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Shortly before his death, when he was already quite ill, von Neumann headed the United States government's top secret ICBM committee, and it would sometimes meet in his home. Its purpose was to decide on the feasibility of building an ICBM large enough to carry a thermonuclear weapon. Von Neumann had long argued that w...
Von Neumann is credited with the equilibrium strategy of mutual assured destruction, providing the deliberately humorous acronym, MAD. (Other humorous acronyms coined by von Neumann include his computer, the Mathematical Analyzer, Numerical Integrator, and Computer—or MANIAC). He also "moved heaven and earth" to bring ...
Von Neumann entered government service (Manhattan Project) primarily because he felt that, if freedom and civilization were to survive, it would have to be because the US would triumph over totalitarianism from Nazism, Fascism and Soviet Communism. During a Senate committee hearing he described his political ideology a...
Von Neumann was a founding figure in computing. Donald Knuth cites von Neumann as the inventor, in 1945, of the merge sort algorithm, in which the first and second halves of an array are each sorted recursively and then merged. Von Neumann wrote the sorting program for the EDVAC in ink, being 23 pages long; traces can ...
Von Neumann's hydrogen bomb work was played out in the realm of computing, where he and Stanislaw Ulam developed simulations on von Neumann's digital computers for the hydrodynamic computations. During this time he contributed to the development of the Monte Carlo method, which allowed solutions to complicated problems...
While consulting for the Moore School of Electrical Engineering at the University of Pennsylvania on the EDVAC project, von Neumann wrote an incomplete First Draft of a Report on the EDVAC. The paper, whose premature distribution nullified the patent claims of EDVAC designers J. Presper Eckert and John Mauchly, describ...
John von Neumann also consulted for the ENIAC project. The electronics of the new ENIAC ran at one-sixth the speed, but this in no way degraded the ENIAC's performance, since it was still entirely I/O bound. Complicated programs could be developed and debugged in days rather than the weeks required for plugboarding the...
Stochastic computing was first introduced in a pioneering paper by von Neumann in 1953. However, the theory could not be implemented until advances in computing of the 1960s. He also created the field of cellular automata without the aid of computers, constructing the first self-replicating automata with pencil and gra...
Von Neumann's team performed the world's first numerical weather forecasts on the ENIAC computer; von Neumann published the paper Numerical Integration of the Barotropic Vorticity Equation in 1950. Von Neumann's interest in weather systems and meteorological prediction led him to propose manipulating the environment by...
Von Neumann's ability to instantaneously perform complex operations in his head stunned other mathematicians. Eugene Wigner wrote that, seeing von Neumann's mind at work, "one had the impression of a perfect instrument whose gears were machined to mesh accurately to a thousandth of an inch." Paul Halmos states that "vo...
Lothar Wolfgang Nordheim described von Neumann as the "fastest mind I ever met", and Jacob Bronowski wrote "He was the cleverest man I ever knew, without exception. He was a genius." George Pólya, whose lectures at ETH Zürich von Neumann attended as a student, said "Johnny was the only student I was ever afraid of. If ...
Herman Goldstine wrote: "One of his remarkable abilities was his power of absolute recall. As far as I could tell, von Neumann was able on once reading a book or article to quote it back verbatim; moreover, he could do it years later without hesitation. He could also translate it at no diminution in speed from its orig...
"I have sometimes wondered whether a brain like von Neumann's does not indicate a species superior to that of man", said Nobel Laureate Hans Bethe of Cornell University. "It seems fair to say that if the influence of a scientist is interpreted broadly enough to include impact on fields beyond science proper, then John ...
In 1955, von Neumann was diagnosed with what was either bone or pancreatic cancer. His mother, Margaret von Neumann, was diagnosed with cancer in 1956 and died within two weeks. John had eighteen months from diagnosis till death. In this period von Neumann returned to the Roman Catholic faith that had also been signifi...
He invited a Roman Catholic priest, Father Anselm Strittmatter, O.S.B., to visit him for consultation. Von Neumann reportedly said in explanation that Pascal had a point, referring to Pascal's Wager. Father Strittmatter administered the last sacraments to him. Some of von Neumann's friends (such as Abraham Pais and Osk...
The stated clauses of the Nazi-Soviet non-aggression pact were a guarantee of non-belligerence by each party towards the other, and a written commitment that neither party would ally itself to, or aid, an enemy of the other party. In addition to stipulations of non-aggression, the treaty included a secret protocol that...
Of the territories of Poland annexed by the Soviet Union between 1939 and 1940, the region around Białystok and a minor part of Galicia east of the San river around Przemyśl were returned to the Polish state at the end of World War II. Of all other territories annexed by the USSR in 1939–40, the ones detached from Finl...
The outcome of the First World War was disastrous for both the German Reich and the Russian Soviet Federative Socialist Republic. During the war, the Bolsheviks struggled for survival, and Vladimir Lenin recognised the independence of Finland, Estonia, Latvia, Lithuania and Poland. Moreover, facing a German military ad...
At the beginning of the 1930s, the Nazi Party's rise to power increased tensions between Germany and the Soviet Union along with other countries with ethnic Slavs, who were considered "Untermenschen" (inferior) according to Nazi racial ideology. Moreover, the anti-Semitic Nazis associated ethnic Jews with both communis...
Hitler's fierce anti-Soviet rhetoric was one of the reasons why the UK and France decided that Soviet participation in the 1938 Munich Conference regarding Czechoslovakia would be both dangerous and useless. The Munich Agreement that followed marked a partial German annexation of Czechoslovakia in late 1938 followed by...
For Germany, because an autarkic economic approach or an alliance with Britain were impossible, closer relations with the Soviet Union to obtain raw materials became necessary, if not just for economic reasons alone. Moreover, an expected British blockade in the event of war would create massive shortages for Germany i...
The Soviet Union, which feared Western powers and the possibility of "capitalist encirclements", had little faith either that war could be avoided, or faith in the Polish army, and wanted nothing less than an ironclad military alliance with France and Britain that would provide a guaranteed support for a two-pronged at...
By the end of May, drafts were formally presented. In mid-June, the main Tripartite negotiations started. The discussion was focused on potential guarantees to central and east European countries should a German aggression arise. The USSR proposed to consider that a political turn towards Germany by the Baltic states w...
From April–July, Soviet and German officials made statements regarding the potential for the beginning of political negotiations, while no actual negotiations took place during that time period. The ensuing discussion of a potential political deal between Germany and the Soviet Union had to be channeled into the framew...
At the same time, British, French, and Soviet negotiators scheduled three-party talks on military matters to occur in Moscow in August 1939, aiming to define what the agreement would specify should be the reaction of the three powers to a German attack. The tripartite military talks, started in mid-August, hit a sticki...
On August 19, the 1939 German–Soviet Commercial Agreement was finally signed. On 21 August, the Soviets suspended Tripartite military talks, citing other reasons. That same day, Stalin received assurance that Germany would approve secret protocols to the proposed non-aggression pact that would place half of Poland (bor...
On 22 August, one day after the talks broke down with France and Britain, Moscow revealed that Ribbentrop would visit Stalin the next day. This happened while the Soviets were still negotiating with the British and French missions in Moscow. With the Western nations unwilling to accede to Soviet demands, Stalin instead...
Most notably, there was also a secret protocol to the pact, revealed only after Germany's defeat in 1945, although hints about its provisions were leaked much earlier, e.g., to influence Lithuania. According to said protocol Romania, Poland, Lithuania, Latvia, Estonia and Finland were divided into German and Soviet "sp...
On 24 August, Pravda and Izvestia carried news of the non-secret portions of the Pact, complete with the now infamous front-page picture of Molotov signing the treaty, with a smiling Stalin looking on. The news was met with utter shock and surprise by government leaders and media worldwide, most of whom were aware only...
Soviet propaganda and representatives went to great lengths to minimize the importance of the fact that they had opposed and fought against the Nazis in various ways for a decade prior to signing the Pact. Upon signing the pact, Molotov tried to reassure the Germans of his good intentions by commenting to journalists t...
The day after the Pact was signed, the French and British military negotiation delegation urgently requested a meeting with Soviet military negotiator Kliment Voroshilov. On August 25, Voroshilov told them "[i]n view of the changed political situation, no useful purpose can be served in continuing the conversation." Th...
On 1 September, Germany invaded Poland from the west. Within the first few days of the invasion, Germany began conducting massacres of Polish and Jewish civilians and POWs. These executions took place in over 30 towns and villages in the first month of German occupation. The Luftwaffe also took part by strafing fleeing...
On 21 September, the Soviets and Germans signed a formal agreement coordinating military movements in Poland, including the "purging" of saboteurs. A joint German–Soviet parade was held in Lvov and Brest-Litovsk, while the countries commanders met in the latter location. Stalin had decided in August that he was going t...
Eleven days after the Soviet invasion of the Polish Kresy, the secret protocol of the Molotov–Ribbentrop Pact was modified by the German–Soviet Treaty of Friendship, Cooperation and Demarcation,) allotting Germany a larger part of Poland and transferring Lithuania's territory (with the exception of left bank of river S...
After the Baltic states were forced to accept treaties, Stalin turned his sights on Finland, confident that Finnish capitulation could be attained without great effort. The Soviets demanded territories on the Karelian Isthmus, the islands of the Gulf of Finland and a military base near the Finnish capital Helsinki, whi...
In mid-June 1940, when international attention was focused on the German invasion of France, Soviet NKVD troops raided border posts in Lithuania, Estonia and Latvia. State administrations were liquidated and replaced by Soviet cadres, in which 34,250 Latvians, 75,000 Lithuanians and almost 60,000 Estonians were deporte...
Finally, on 26 June, four days after France sued for an armistice with the Third Reich, the Soviet Union issued an ultimatum demanding Bessarabia and, unexpectedly, Northern Bukovina from Romania. Two days later, the Romanians caved to the Soviet demands and the Soviets occupied the territory. The Hertza region was ini...
Elimination of Polish elites and intelligentia was part of Generalplan Ost. The Intelligenzaktion, a plan to eliminate the Polish intelligentsia, Poland's 'leadership class', took place soon after the German invasion of Poland, lasting from fall of 1939 till spring of 1940. As the result of this operation in 10 regiona...
Although Germany used forced labourers in most occupied countries, Poles and other Slavs were viewed as inferior by Nazi propaganda, thus, better suited for such duties. Between 1 and 2.5 million Polish citizens were transported to the Reich for forced labour, against their will. All Polish males were required to perfo...
On 10 January 1941, Germany and the Soviet Union signed an agreement settling several ongoing issues. Secret protocols in the new agreement modified the "Secret Additional Protocols" of the German–Soviet Boundary and Friendship Treaty, ceding the Lithuanian Strip to the Soviet Union in exchange for 7.5 million dollars ...
Before the pact's announcement, Communists in the West denied that such a treaty would be signed. Future member of the Hollywood Ten Herbert Biberman denounced rumors as "Fascist propaganda". Earl Browder, head of the Communist Party USA, stated that "there is as much chance of agreement as of Earl Browder being electe...
When anti-German demonstrations erupted in Prague, Czechoslovakia, the Comintern ordered the Czech Communist Party to employ all of its strength to paralyze "chauvinist elements." Moscow soon forced the Communist Parties of France and Great Britain to adopt an anti-war position. On 7 September, Stalin called Georgi Dim...
The Communist Party of Germany featured similar attitudes. In Die Welt, a communist newspaper published in Stockholm[e] the exiled communist leader Walter Ulbricht opposed the allies (Britain representing "the most reactionary force in the world") and argued: "The German government declared itself ready for friendly re...
When a joint German–Soviet peace initiative was rejected by Britain and France on 28 September 1939, Soviet foreign policy became critical of the Allies and more pro-German in turn. During the fifth session of the Supreme Soviet on 31 October 1939 Molotov analysed the international situation thus giving the direction f...
Molotov declared in his report entitled "On the Foreign Policy of the Soviet Union" (31 October 1939) held on the fifth (extraordinary) session of the Supreme Soviet, that the Western "ruling circles" disguise their intentions with the pretext of defending democracy against Hitlerism, declaring "their aim in war with G...
Germany and the Soviet Union entered an intricate trade pact on February 11, 1940, that was over four times larger than the one the two countries had signed in August 1939. The trade pact helped Germany to surmount a British blockade of Germany. In the first year, Germany received one million tons of cereals, half a mi...
The Soviets also helped Germany to avoid British naval blockades by providing a submarine base, Basis Nord, in the northern Soviet Union near Murmansk. This also provided a refueling and maintenance location, and a takeoff point for raids and attacks on shipping. In addition, the Soviets provided Germany with access to...
The Finnish and Baltic invasions began a deterioration of relations between the Soviets and Germany. Stalin's invasions were a severe irritant to Berlin, as the intent to accomplish these was not communicated to the Germans beforehand, and prompted concern that Stalin was seeking to form an anti-German bloc. Molotov's ...
In August 1940, the Soviet Union briefly suspended its deliveries under their commercial agreement after their relations were strained following disagreement over policy in Romania, the Soviet war with Finland, Germany falling behind in its deliveries of goods under the pact and with Stalin worried that Hitler's war wi...
After Germany entered a Tripartite Pact with Japan and Italy, Ribbentrop wrote to Stalin, inviting Molotov to Berlin for negotiations aimed to create a 'continental bloc' of Germany, Italy, Japan and the USSR that would oppose Britain and the USA. Stalin sent Molotov to Berlin to negotiate the terms for the Soviet Unio...
In an effort to demonstrate peaceful intentions toward Germany, on 13 April 1941, the Soviets signed a neutrality pact with Axis power Japan. While Stalin had little faith in Japan's commitment to neutrality, he felt that the pact was important for its political symbolism, to reinforce a public affection for Germany. S...
Nazi Germany terminated the Molotov–Ribbentrop Pact at 03:15 on 22 June 1941 by launching a massive attack on the Soviet positions in eastern Poland which marked the beginning of the invasion of the Soviet Union known as Operation Barbarossa. Stalin had ignored several warnings that Germany was likely to invade, and or...
The German original of the secret protocols was presumably destroyed in the bombing of Germany, but in late 1943, Ribbentrop had ordered that the most secret records of the German Foreign Office from 1933 on, amounting to some 9,800 pages, be microfilmed. When the various departments of the Foreign Office in Berlin wer...
The treaty was published in the United States for the first time by the St. Louis Post-Dispatch on May 22, 1946, in Britain by the Manchester Guardian. It was also part of an official State Department publication, Nazi–Soviet Relations 1939–1941, edited by Raymond J. Sontag and James S. Beddie in January 1948. The deci...
In response to the publication of the secret protocols and other secret German–Soviet relations documents in the State Department edition Nazi–Soviet Relations (1948), Stalin published Falsifiers of History, which included the claim that, during the Pact's operation, Stalin rejected Hitler's claim to share in a divisio...
For decades, it was the official policy of the Soviet Union to deny the existence of the secret protocol to the Soviet–German Pact. At the behest of Mikhail Gorbachev, Alexander Nikolaevich Yakovlev headed a commission investigating the existence of such a protocol. In December 1989, the commission concluded that the p...
Regarding the timing of German rapprochement, many historians agree that the dismissal of Maxim Litvinov, whose Jewish ethnicity was viewed unfavorably by Nazi Germany, removed an obstacle to negotiations with Germany. Stalin immediately directed Molotov to "purge the ministry of Jews." Given Litvinov's prior attempts ...
Edward Hallett Carr, a frequent defender of Soviet policy, stated: "In return for 'non-intervention' Stalin secured a breathing space of immunity from German attack."[page needed] According to Carr, the "bastion" created by means of the Pact, "was and could only be, a line of defense against potential German attack."[p...
Some critics of Stalin's policy, such as the popular writer Viktor Suvorov, claim that Stalin's primary motive for signing the Soviet–German non-aggression treaty was his calculation that such a pact could result in a conflict between the capitalist countries of Western Europe.[citation needed] This idea is supported b...
A capacitor (originally known as a condenser) is a passive two-terminal electrical component used to store electrical energy temporarily in an electric field. The forms of practical capacitors vary widely, but all contain at least two electrical conductors (plates) separated by a dielectric (i.e. an insulator that can ...
When there is a potential difference across the conductors (e.g., when a capacitor is attached across a battery), an electric field develops across the dielectric, causing positive charge +Q to collect on one plate and negative charge −Q to collect on the other plate. If a battery has been attached to a capacitor for a...
In October 1745, Ewald Georg von Kleist of Pomerania, Germany, found that charge could be stored by connecting a high-voltage electrostatic generator by a wire to a volume of water in a hand-held glass jar. Von Kleist's hand and the water acted as conductors, and the jar as a dielectric (although details of the mechani...
Daniel Gralath was the first to combine several jars in parallel into a "battery" to increase the charge storage capacity. Benjamin Franklin investigated the Leyden jar and came to the conclusion that the charge was stored on the glass, not in the water as others had assumed. He also adopted the term "battery", (denoti...
Since the beginning of the study of electricity non conductive materials like glass, porcelain, paper and mica have been used as insulators. These materials some decades later were also well-suited for further use as the dielectric for the first capacitors. Paper capacitors made by sandwiching a strip of impregnated pa...
Charles Pollak (born Karol Pollak), the inventor of the first electrolytic capacitors, found out that the oxide layer on an aluminum anode remained stable in a neutral or alkaline electrolyte, even when the power was switched off. In 1896 he filed a patent for an "Electric liquid capacitor with aluminum electrodes." So...
Last but not least the electric double-layer capacitor (now Supercapacitors) were invented. In 1957 H. Becker developed a "Low voltage electrolytic capacitor with porous carbon electrodes". He believed that the energy was stored as a charge in the carbon pores used in his capacitor as in the pores of the etched foils o...
A capacitor consists of two conductors separated by a non-conductive region. The non-conductive region is called the dielectric. In simpler terms, the dielectric is just an electrical insulator. Examples of dielectric media are glass, air, paper, vacuum, and even a semiconductor depletion region chemically identical to...
The current I(t) through any component in an electric circuit is defined as the rate of flow of a charge Q(t) passing through it, but actual charges—electrons—cannot pass through the dielectric layer of a capacitor. Rather, one electron accumulates on the negative plate for each one that leaves the positive plate, resu...
The simplest model capacitor consists of two thin parallel conductive plates separated by a dielectric with permittivity ε . This model may also be used to make qualitative predictions for other device geometries. The plates are considered to extend uniformly over an area A and a charge density ±ρ = ±Q/A exists on thei...
The maximum energy is a function of dielectric volume, permittivity, and dielectric strength. Changing the plate area and the separation between the plates while maintaining the same volume causes no change of the maximum amount of energy that the capacitor can store, so long as the distance between plates remains much...
Capacitors deviate from the ideal capacitor equation in a number of ways. Some of these, such as leakage current and parasitic effects are linear, or can be assumed to be linear, and can be dealt with by adding virtual components to the equivalent circuit of the capacitor. The usual methods of network analysis can then...
For air dielectric capacitors the breakdown field strength is of the order 2 to 5 MV/m; for mica the breakdown is 100 to 300 MV/m; for oil, 15 to 25 MV/m; it can be much less when other materials are used for the dielectric. The dielectric is used in very thin layers and so absolute breakdown voltage of capacitors is l...
Ripple current is the AC component of an applied source (often a switched-mode power supply) whose frequency may be constant or varying. Ripple current causes heat to be generated within the capacitor due to the dielectric losses caused by the changing field strength together with the current flow across the slightly r...
The capacitance of certain capacitors decreases as the component ages. In ceramic capacitors, this is caused by degradation of the dielectric. The type of dielectric, ambient operating and storage temperatures are the most significant aging factors, while the operating voltage has a smaller effect. The aging process ma...
Capacitors, especially ceramic capacitors, and older designs such as paper capacitors, can absorb sound waves resulting in a microphonic effect. Vibration moves the plates, causing the capacitance to vary, in turn inducing AC current. Some dielectrics also generate piezoelectricity. The resulting interference is especi...
In DC circuits and pulsed circuits, current and voltage reversal are affected by the damping of the system. Voltage reversal is encountered in RLC circuits that are under-damped. The current and voltage reverse direction, forming a harmonic oscillator between the inductance and capacitance. The current and voltage will...
For maximum life, capacitors usually need to be able to handle the maximum amount of reversal that a system will experience. An AC circuit will experience 100% voltage reversal, while under-damped DC circuits will experience less than 100%. Reversal creates excess electric fields in the dielectric, causes excess heatin...
Capacitors made with any type of dielectric material will show some level of "dielectric absorption" or "soakage". On discharging a capacitor and disconnecting it, after a short time it may develop a voltage due to hysteresis in the dielectric. This effect can be objectionable in applications such as precision sample a...
Leakage is equivalent to a resistor in parallel with the capacitor. Constant exposure to heat can cause dielectric breakdown and excessive leakage, a problem often seen in older vacuum tube circuits, particularly where oiled paper and foil capacitors were used. In many vacuum tube circuits, interstage coupling capacito...
Most types of capacitor include a dielectric spacer, which increases their capacitance. These dielectrics are most often insulators. However, low capacitance devices are available with a vacuum between their plates, which allows extremely high voltage operation and low losses. Variable capacitors with their plates open...
Several solid dielectrics are available, including paper, plastic, glass, mica and ceramic materials. Paper was used extensively in older devices and offers relatively high voltage performance. However, it is susceptible to water absorption, and has been largely replaced by plastic film capacitors. Plastics offer bette...
Electrolytic capacitors use an aluminum or tantalum plate with an oxide dielectric layer. The second electrode is a liquid electrolyte, connected to the circuit by another foil plate. Electrolytic capacitors offer very high capacitance but suffer from poor tolerances, high instability, gradual loss of capacitance espec...
Several other types of capacitor are available for specialist applications. Supercapacitors store large amounts of energy. Supercapacitors made from carbon aerogel, carbon nanotubes, or highly porous electrode materials, offer extremely high capacitance (up to 5 kF as of 2010[update]) and can be used in some applicatio...
If a capacitor is driven with a time-varying voltage that changes rapidly enough, at some frequency the polarization of the dielectric cannot follow the voltage. As an example of the origin of this mechanism, the internal microscopic dipoles contributing to the dielectric constant cannot move instantly, and so as frequ...
where a single prime denotes the real part and a double prime the imaginary part, Z(ω) is the complex impedance with the dielectric present, Ccmplx(ω) is the so-called complex capacitance with the dielectric present, and C0 is the capacitance without the dielectric. (Measurement "without the dielectric" in principle me...
The arrangement of plates and dielectric has many variations depending on the desired ratings of the capacitor. For small values of capacitance (microfarads and less), ceramic disks use metallic coatings, with wire leads bonded to the coating. Larger values can be made by multiple stacks of plates and disks. Larger val...
Capacitors may have their connecting leads arranged in many configurations, for example axially or radially. "Axial" means that the leads are on a common axis, typically the axis of the capacitor's cylindrical body – the leads extend from opposite ends. Radial leads might more accurately be referred to as tandem; they ...
Small, cheap discoidal ceramic capacitors have existed since the 1930s, and remain in widespread use. Since the 1980s, surface mount packages for capacitors have been widely used. These packages are extremely small and lack connecting leads, allowing them to be soldered directly onto the surface of printed circuit boar...
Mechanically controlled variable capacitors allow the plate spacing to be adjusted, for example by rotating or sliding a set of movable plates into alignment with a set of stationary plates. Low cost variable capacitors squeeze together alternating layers of aluminum and plastic with a screw. Electrical control of capa...
Most capacitors have numbers printed on their bodies to indicate their electrical characteristics. Larger capacitors like electrolytics usually display the actual capacitance together with the unit (for example, 220 μF). Smaller capacitors like ceramics, however, use a shorthand consisting of three numeric digits and a...
Capacitors are connected in parallel with the power circuits of most electronic devices and larger systems (such as factories) to shunt away and conceal current fluctuations from the primary power source to provide a "clean" power supply for signal or control circuits. Audio equipment, for example, uses several capacit...
In electric power distribution, capacitors are used for power factor correction. Such capacitors often come as three capacitors connected as a three phase load. Usually, the values of these capacitors are given not in farads but rather as a reactive power in volt-amperes reactive (var). The purpose is to counteract ind...
When an inductive circuit is opened, the current through the inductance collapses quickly, creating a large voltage across the open circuit of the switch or relay. If the inductance is large enough, the energy will generate a spark, causing the contact points to oxidize, deteriorate, or sometimes weld together, or dest...
In single phase squirrel cage motors, the primary winding within the motor housing is not capable of starting a rotational motion on the rotor, but is capable of sustaining one. To start the motor, a secondary "start" winding has a series non-polarized starting capacitor to introduce a lead in the sinusoidal current. W...
Capacitors may retain a charge long after power is removed from a circuit; this charge can cause dangerous or even potentially fatal shocks or damage connected equipment. For example, even a seemingly innocuous device such as a disposable-camera flash unit, powered by a 1.5 volt AA battery, has a capacitor which may co...
Capacitors may catastrophically fail when subjected to voltages or currents beyond their rating, or as they reach their normal end of life. Dielectric or metal interconnection failures may create arcing that vaporizes the dielectric fluid, resulting in case bulging, rupture, or even an explosion. Capacitors used in RF ...
The history of science is the study of the development of science and scientific knowledge, including both the natural sciences and social sciences. (The history of the arts and humanities is termed as the history of scholarship.) Science is a body of empirical, theoretical, and practical knowledge about the natural wo...
The English word scientist is relatively recent—first coined by William Whewell in the 19th century. Previously, people investigating nature called themselves natural philosophers. While empirical investigations of the natural world have been described since classical antiquity (for example, by Thales, Aristotle, and o...
From the 18th century through late 20th century, the history of science, especially of the physical and biological sciences, was often presented in a progressive narrative in which true theories replaced false beliefs. More recent historical interpretations, such as those of Thomas Kuhn, tend to portray the history of ...
The development of writing enabled knowledge to be stored and communicated across generations with much greater fidelity. Combined with the development of agriculture, which allowed for a surplus of food, it became possible for early civilizations to develop, because more time and effort could be devoted to tasks (othe...