Wilkins, Wilkins made an extensive study of available units before selecting a receiver model from the General Post Office. Its instruction manual noted that there was fading when aircraft flew by, in 1922, A. Hoyt Taylor and Leo C. Taylor submitted a report, suggesting that this might be used to detect the presence of ships in low visibility, eight years later, Lawrence A. Australia, New Zealand, and South Africa followed prewar Great Britain, and Hungary had similar developments during the war. Hugon, began developing a radio apparatus, a part of which was installed on the liner Normandie in 1935
Russo-Japanese War
The Russo-Japanese War was fought between the Russian Empire and the Empire of Japan over rival imperial ambitions in Manchuria and Korea. The major theatres of operations were the Liaodong Peninsula and Mukden in Southern Manchuria and the seas around Korea, Russia sought a warm-water port on the Pacific Ocean for their navy and for maritime trade. Vladivostok was operational only during the summer, whereas Port Arthur, since the end of the First Sino-Japanese War in 1895, Japan feared Russian encroachment on its sphere of influence. Russia had demonstrated an expansionist policy in the Siberian Far East from the reign of Ivan the Terrible in the 16th century, through threat of Russian expansion, Japan offered to recognize Russian dominance in Manchuria in exchange for recognition of Korea as being within the Japanese sphere of influence. Russia refused and demanded Korea north of the 39th parallel to be a buffer zone between Russia and Japan. The Japanese government perceived a Russian threat to its strategic interests, after negotiations broke down in 1904, the Japanese Navy opened hostilities by attacking the Russian Eastern Fleet at Port Arthur, China, in a surprise attack.
The war concluded with the Treaty of Portsmouth, mediated by US President Theodore Roosevelt, the complete victory of the Japanese military surprised world observers. The consequences transformed the balance of power in East Asia, resulting in a reassessment of Japans recent entry onto the world stage and it was the first major military victory in the modern era of an Asian power over a European one. Scholars continue to debate the historical significance of the war, after the Meiji Restoration in 1868, the Meiji government endeavored to assimilate Western ideas, technological advances and ways of warfare. By the late 19th century, Japan had transformed itself into an industrial state. The Japanese wanted to be recognized as equal with the Western powers, the Meiji restoration had always been intended to make Japan a modernized state, not a Westernized one, and Japan was always an imperialist power, looking towards overseas expansionism. By the 1890s it had extended its realm across Central Asia to Afghanistan, the Russian Empire stretched from Poland in the west to the Kamchatka Peninsula in the east.
With its construction of the Trans-Siberian Railway to the port of Vladivostok, in the Tsushima incident of 1861 Russia had directly assaulted Japanese territory. Between the Meiji Restoration and its participation in World War I, the first war Japan fought was the First Sino-Japanese War, fought in 1894 and 1895. The war revolved around the issue of control and influence over Korea under the rule of the Joseon dynasty, from the 1880s onward, there had been vigorous competition for influence in Korea between China and Japan. The Korean court was prone to factionalism, and was divided by a reformist faction that was pro-Japanese. In 1884, a coup attempt was put down by Chinese troops. A peasant rebellion led by the Tonghak religious movement led to a request by the Korean government for the Qing dynasty to send in troops to stabilize the country
World War I
World War I, known as the First World War, the Great War, or the War to End All Wars, was a global war originating in Europe that lasted from 28 July 1914 to 11 November 1918. More than 70 million military personnel, including 60 million Europeans, were mobilised in one of the largest wars in history and it was one of the deadliest conflicts in history, and paved the way for major political changes, including revolutions in many of the nations involved. The war drew in all the worlds great powers, assembled in two opposing alliances, the Allies versus the Central Powers of Germany and Austria-Hungary. These alliances were reorganised and expanded as more nations entered the war, Japan, the trigger for the war was the assassination of Archduke Franz Ferdinand of Austria, heir to the throne of Austria-Hungary, by Yugoslav nationalist Gavrilo Princip in Sarajevo on 28 June 1914. This set off a crisis when Austria-Hungary delivered an ultimatum to the Kingdom of Serbia. Within weeks, the powers were at war and the conflict soon spread around the world.
On 25 July Russia began mobilisation and on 28 July, the Austro-Hungarians declared war on Serbia, Germany presented an ultimatum to Russia to demobilise, and when this was refused, declared war on Russia on 1 August. Germany invaded neutral Belgium and Luxembourg before moving towards France, after the German march on Paris was halted, what became known as the Western Front settled into a battle of attrition, with a trench line that changed little until 1917. On the Eastern Front, the Russian army was successful against the Austro-Hungarians, in November 1914, the Ottoman Empire joined the Central Powers, opening fronts in the Caucasus and the Sinai. In 1915, Italy joined the Allies and Bulgaria joined the Central Powers, Romania joined the Allies in 1916, after a stunning German offensive along the Western Front in the spring of 1918, the Allies rallied and drove back the Germans in a series of successful offensives. By the end of the war or soon after, the German Empire, Russian Empire, Austro-Hungarian Empire, national borders were redrawn, with several independent nations restored or created, and Germanys colonies were parceled out among the victors.
During the Paris Peace Conference of 1919, the Big Four imposed their terms in a series of treaties, the League of Nations was formed with the aim of preventing any repetition of such a conflict. This effort failed, and economic depression, renewed nationalism, weakened successor states, and feelings of humiliation eventually contributed to World War II. From the time of its start until the approach of World War II, at the time, it was sometimes called the war to end war or the war to end all wars due to its then-unparalleled scale and devastation. In Canada, Macleans magazine in October 1914 wrote, Some wars name themselves, during the interwar period, the war was most often called the World War and the Great War in English-speaking countries. Will become the first world war in the sense of the word. These began in 1815, with the Holy Alliance between Prussia and Austria, when Germany was united in 1871, Prussia became part of the new German nation. Soon after, in October 1873, German Chancellor Otto von Bismarck negotiated the League of the Three Emperors between the monarchs of Austria-Hungary and Germany
Parabolic reflector
A parabolic reflector is a reflective surface used to collect or project energy such as light, sound, or radio waves. Its shape is part of a paraboloid, that is. The parabolic reflector transforms an incoming plane wave traveling along the axis into a spherical wave converging toward the focus, conversely, a spherical wave generated by a point source placed in the focus is reflected into a plane wave propagating as a collimated beam along the axis. Parabolic reflectors are used to collect energy from a distant source, since the principles of reflection are reversible, parabolic reflectors can be used to focus radiation from an isotropic source into a narrow beam. In optics, parabolic mirrors are used to light in reflecting telescopes and solar furnaces, and project a beam of light in flashlights, stage spotlights. In acoustics, parabolic microphones are used to record faraway sounds such as calls, in sports reporting. Strictly, the shape of the reflector is called a paraboloid. A parabola is the two-dimensional figure, however, in informal language, the word parabola and its associated adjective parabolic are often used in place of paraboloid and paraboloidal.
Correspondingly, the dimensions of a symmetrical paraboloidal dish are related by the equation,4 F D = R2, where F is the length, D is the depth of the dish. All units must be the same, if two of these three quantities are known, this equation can be used to calculate the third. A more complex calculation is needed to find the diameter of the dish measured along its surface. This is sometimes called the diameter, and equals the diameter of a flat, circular sheet of material, usually metal. Two intermediate results are useful in the calculation, P =2 F and Q = P2 + R2, where F, D, and R are defined as above. The diameter of the dish, measured along the surface, is given by, R Q P + P ln . The volume of the dish, the amount of liquid it could hold if the rim were horizontal and the vertex at the bottom, is given by 12 π R2 D, where the symbols are defined as above. This can be compared with the formulae for the volumes of a cylinder, a hemisphere (23 π R2 D, {\displaystyle \scriptstyle, and a cone. π R2 is the area of the dish, the area enclosed by the rim.
The area of the surface of the dish can be found using the area formula for a surface of revolution which gives A = π R6 D2
Wing
A wing is a type of fin that produces lift, while moving through air or some other fluid. As such, wings have a shape, a streamlined cross-sectional shape. A wings aerodynamic efficiency is expressed as its lift-to-drag ratio, the lift a wing generates at a given speed and angle of attack can be one to two orders of magnitude greater than the total drag on the wing. A high lift-to-drag ratio requires a significantly smaller thrust to propel the wings through the air at sufficient lift, lifting structures used in water, include various foils, including hydrofoils. Hydrodynamics is the science, rather than aerodynamics. Applications of underwater foils occur in hydroplanes and submarines, the word wing from the Old Norse vængr for many centuries referred mainly to the foremost limbs of birds. In nature wings have evolved in dinosaurs, mammals, reptiles, Wing forms in nature The design and analysis of the wings of aircraft is one of the principal applications of the science of aerodynamics, which is a branch of fluid mechanics.
The properties of the airflow around any moving object can - in principle - be found by solving the Navier-Stokes equations of fluid dynamics, except for simple geometries these equations are notoriously difficult to solve. Fortunately, simpler explanations can be described, for a wing to produce lift, it must be oriented at a suitable angle of attack relative to the flow of air past the wing. When this occurs the wing deflects the airflow downwards, turning the air as it passes the wing, since the wing exerts a force on the air to change its direction, the air must exert a force on the wing, equal in size but opposite in direction. This force manifests itself as differing air pressures at different points on the surface of the wing, a region of lower-than-normal air pressure is generated over the top surface of the wing, with a higher pressure on the bottom of the wing. The lower air pressure on the top of the wing generates a smaller force on the top of the wing than the upward force generated by the higher air pressure on the bottom of the wing.
Hence, a net force acts on the wing. This force is called the lift generated by the wing, the different velocities of the air passing by the wing, the air pressure differences, the change in direction of the airflow, and the lift on the wing are intrinsically one phenomenon. It is, possible to lift from any of the other three. For example, the lift can be calculated from the differences, or from different velocities of the air above and below the wing. Fluid dynamics offers other approaches to solving these problems—and all produce the same answers if done correctly, air velocity on the bottom of a wing is higher than that on the top, while the wing is generating lift. Wings with a cross section are the norm in subsonic flight
Sperry Corporation
Sperry Corporation was a major American equipment and electronics company whose existence spanned more than seven decades of the 20th century. Through a series of mergers it exists today as a part of Unisys, during World War I the company diversified into aircraft components including bomb sights and fire control systems. In their early decades, Sperry Gyroscope and related companies were concentrated on Long Island, New York, over the years, it diversified to other locations. In 1918, Lawrence Sperry split from his father to compete over aero-instruments with the Lawrence Sperry Aircraft Company, in 1924, following the death of Lawrence on December 13,1923, the two firms were brought together. The company became Sperry Corporation in 1933, the new corporation was a holding company for a number of smaller entities such as the original Sperry Gyroscope, Ford Instrument Company, Intercontinental Aviation, Inc. and others. The company made advanced aircraft navigation equipment for the market, including the Sperry Gyroscope, the company prospered during World War II as military demand skyrocketed, ranking 19th among US corporations in the value of wartime production contracts.
It specialized in high technology such as analog computer–controlled bomb sights, airborne radar systems. Postwar, the company expanded its interests in electronics and computing, producing the companys first digital computer, SPEEDAC, during the 1950s, a large part of Sperry Gyroscope moved to Phoenix and soon became the Sperry Flight Systems Company. This was to preserve parts of this company in the event of a thermonuclear conflagration. The Gyroscope division remained headquartered in New York—in its massive Lake Success, Long Island, in 1955, Sperry acquired Remington Rand and renamed itself Sperry Rand. The company remained a military contractor. From 1967 to 1973 the corporation was involved in an acrimonious antitrust lawsuit with Honeywell, the company dropped Rand from its title and reverted to Sperry Corporation. At about the time as the Rand acquisition, Sperry Gyroscope decided to open a facility that would almost exclusively produce its marine instruments. After considerable searching and evaluation, a plant was built in Charlottesville, Virginia and it was renamed Sperry Marine.
Sperry managed the operation from 1961 to 1975, of the large Louisiana Army Ammunition Plant near Minden, Sperry bought out and continued the RCA line of electronic digital computers, architectural cousins to the IBM System/360. In 1983, Sperry sold Vickers to Libbey Owens Ford, certain internal divisions of Sperry such as Sperry New Holland and Sperry Marine were sold off after the merger. This group is now part of Lockheed Martin, Sperry in Britain started with a factory in Pimlico, London in 1913, manufacturing gyroscopic compasses for the Royal Navy. It became the Sperry Gyroscope Co Ltd in 1915, in 1923, Lawrence Sperry was killed in an air crash near Rye, Sussex
Red Army
The Workers and Peasants Red Army was the army and the air force of the Russian Soviet Federative Socialist Republic, and after 1922 the Union of Soviet Socialist Republics. The army was established immediately after the 1917 October Revolution, the Bolsheviks raised an army to oppose the military confederations of their adversaries during the Russian Civil War. The Red Army is credited as being the land force in the Allied victory in the European theatre of World War II. During operations on the Eastern Front, it fought 75%–80% of the German land forces deployed in the war, inflicting the vast majority of all German losses and ultimately capturing the German capital. In September 1917, Vladimir Lenin wrote, There is only one way to prevent the restoration of the police, at the time, the Imperial Russian Army had started to collapse. The Tsarist general Nikolay Dukhonin estimated that there had been 2 million deserters,1.8 million dead,5 million wounded and 2 million prisoners and he estimated the remaining troops as numbering 10 million.
Therefore, the Council of Peoples Commissars decided to form the Red Army on 28 January 1918 and they envisioned a body formed from the class-conscious and best elements of the working classes. All citizens of the Russian republic aged 18 or older were eligible, in the event of an entire unit wanting to join the Red Army, a collective guarantee and the affirmative vote of all its members would be necessary. Because the Red Army was composed mainly of peasants, the families of those who served were guaranteed rations, some peasants who remained at home yearned to join the Army, along with some women, flooded the recruitment centres. If they were turned away they would collect scrap metal and prepare care-packages, in some cases the money they earned would go towards tanks for the Army. Nikolai Krylenko was the supreme commander-in-chief, with Aleksandr Myasnikyan as deputy, Nikolai Podvoisky became the commissar for war, Pavel Dybenko, commissar for the fleet. Proshyan, Steinberg were specified as peoples commissars as well as Vladimir Bonch-Bruyevich from the Bureau of Commissars, at a joint meeting of Bolsheviks and Left Socialist-Revolutionaries, held on 22 February 1918, Krylenko remarked, We have no army.
The Red Guard units are brushed aside like flies and we have no power to stay the enemy, only an immediate signing of the peace treaty will save us from destruction. This provoked the insurrection of General Alexey Maximovich Kaledins Volunteer Army in the River Don region, the Treaty of Brest-Litovsk aggravated Russian internal politics. The situation encouraged direct Allied intervention in the Russian Civil War, a series of engagements resulted, amongst others, the Czechoslovak Legion, the Polish 5th Rifle Division, and the pro-Bolshevik Red Latvian Riflemen. The Whites defeated the Red Army on each front, Leon Trotsky reformed and counterattacked, the Red Army repelled Admiral Kolchaks army in June, and the armies of General Denikin and General Yudenich in October. By mid-November the White armies were all almost completely exhausted, in January 1920, Budennys First Cavalry Army entered Rostov-on-Don. 1919 to 1923 At the wars start, the Red Army consisted of 299 infantry regiments, Civil war intensified after Lenin dissolved the Russian Constituent Assembly and the Soviet government signed the Treaty of Brest-Litovsk, removing Russia from the Great War
Pacific War
The Pacific War, sometimes called the Asia-Pacific War, was the theater of World War II that was fought in the Pacific and East Asia. It was fought over a vast area that included the Pacific Ocean and islands, the South West Pacific, South-East Asia, and in China. The Pacific War saw the Allied powers pitted against the Empire of Japan, the formal and official surrender of Japan took place aboard the battleship USS Missouri in Tokyo Bay on 2 September 1945. In Allied countries during the war, The Pacific War was not usually distinguished from World War II in general, or was known simply as the War against Japan. Japan used the name Greater East Asia War, as chosen by a decision on 10 December 1941. Japanese officials integrated what they called the Japan–China Incident into the Greater East Asia War, in Japan, the Fifteen Years War is used, referring to the period from the Mukden Incident of 1931 through 1945. The Phayap Army sent troops to invade and occupy northeastern Burma, involved were the Japanese puppet states of Manchukuo and Mengjiang, and the collaborationist Wang Jingwei regime.
The official policy of the U. S. Government is that Thailand was not an ally of the Axis, Japan conscripted many soldiers from its colonies of Korea and Formosa. To a small extent, some Vichy French, Indian National Army and Italy both had limited involvement in the Pacific War. The German and the Italian navies operated submarines and raiding ships in the Indian, the Italians had access to concession territory naval bases in China, while the Germans did not. After Japans attack on Pearl Harbor and the subsequent declarations of war, Free France and many other countries took part, especially forces from other British colonies. Between 1942 and 1945, there were four main areas of conflict in the Pacific War, the Central Pacific, South East Asia, U. S. sources refer to two theaters within the Pacific War, the Pacific theater and the China Burma India Theater. However these were not operational commands, in the Pacific, the Allies divided operational control of their forces between two supreme commands, known as Pacific Ocean Areas and Southwest Pacific Area.
In 1945, for a period just before the Japanese surrender. By 1937, Japan controlled Manchuria and was ready to move deeper into China, the Marco Polo Bridge Incident on 7 July 1937 provoked full-scale war between China and Japan. In August 1937, Generalissimo Chiang Kai-shek deployed his best army to fight about 300,000 Japanese troops in Shanghai, the Japanese continued to push the Chinese forces back, capturing the capital Nanking in December 1937 and committed which was known as Nanking Massacre. In March 1938, Nationalist forces won their first victory at Taierzhuang, but the city of Xuzhou was taken by Japanese in May. In June 1938, Japan deployed about 350,000 troops to invade Wuhan, the Japanese achieved major military victories, but world opinion—in particular in the United States—condemned Japan, especially after the Panay incident
Arc lamp
An arc lamp or arc light is a lamp that produces light by an electric arc. The carbon arc light, which consists of an arc between carbon electrodes in air, invented by Humphry Davy in the first decade of the 1800s, was the first practical electric light. It was widely used starting in the 1870s for street and large building lighting until it was superseded by the incandescent light in the early 20th century. It continued in use in specialized applications where a high intensity point light source was needed, such as searchlights. The carbon arc lamp is now obsolete for all of these purposes and is still made for very specialized purposes where a high intensity UV source is needed. The term is now used for gas lamps, which produce light by an arc between metal electrodes through an inert gas in a glass bulb. The common fluorescent lamp is a mercury arc lamp. The xenon arc lamp, which produces a high intensity light, is now used in many of the applications which formerly used the carbon arc, such as movie projectors.
An arc is the discharge that occurs when a gas is ionized, a high voltage is pulsed across the lamp to ignite or strike the arc, after which the discharge can be maintained at a lower voltage. The strike requires a circuit with an igniter and a ballast. The ballast is wired in series with the lamp and performs two functions, when the power is first switched on, the igniter/starter sets up a small current through the ballast and starter. This creates a magnetic field within the ballast windings. A moment the starter interrupts the current flow from the ballast, the circuit will repeat this action until the lamp is ionized enough to sustain the arc. When the lamp sustains the arc, the ballast performs its second function, the lamp and igniter are rated matched to each other, these parts must be replaced with the same rating as the failed component or the lamp will not work. The colour of the emitted by the lamp changes as its electrical characteristics change with temperature. Lightning is a principle where the atmosphere is ionized by the high potential difference between earth and storm clouds.
The temperature of the arc in an arc lamp can reach several thousand degrees Celsius, the outer glass envelope can reach 500 degrees Celsius, therefore before servicing one must ensure the bulb has cooled sufficiently to handle. Often, if these types of lamps are turned off or lose their power supply, some lamps can be restruck as soon as they are turned off.2 million candle power
Imperial Japanese Navy
The Imperial Japanese Navy was the navy of the Empire of Japan from 1868 until 1945, when it was dissolved following Japans defeat and surrender in World War II. The Japan Maritime Self-Defense Force was formed after the dissolution of the IJN, the Japanese Navy was the third largest navy in the world by 1920, behind the Royal Navy and the United States Navy. It was supported by the Imperial Japanese Navy Air Service for aircraft and it was the primary opponent of the Western Allies in the Pacific War. This eventually led to the Meiji Restoration, accompanying the re-ascendance of the Emperor came a period of frantic modernization and industrialization. Following the attempts at Mongol invasions of Japan by Kubilai Khan in 1274 and 1281, Japan undertook major naval building efforts in the 16th century, during the Warring States period, when feudal rulers vying for supremacy built vast coastal navies of several hundred ships. Around that time Japan may have developed one of the first ironclad warships when Oda Nobunaga, in 1588 Toyotomi Hideyoshi issued a ban on Wakō piracy, the pirates became vassals of Hideyoshi, and comprised the naval force used in the Japanese invasion of Korea.
Japan built her first large ocean-going warships in the beginning of the 17th century, from 1604 the Bakufu commissioned about 350 Red seal ships, usually armed and incorporating some Western technologies, mainly for Southeast Asian trade. For more than 200 years, beginning in the 1640s, the Japanese policy of seclusion forbade contacts with the outside world and prohibited the construction of ocean-going ships on pain of death. Contacts were maintained, with the Dutch through the port of Nagasaki, the Chinese through Nagasaki and the Ryukyus and Korea through intermediaries with Tsushima. Apart from Dutch trade ships no other Western vessels were allowed to enter Japanese ports, an exception was during the Napoleonic wars. However frictions with foreign ships started from the beginning of the 19th century, the Nagasaki Harbour Incident involving the HMS Phaeton in 1808 and other subsequent incidents in the following decades led to the Shogunate to enact an edict to repel foreign vessels. Western ships which were increasing their presence around Japan due to whaling, the shogunate began to strengthen the nations coastal defenses.
Numerous attempts to open Japan ended in failure in part to Japanese resistance, during 1853 and 1854, American warships under the command of Commodore Matthew Perry entered Edo Bay and made demonstrations of force requesting trade negotiations. After two hundred years of seclusion the 1854 Convention of Kanagawa led to the opening of Japan to international trade and this was soon followed by the 1858 Treaty of Amity and Commerce and treaties with other powers. In 1855, with Dutch assistance, the Shogunate acquired its first steam warship, Kankō Maru, samurai such as the future Admiral Enomoto Takeaki were sent by the Shogunate to study in the Netherlands for several years. In 1859 the Naval Training Center relocated to Tsukiji in Tokyo, in 1857 the Shogunate acquired its first screw-driven steam warship Kanrin Maru and used it as an escort for the 1860 Japanese delegation to the United States. In 1865 the French naval engineer Léonce Verny was hired to build Japans first modern naval arsenals, at Yokosuka, in 1867–1868 a British Naval mission headed by Commander Richard Tracey went to Japan to assist the development of the Japanese Navy and to organize the naval school of Tsukiji.
The Shogunate allowed and ordered various domains to purchase warships and to develop naval fleets, Satsuma, a naval center had been set up by the Satsuma domain in Kagoshima, students were sent abroad for training and a number of ships were acquired
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