In von Neumann's model what does p represent?

along with two inequality systems expressing economic efficiency. In this model, the (transposed) probability vector p represents the prices of the goods while the probability vector q represents the "intensity" at which the production process would run. The unique solution λ represents the growth factor which is 1 plus the rate of growth of the economy; the rate of growth equals the interest rate. Proving the existence of a positive growth rate and proving that the growth rate equals the interest rate were remarkable achievements, even for von Neumann.


In von Neumann's model what does q represent?


What were von Neumann's model an example of?

Von Neumann's results have been viewed as a special case of linear programming, where von Neumann's model uses only nonnegative matrices. The study of von Neumann's model of an expanding economy continues to interest mathematical economists with interests in computational economics. This paper has been called the greatest paper in mathematical economics by several authors, who recognized its introduction of fixed-point theorems, linear inequalities, complementary slackness, and saddlepoint duality. In the proceedings of a conference on von Neumann's growth model, Paul Samuelson said that many mathematicians had developed methods useful to economists, but that von Neumann was unique in having made significant contributions to economic theory itself.


What was the significance of von Neumann's model of expanding economy?


What ideas were utilized in von Neumann's ecocomic model?


When did von Neumann's interest in economics begin?

Von Neumann's famous 9-page paper started life as a talk at Princeton and then became a paper in Germany, which was eventually translated into English. His interest in economics that led to that paper began as follows: When lecturing at Berlin in 1928 and 1929 he spent his summers back home in Budapest, and so did the economist Nicholas Kaldor, and they hit it off. Kaldor recommended that von Neumann read a book by the mathematical economist Léon Walras. Von Neumann found some faults in that book and corrected them, for example, replacing equations by inequalities. He noticed that Walras's General Equilibrium Theory and Walras' Law, which led to systems of simultaneous linear equations, could produce the absurd result that the profit could be maximized by producing and selling a negative quantity of a product. He replaced the equations by inequalities, introduced dynamic equilibria, among other things, and eventually produced the paper.


What economist did von Neumann get to know that spurred the interest in economics?


In who's book did von Neuman find errors in the author's equations?


What was the new method of linear programming that von Neumann suggested?

Later, von Neumann suggested a new method of linear programming, using the homogeneous linear system of Gordan (1873), which was later popularized by Karmarkar's algorithm. Von Neumann's method used a pivoting algorithm between simplices, with the pivoting decision determined by a nonnegative least squares subproblem with a convexity constraint (projecting the zero-vector onto the convex hull of the active simplex). Von Neumann's algorithm was the first interior point method of linear programming.


What was von Neumann's method known to be the first of?


When did von NEumann establish mean square ratio?

Von Neumann made fundamental contributions to mathematical statistics. In 1941, he derived the exact distribution of the ratio of the mean square of successive differences to the sample variance for independent and identically normally distributed variables. This ratio was applied to the residuals from regression models and is commonly known as the Durbin–Watson statistic for testing the null hypothesis that the errors are serially independent against the alternative that they follow a stationary first order autoregression.


The algorithm defining artificial viscosity is a fundamental contribution to what area?

Von Neumann made fundamental contributions in exploration of problems in numerical hydrodynamics. For example, with Robert D. Richtmyer he developed an algorithm defining artificial viscosity that improved the understanding of shock waves. A problem was that when computers solved hydrodynamic or aerodynamic problems, they tried to put too many computational grid points at regions of sharp discontinuity (shock waves). The mathematics of artificial viscosity smoothed the shock transition without sacrificing basic physics. Other well known contributions to fluid dynamics included the classic flow solution to blast waves, and the co-discovery of the ZND detonation model of explosives.


What did the math of artificial viscosity do?


What was the problem of computers solving fluid dynamics?


What principal contribution did von Neumann make to atomic bomb?

Von Neumann's principal contribution to the atomic bomb was in the concept and design of the explosive lenses needed to compress the plutonium core of the Fat Man weapon that was later dropped on Nagasaki. While von Neumann did not originate the "implosion" concept, he was one of its most persistent proponents, encouraging its continued development against the instincts of many of his colleagues, who felt such a design to be unworkable. He also eventually came up with the idea of using more powerful shaped charges and less fissionable material to greatly increase the speed of "assembly".


Did von Nemann think that the atomic bomb design was not workable?


What additional ideas did von Neumann contribute to Atomic bomb?


what change was made when shortage of uranium 235 was apparent?

When it turned out that there would not be enough uranium-235 to make more than one bomb, the implosive lens project was greatly expanded and von Neumann's idea was implemented. Implosion was the only method that could be used with the plutonium-239 that was available from the Hanford Site. He established the design of the explosive lenses required, but there remained concerns about "edge effects" and imperfections in the explosives. His calculations showed that implosion would work if it did not depart by more than 5% from spherical symmetry. After a series of failed attempts with models, this was achieved by George Kistiakowsky, and the construction of the Trinity bomb was completed in July 1945.


What was the tolerance limit for implosion "edge effect"?


In what year was Trinity bomb completed?


What other people worked with von Neumann on target selection?

Along with four other scientists and various military personnel, von Neumann was included in the target selection committee responsible for choosing the Japanese cities of Hiroshima and Nagasaki as the first targets of the atomic bomb. Von Neumann oversaw computations related to the expected size of the bomb blasts, estimated death tolls, and the distance above the ground at which the bombs should be detonated for optimum shock wave propagation and thus maximum effect. The cultural capital Kyoto, which had been spared the bombing inflicted upon militarily significant cities, was von Neumann's first choice, a selection seconded by Manhattan Project leader General Leslie Groves. However, this target was dismissed by Secretary of War Henry L. Stimson.


What role did von Neuman play in the selection of targets?


What was von Neumann's first choice for target city?


Who dismissed von Neuamann's primary target city?


On July 16, 1945, with numerous other Manhattan Project personnel, von Neumann was an eyewitness to the first atomic bomb blast, code named Trinity, conducted as a test of the implosion method device, at the bombing range near Alamogordo Army Airfield, 35 miles (56 km) southeast of Socorro, New Mexico. Based on his observation alone, von Neumann estimated the test had resulted in a blast equivalent to 5 kilotons of TNT (21 TJ) but Enrico Fermi produced a more accurate estimate of 10 kilotons by dropping scraps of torn-up paper as the shock wave passed his location and watching how far they scattered. The actual power of the explosion had been between 20 and 22 kilotons. It was in von Neumann's 1944 papers that the expression "kilotons" appeared for the first time. After the war, Robert Oppenheimer remarked that the physicists involved in the Manhattan project had "known sin". Von Neumann's response was that "sometimes someone confesses a sin in order to take credit for it."


Where did the first atomic blast test take place?


What was the power of the first atomic blast?


With whom did von Neumann collaborate for further development of the hydrogen bomb?

Von Neumann continued unperturbed in his work and became, along with Edward Teller, one of those who sustained the hydrogen bomb project. He then collaborated with Klaus Fuchs on further development of the bomb, and in 1946 the two filed a secret patent on "Improvement in Methods and Means for Utilizing Nuclear Energy", which outlined a scheme for using a fission bomb to compress fusion fuel to initiate nuclear fusion. The Fuchs–von Neumann patent used radiation implosion, but not in the same way as is used in what became the final hydrogen bomb design, the Teller–Ulam design. Their work was, however, incorporated into the "George" shot of Operation Greenhouse, which was instructive in testing out concepts that went into the final design. The Fuchs–von Neumann work was passed on, by Fuchs, to the Soviet Union as part of his nuclear espionage, but it was not used in the Soviets' own, independent development of the Teller–Ulam design. The historian Jeremy Bernstein has pointed out that ironically, "John von Neumann and Klaus Fuchs, produced a brilliant invention in 1946 that could have changed the whole course of the development of the hydrogen bomb, but was not fully understood until after the bomb had been successfully made."


What improvement did von Neumann see in the nuclear weaponry?


What country was afforded access to design of improved nuclear weapon through espionage?


In 1950 von Neumann became a consultant for what organization?

In 1950, von Neumann became a consultant to the Weapons Systems Evaluation Group (WSEG), whose function was to advise the Joint Chiefs of Staff and the United States Secretary of Defense on the development and use of new technologies. He also became an adviser to the Armed Forces Special Weapons Project (AFSWP), which was responsible for the military aspects on nuclear weapons.Over the following two years, he also became a consultant to the Central Intelligence Agency (CIA), a member of the influential General Advisory Committee of the Atomic Energy Commission, a consultant to the newly established Lawrence Livermore National Laboratory, and a member of the Scientific Advisory Group of the United States Air Force.


What military organization did von NEumann also consult with for military aspect of nuclear weapons?


What committee did von Neumann serve on within the Atomic Energy Commission?


In what year did von Neumann become commissioner of the AEC?

In 1955, von Neumann became a commissioner of the AEC. He accepted this position and used it to further the production of compact hydrogen bombs suitable for Intercontinental ballistic missile delivery. He involved himself in correcting the severe shortage of tritium and lithium 6 needed for these compact weapons, and he argued against settling for the intermediate range missiles that the Army wanted. He was adamant that H-bombs delivered into the heart of enemy territory by an ICBM would be the most effective weapon possible, and that the relative inaccuracy of the missile wouldn't be a problem with an H-bomb. He said the Russians would probably be building a similar weapon system, which turned out to be the case. Despite his disagreement with Oppenheimer over the need for a crash program to develop the hydrogen bomb, he testified on the latter's behalf at the 1954 Oppenheimer security hearing, at which he asserted that Oppenheimer was loyal, and praised him for his helpfulness once the program went ahead.


What were compact hydrogen bombs useful for?


What was the concern with longer range ICBM with Hbomb?


Von Neumann testified at whose hearing about loyalty and help?


What was the purpose of top secret ICBM committee?

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 while the technical obstacles were sizable, they could be overcome in time. The SM-65 Atlas passed its first fully functional test in 1959, two years after his death. The feasibility of an ICBM owed as much to improved, smaller warheads as it did to developments in rocketry, and his understanding of the former made his advice invaluable.


What argument did von Neumann make about ICBMs?


In what year did SM-65 Atlas pass its first fully functional test?


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 MAD about. His goal was to quickly develop ICBMs and the compact hydrogen bombs that they could deliver to the USSR, and he knew the Soviets were doing similar work because the CIA interviewed German rocket scientists who were allowed to return to Germany, and von Neumann had planted a dozen technical people in the CIA. The Russians believed that bombers would soon be vulnerable, and they shared von Neumann's view that an H-bomb in an ICBM was the ne plus ultra of weapons, and they believed that whoever had superiority in these weapons would take over the world, without necessarily using them. He was afraid of a "missile gap" and took several more steps to achieve his goal of keeping up with the Soviets:


What were Russians opinions of future weaponry?


Why did von Neumann join government work?

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 as "violently anti-communist, and much more militaristic than the norm". He was quoted in 1950 remarking, "If you say why not bomb [the Soviets] tomorrow, I say, why not today? If you say today at five o'clock, I say why not one o'clock?"


How did von Neumaan describe his political ideology?


What was the project that von Neumann first participated in government?


Who was the inventor of the merge-sort algorithm?

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 still be seen on the first page of the phrase "TOP SECRET", which was written in pencil and later erased. He also worked on the philosophy of artificial intelligence with Alan Turing when the latter visited Princeton in the 1930s.


With whom did von Neumann work on the philosophy of artificial intelligence?


Where were the computations for hydrogen bomb worked out?

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 to be approximated using random numbers. His algorithm for simulating a fair coin with a biased coin is used in the "software whitening" stage of some hardware random number generators. Because using lists of "truly" random numbers was extremely slow, von Neumann developed a form of making pseudorandom numbers, using the middle-square method. Though this method has been criticized as crude, von Neumann was aware of this: he justified it as being faster than any other method at his disposal, and also noted that when it went awry it did so obviously, unlike methods which could be subtly incorrect. "Anyone who considers arithmetical methods of producing random digits is, of course, in a state of sin."


Due to slow use of random numbers what was developed?


What nullified patent claims of EDVAC designers?

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, described a computer architecture in which the data and the program are both stored in the computer's memory in the same address space. This architecture is to this day the basis of modern computer design, unlike the earliest computers that were "programmed" using a separate memory device such as a paper tape or plugboard. Although the single-memory, stored program architecture is commonly called von Neumann architecture as a result of von Neumann's paper, the architecture's description was based on the work of J. Presper Eckert and John William Mauchly, inventors of the ENIAC computer at the University of Pennsylvania.


What was the speed difference with new ENIAC?

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 old ENIAC. Some of von Neumann's early computer programs have been preserved. The next computer that von Neumann designed was the IAS machine at the Institute for Advanced Study in Princeton, New Jersey. He arranged its financing, and the components were designed and built at the RCA Research Laboratory nearby. John von Neumann recommended that the IBM 701, nicknamed the defense computer include a magnetic drum. It was a faster version of the IAS machine and formed the basis for the commercially successful IBM 704.


What were advantages for programming new ENIAC?


After the design of IAS, who built the computer?


When was stochastic computing introduced?

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 graph paper. The concept of a universal constructor was fleshed out in his posthumous work Theory of Self Reproducing Automata. Von Neumann proved that the most effective way of performing large-scale mining operations such as mining an entire moon or asteroid belt would be by using self-replicating spacecraft, taking advantage of their exponential growth. His rigorous mathematical analysis of the structure of self-replication (of the semiotic relationship between constructor, description and that which is constructed), preceded the discovery of the structure of DNA. Beginning in 1949, von Neumann's design for a self-reproducing computer program is considered the world's first computer virus, and he is considered to be the theoretical father of computer virology.


How long before stochastic computing could be implemented?


When did von NEumann develop first self reproducing computer program?


What is another name for the first self reproducing computer program?


On what computer was the first numerical weather forecast produced?

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 spreading colorants on the polar ice caps to enhance absorption of solar radiation (by reducing the albedo). thereby inducing global warming. Noting that the Earth was only 6 °F (3.3 °C) colder during the last glacial period, he noted that the burning of coal and oil "a general warming of the Earth by about one degree Fahrenheit."


In what year did von Neumann publish the paper Numerical Integration of the Barotropic Vorticity Equation


How much colder was world in last glacial age?


How quickly was von Neumann able to complete math in his head?

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 "von Neumann's speed was awe-inspiring." Israel Halperin said: "Keeping up with him was ... impossible. The feeling was you were on a tricycle chasing a racing car." Edward Teller wrote that von Neumann effortlessly outdid anybody he ever met, and said "I never could keep up with him". Teller also said "von Neumann would carry on a conversation with my 3-year-old son, and the two of them would talk as equals, and I sometimes wondered if he used the same principle when he talked to the rest of us. Most people avoid thinking if they can, some of us are addicted to thinking, but von Neumann actually enjoyed thinking, maybe even to the exclusion of everything else."


Were other mathematicians amazed by von Neumann?


How did Lothar Wolfgang Nordheim describe von Neumann?

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 in the course of a lecture I stated an unsolved problem, the chances were he'd come to me at the end of the lecture with the complete solution scribbled on a slip of paper." Halmos recounts a story told by Nicholas Metropolis, concerning the speed of von Neumann's calculations, when somebody asked von Neumann to solve the famous fly puzzle:


What did Jacob Bronowski think of von Neumann?


What did Lecturer Polya think about von Nuemann?


What did Herman Goldstone write about von NEumann?

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 original language into English. On one occasion I tested his ability by asking him to tell me how A Tale of Two Cities started. Whereupon, without any pause, he immediately began to recite the first chapter and continued until asked to stop after about ten or fifteen minutes." Ulam noted that von Neumann's way of thinking might not be visual, but more of an aural one.


Could von Neumann recall written text much later?


What did Ulam think of von Nuemann's cognitive ability?


What did Nobel Laureate Hans Bethe think of von NEumann's ability?

"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 von Neumann was probably the most influential mathematician who ever lived," wrote Miklós Rédei in "Selected Letters." James Glimm wrote: "he is regarded as one of the giants of modern mathematics". The mathematician Jean Dieudonné called von Neumann "the last of the great mathematicians", while Peter Lax described him as possessing the "most scintillating intellect of this century".


What did James Glimm have to say about von Nuemann?


What description did Peter Lax use for von Neumann?


In what year was von Neumann diagnosed with cancer?

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 significant to his mother after the family's conversion in 1929–1930. John had earlier said to his mother, "There is probably a God. Many things are easier to explain if there is than if there isn't." Von Neumann held on to his exemplary knowledge of Latin and quoted to a deathbed visitor the declamation "Judex ergo cum sedebit," and ends "Quid sum miser tunc dicturus? Quem patronum rogaturus, Cum vix iustus sit securus?" (When the judge His seat hath taken ... What shall wretched I then plead? Who for me shall intercede when the righteous scarce is freed?)


From when his mother was diagnosed with cancer, how long did she live?


How long did von Neumann survive with cancer?


Who administered the last sacrament to von Neumann?

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 Oskar Morgenstern) said they had always believed him to be "completely agnostic." "Of this deathbed conversion, Morgenstern told Heims, "He was of course completely agnostic all his life, and then he suddenly turned Catholic—it doesn't agree with anything whatsoever in his attitude, outlook and thinking when he was healthy." Father Strittmatter recalled that von Neumann did not receive much peace or comfort from it, as he still remained terrified of death.


Did the last sacrament ease von Neumann?


Was there conflict of faith and beliefs at the end of von NEumann's life?


What did Oskar Morgenstern feel about von Neumann's beliefs?


The agreement between the Nazis and the Soviets split what countries up?

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 divided territories of Romania, Poland, Lithuania, Latvia, Estonia, and Finland into German and Soviet "spheres of influence", anticipating potential "territorial and political rearrangements" of these countries. Thereafter, Germany invaded Poland on 1 September 1939. After the Soviet–Japanese ceasefire agreement took effect on 16 September, Stalin ordered his own invasion of Poland on 17 September. Part of southeastern (Karelia) and Salla region in Finland were annexed by the Soviet Union after the Winter War. This was followed by Soviet annexations of Estonia, Latvia, Lithuania, and parts of Romania (Bessarabia, Northern Bukovina, and the Hertza region). Concern about ethnic Ukrainians and Belarusians had been proffered as justification for the Soviet invasion of Poland. Stalin's invasion of Bukovina in 1940 violated the pact, as it went beyond the Soviet sphere of influence agreed with the Axis.


Which countries were taken over by the Soviets?


Who broke the agreement with the invasion of Bukovina?


The regions of Białystok, Galicia and Przemyśl were returned to what country after world war II?

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 Finland (Karelia, Petsamo), Estonia (Ingrian area and Petseri County) and Latvia (Abrene) remained part of the Russian Federation, the successor state of the Soviet Union, after 1991. Northern Bukovina, Southern Bessarabia and Hertza remain part of Ukraine.


What regions remained part of the Soviet Union?


After World War II, what regions remain part of Ukraine?


Lenin acknowledged the independence of which countries?

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 advance, Lenin and Trotsky were forced to enter into the Treaty of Brest-Litovsk, which ceded massive western Russian territories to the German Empire. After Germany's collapse, a multinational Allied-led army intervened in the Russian Civil War (1917–22).


What agreement gave Germany many regions of Russia in the first world war?


When did the russian civil war take place?


Who was to blame for communism and capitalism?

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 communism and financial capitalism, both of which they opposed. Consequently, Nazi theory held that Slavs in the Soviet Union were being ruled by "Jewish Bolshevik" masters. In 1934, Hitler himself had spoken of an inescapable battle against both Pan-Slavism and Neo-Slavism, the victory in which would lead to "permanent mastery of the world", though he stated that they would "walk part of the road with the Russians, if that will help us." The resulting manifestation of German anti-Bolshevism and an increase in Soviet foreign debts caused German–Soviet trade to dramatically decline.[b] Imports of Soviet goods to Germany fell to 223 million Reichsmarks in 1934 as the more isolationist Stalinist regime asserted power and the abandonment of post–World War I Treaty of Versailles military controls decreased Germany's reliance on Soviet imports.[clarification needed]


What reduced Germany’s need for Soviet goods?


Which political group created problems between the Soviet and German governments?


What countries prevented the Soviets from joining the Munich Conference?

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 its complete dissolution in March 1939, which as part of the appeasement of Germany conducted by Chamberlain's and Daladier's cabinets. This policy immediately raised the question of whether the Soviet Union could avoid being next on Hitler's list. The Soviet leadership believed that the West wanted to encourage German aggression in the East and that France and Britain might stay neutral in a war initiated by Germany, hoping that the warring states would wear each other out and put an end to both the Soviet Union and Nazi Germany.


Who was the English politician who appeased Germany with the take over of Czechoslovakia


The soviets suspected that Nazi-Soviet conflicts would result in what?


During conflict, what would prevent transport of materials?

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 in a number of key raw materials. After the Munich agreement, the resulting increase in German military supply needs and Soviet demands for military machinery, talks between the two countries occurred from late 1938 to March 1939. The third Soviet Five Year Plan required new infusions of technology and industrial equipment.[clarification needed] German war planners had estimated serious shortfalls of raw materials if Germany entered a war without Soviet supply.


Between german and the soviet union which country needed military machinery?


Who believed they needed a supply line from the Soviet Union to sustain another war?


Why did the Soviet government fear the governments of France and Britain?

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 attack on Germany; thus, Stalin's adherence to the collective security line was purely conditional. Britain and France believed that war could still be avoided, and that the Soviet Union, weakened by the Great Purge, could not be a main military participant, a point that many military sources were at variance with, especially Soviet victories over the Japanese Kwantung army on the Manchurian frontier. France was more anxious to find an agreement with the USSR than was Britain; as a continental power, it was more willing to make concessions, more fearful of the dangers of an agreement between the USSR and Germany. These contrasting attitudes partly explain why the USSR has often been charged with playing a double game in 1939: carrying on open negotiations for an alliance with Britain and France while secretly considering propositions from Germany.


Why did western power believe that the soviet government wouldn’t partake in another world war?


What country was at war with Japan in China prior to World War II?


Who was afraid of a pact between Germany and the Soviet governments?


Who predicted soviet aggression in the Baltic region?

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 would constitute an "indirect aggression" towards the Soviet Union. Britain opposed such proposals, because they feared the Soviets' proposed language could justify a Soviet intervention in Finland and the Baltic states, or push those countries to seek closer relations with Germany. The discussion about a definition of "indirect aggression" became one of the sticking points between the parties, and by mid-July, the tripartite political negotiations effectively stalled, while the parties agreed to start negotiations on a military agreement, which the Soviets insisted must be entered into simultaneously with any political agreement.


What month did the Tripartite discussions begin between Britain, USSR and France?


Which country is blamed for the Tripartite discussion to stagnate and fail?


Which Soviet Foreign Minister lost his job because of his favorable attitude towards the west?

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 framework of economic negotiations between the two countries, because close military and diplomatic connections, as was the case before the mid-1930s, had afterward been largely severed. In May, Stalin replaced his Foreign Minister Maxim Litvinov, who was regarded as pro-western and who was also Jewish, with Vyacheslav Molotov, allowing the Soviet Union more latitude in discussions with more parties, not only with Britain and France.


Which two countries positioned themselves to broker a deal returning to a pre-1930’s treaty with each other?


Which two countries positioned themselves to broker an new trade agreement?


In what city did the tripartite military talks occur during the month of August?

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 sticking point regarding the passage of Soviet troops through Poland if Germans attacked, and the parties waited as British and French officials overseas pressured Polish officials to agree to such terms. Polish officials refused to allow Soviet troops into Polish territory if Germany attacked; as Polish foreign minister Józef Beck pointed out, they feared that once the Red Army entered their territories, it might never leave.


Why did Poland deny the proposal of the Soviet Union protecting them from a German Attack?


Who did not want their country protected by the Soviet military?


What was the German-Soviet dividing line in regards to annexing Poland?

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 (border along the Vistula river), Latvia, Estonia, Finland, and Bessarabia in the Soviets' sphere of influence. That night, Stalin replied that the Soviets were willing to sign the pact and that he would receive Ribbentrop on 23 August.


How many days after the German-Soviet agreement were the Tripartite discussions ceased?


What other countries did the Soviet government agree to annex through the agreement with Germany?


Which Foreign Minister would agree to meet with Stalin on to sign a secret agreement?

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 entered a secret Nazi–Soviet pact. On 24 August a 10-year non-aggression pact was signed with provisions that included: consultation, arbitration if either party disagreed, neutrality if either went to war against a third power, no membership of a group "which is directly or indirectly aimed at the other".


How long was the secret agreement between Germany and the Soviets?


Part of the secret agreement between the Germans and the Soviets included a neutral diplomatic approach when?


What country held the city Vilnius prior to the inter-war period?

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 "spheres of influence". In the north, Finland, Estonia and Latvia were assigned to the Soviet sphere. Poland was to be partitioned in the event of its "political rearrangement"—the areas east of the Pisa, Narev, Vistula and San rivers going to the Soviet Union while Germany would occupy the west. Lithuania, adjacent to East Prussia, would be in the German sphere of influence, although a second secret protocol agreed to in September 1939 reassigned the majority of Lithuania to the USSR. According to the secret protocol, Lithuania would be granted the city of Vilnius – its historical capital, which was under Polish control during the inter-war period. Another clause of the treaty was that Germany would not interfere with the Soviet Union's actions towards Bessarabia, then part of Romania; as the result, Bessarabia was joined to the Moldovan ASSR, and become the Moldovan SSR under control of Moscow.


What country would reclaim the city of Vilnius?


What rivers would the soviet union claim as their own during the invasion of poland?


Who would claim Lithuania under their political umbrella?


Bessarabia eventually became under the control of which country?


Which diplomat leaked information about the secret agreements?

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 of the British–French–Soviet negotiations that had taken place for months. The Molotov–Ribbentrop Pact was received with shock by Nazi Germany's allies, notably Japan, by the Comintern and foreign communist parties, and by Jewish communities all around the world. So, that day, German diplomat Hans von Herwarth, whose grandmother was Jewish, informed Guido Relli, an Italian diplomat, and American chargé d'affaires Charles Bohlen on the secret protocol regarding vital interests in the countries' allotted "spheres of influence", without revealing the annexation rights for "territorial and political rearrangement".


Which ally of Germany was most surprised by the signing of the agreement?


How long had the tripartite discussions been taking place?


Who downplayed the contrast and recent past history between German and the Soviets?

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 that "fascism is a matter of taste". For its part, Nazi Germany also did a public volte-face regarding its virulent opposition to the Soviet Union, though Hitler still viewed an attack on the Soviet Union as "inevitable".[citation needed]


How long did the anti-Nazi propaganda machine run before the pact-signing?


A war with the USSR was considered certain according to whom?


What was the response of Kliment Voroshilov in regards to further conversations with Britain and France?

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." That day, Hitler told the British ambassador to Berlin that the pact with the Soviets prevented Germany from facing a two front war, changing the strategic situation from that in World War I, and that Britain should accept his demands regarding Poland.


Who should accept the annexation of Poland?


By accepting the deal with the USSR, Hitler admitted that it prevented what?


How did the Russians communicate to the Germans in regards to bombing civilians trying to flee cities?

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 civilian refugees on roads and carrying out a bombing campaign. The Soviet Union assisted German air forces by allowing them to use signals broadcast by the Soviet radio station at Minsk allegedly "for urgent aeronautical experiments".


How long did the Germans massacre Polish and Jewish civilians?


Why did Soviets create fake elections in Poland?

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 to liquidate the Polish state, and a German–Soviet meeting in September addressed the future structure of the "Polish region". Soviet authorities immediately started a campaign of Sovietization of the newly acquired areas. The Soviets organized staged elections, the result of which was to become a legitimization of Soviet annexation of eastern Poland.


Where did the Nazi and Russian leaders meet to discuss what to do with Poland?


Where were cooperative military parades held?


After amending the joint agreement, who received the larger portion of Lithuania?

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 Scheschupe, the "Lithuanian Strip") from the envisioned German sphere to the Soviets. On 28 September 1939, the Soviet Union and German Reich issued a joint declaration in which they declared:


What was the amended joint agreement called?


How long after the annexation of Kresy was the amendment made?


The Soviets took over and setup a fake government in what country?

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, which Finland rejected. The Soviets staged the shelling of Mainila and used it as a pretext to withdraw from the non-aggression pact. The Red Army attacked in November 1939. Simultaneously, Stalin set up a puppet government in the Finnish Democratic Republic.[clarification needed] The leader of the Leningrad Military District Andrei Zhdanov commissioned a celebratory piece from Dmitri Shostakovich, entitled "Suite on Finnish Themes" to be performed as the marching bands of the Red Army would be parading through Helsinki. After Finnish defenses surprisingly held out for over three months while inflicting stiff losses on Soviet forces, the Soviets settled for an interim peace. Finland ceded southeastern areas of Karelia (10% of Finnish territory), which resulted in approximately 422,000 Karelians (12% of Finland's population) losing their homes. Soviet official casualty counts in the war exceeded 200,000, although Soviet Premier Nikita Khrushchev later claimed the casualties may have been one million.


How long did the Finnish military last during the invasion by the soviets?


Although officially, the number of soviets wounded during the invasion of finland was around 200,000, who said the real numbers may have been closer to a million?


How many Finnish people lost their homes?


Who invaded the countries of Lithuania, Estonia and Latvia?

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 deported or killed. Elections were held with single pro-Soviet candidates listed for many positions, with resulting peoples assemblies immediately requesting admission into the USSR, which was granted by the Soviet Union. The USSR annexed the whole of Lithuania, including the Scheschupe area, which was to be given to Germany.


What region of Lithuania was to be turned over to the Nazis?


Of the three countries invaded, which lost the least amount of people through deportation or loss of life?


How did these countries become part of the USSR?


How many days after France sued for peace did the Romanians meet the requests of the USSR?

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 initially not requested by the USSR but was later occupied by force after the Romanians agreed to the initial Soviet demands. The subsequent waves of deportations began in Bessarabia and Northern Bukovina.


How many days did it take for the Romanians give into the Soviets requests?


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 regional actions about 60,000 Polish nobles, teachers, social workers, priests, judges and political activists were killed. It was continued in May 1940 when Germany launched AB-Aktion, More than 16,000 members of the intelligentsia were murdered in Operation Tannenberg alone.


How many intelligentia were killed during operation AB-Akiton?


How many Jews were forced to live within the Warsaw Ghetto?

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 perform forced labour. While ethnic Poles were subject to selective persecution, all ethnic Jews were targeted by the Reich. In the winter of 1939–40, about 100,000 Jews were thus deported to Poland. They were initially gathered into massive urban ghettos, such as 380,000 held in the Warsaw Ghetto, where large numbers died under the harsh conditions therein, including 43,000 in the Warsaw Ghetto alone. Poles and ethnic Jews were imprisoned in nearly every camp of the extensive concentration camp system in German-occupied Poland and the Reich. In Auschwitz, which began operating on 14 June 1940, 1.1 million people died.


Which group of people were considered inferior?


How many Polish people were used in labor camps?


How many people are believed to have died in Auschwitz?


How much did the transfer of the Lithuanian Strip cost the Soviet Union?

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 (31.5 million Reichsmark). The agreement formally set the border between Germany and the Soviet Union between the Igorka river and the Baltic Sea. It also extended trade regulation of the 1940 German–Soviet Commercial Agreement until August 1, 1942, increased deliveries above the levels of year one of that agreement, settled trading rights in the Baltics and Bessarabia, calculated the compensation for German property interests in the Baltic States now occupied by the Soviets and other issues. It also covered the migration to Germany within two and a half months of ethnic Germans and German citizens in Soviet-held Baltic territories, and the migration to the Soviet Union of Baltic and "White Russian" "nationals" in German-held territories.


How long did germans have to relocate from the baltic states after the amendment of secret protocols?


How long did the Russians have to relocate from the german occupied regions?


How long did the amendment extend the trade agreements?


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 elected president of the Chamber of Commerce." Beginning in September 1939, the Soviet Comintern suspended all anti-Nazi and anti-fascist propaganda, explaining that the war in Europe was a matter of capitalist states attacking each other for imperialist purposes. Western Communists acted accordingly; while before they supported protecting collective security, now they denounced Britain and France going to war.


Who was the leader of the American communist party?


Who protested the involvement of Britain and France in a war with Germany?


The western communists new rhetoric was that the war was?

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 Dimitrov,[clarification needed] and the latter sketched a new Comintern line on the war. The new line—which stated that the war was unjust and imperialist—was approved by the secretariat of the Communist International on 9 September. Thus, the various western Communist parties now had to oppose the war, and to vote against war credits. Although the French Communists had unanimously voted in Parliament for war credits on 2 September and on 19 September declared their "unshakeable will" to defend the country, on 27 September the Comintern formally instructed the party to condemn the war as imperialist. By 1 October the French Communists advocated listening to German peace proposals, and Communist leader Maurice Thorez deserted from the French Army on 4 October and fled to Russia. Other Communists also deserted from the army.


The western communists claimed the war was what?


Where did Maurice Thorez go after deserting the Army?


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 relations with the Soviet Union, whereas the English–French war bloc desires a war against the socialist Soviet Union. The Soviet people and the working people of Germany have an interest in preventing the English war plan."


Who publicly wanted peace with Soviet Union


The British army was considered to be what by Walter Ulbricbht?


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 for Communist propaganda. According to Molotov Germany had a legitimate interest in regaining its position as a great power and the Allies had started an aggressive war in order to maintain the Versailles system.


Who provides rhetoric points for the Soviet propaganda?


What was the title of Molotov’s report called?

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 Germany is nothing more, nothing less than extermination of Hitlerism. [...] There is absolutely no justification for this kind of war. The ideology of Hitlerism, just like any other ideological system, can be accepted or rejected, this is a matter of political views. But everyone grasps, that an ideology can not be exterminated by force, must not be finished off with a war."


According to Molotov, what was the goal of the west?


Under what guise does the west perform their international policing?


How much more expansive was the newest trade agreement?

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 million tons of wheat, 900,000 tons of oil, 100,000 tons of cotton, 500,000 tons of phosphates and considerable amounts of other vital raw materials, along with the transit of one million tons of soybeans from Manchuria.[citation needed] These and other supplies were being transported through Soviet and occupied Polish territories. The Soviets were to receive a naval cruiser, the plans to the battleship Bismarck, heavy naval guns, other naval gear and thirty of Germany's latest warplanes, including the Me-109 and Me-110 fighters and Ju-88 bomber. The Soviets would also receive oil and electric equipment, locomotives, turbines, generators, diesel engines, ships, machine tools and samples of German artillery, tanks, explosives, chemical-warfare equipment and other items.


What was the trade route between german and the soviet union?


What famous ship was the soviet union getting the plans for?


How many new airplanes were the soviets getting in this agreement?


What did the Germans use to avoid British blockades?

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 Northern Sea Route for both cargo ships and raiders (though only the commerce raider Komet used the route before the German invasion), which forced Britain to protect sea lanes in both the Atlantic and the Pacific.


Which oceans did the sub base provide access to?


Who wanted to know the moment an anti-german bloc was to form?

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 reassurances to the Germans, and the Germans' mistrust, intensified. On June 16, as the Soviets invaded Lithuania, but before they had invaded Latvia and Estonia, Ribbentrop instructed his staff "to submit a report as soon as possible as to whether in the Baltic States a tendency to seek support from the Reich can be observed or whether an attempt was made to form a bloc."


Why did the Germans distrust the soviet agenda?


What caused distrust between the German and Soviet governments?


Who stopped the trade because of a disagreement involving Romania?

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 with the West might end quickly after France signed an armistice. The suspension created significant resource problems for Germany. By the end of August, relations improved again as the countries had redrawn the Hungarian and Romanian borders, settled some Bulgarian claims and Stalin was again convinced that Germany would face a long war in the west with Britain's improvement in its air battle with Germany and the execution of an agreement between the United States and Britain regarding destroyers and bases. However, in late August, Germany arranged its own occupation of Romania, targeting oil fields. The move raised tensions with the Soviets, who responded that Germany was supposed to have consulted with the Soviet Union under Article III of the Molotov–Ribbentrop Pact.


What regions were redrawn in effort to improve relations between Germany and the Soviets?


What countries agreed to a tripartisan agreement?

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 Union to join the Axis and potentially enjoy the spoils of the pact. After negotiations during November 1940 on where to extend the USSR's sphere of influence, Hitler broke off talks and continued planning for the eventual attempts to invade the Soviet Union.


Which Foreign Minister proposed that the Soviets should join this agreement of axis powers?


Who would the axis powers oppose in the new agreement?


Who was planning an invasion of the Soviet Union?

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. Stalin felt that there was a growing split in German circles about whether Germany should initiate a war with the Soviet Union. Stalin did not know that Hitler had been secretly discussing an invasion of the Soviet Union since summer 1940, and that Hitler had ordered his military in late 1940 to prepare for war in the east regardless of the parties' talks of a potential Soviet entry as a fourth Axis Power.


Who did the Soviet Union agree to remain neutral with when they signed a treaty on the 13th of April?


Where did the German attack on Soviet forces occur?

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 ordered no 'full-scale' mobilization of forces although the mobilization was ongoing. After the launch of the invasion, the territories gained by the Soviet Union as a result of the Molotov–Ribbentrop Pact were lost in a matter of weeks. Within six months, the Soviet military had suffered 4.3 million casualties, and Germany had captured three million Soviet prisoners. The lucrative export of Soviet raw materials to Nazi Germany over the course of the Nazi–Soviet economic relations (1934–41) continued uninterrupted until the outbreak of hostilities. The Soviet exports in several key areas enabled Germany to maintain its stocks of rubber and grain from the first day of the invasion until October 1941.


How many Soviet military members died within the first six months of the war between the two countries?


How many Soviet prisoners did german take within the first six months of war between the two countries?


How long did it take to capture regions of the world that were once occupied by soviets once the initial attack occurred?


How many pages of secret documents were microfilmed?

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 were evacuated to Thuringia at the end of the war, Karl von Loesch, a civil servant who had worked for the chief interpreter Paul Otto Schmidt, was entrusted with these microfilm copies. He eventually received orders to destroy the secret documents but decided to bury the metal container with the microfilms as a personal insurance for his future well-being. In May 1945, von Loesch approached the British Lt. Col. Robert C. Thomson with the request to transmit a personal letter to Duncan Sandys, Churchill's son-in-law. In the letter, von Loesch revealed that he had knowledge of the documents' whereabouts but expected preferential treatment in return. Colonel Thomson and his American counterpart Ralph Collins agreed to transfer von Loesch to Marburg in the American zone if he would produce the microfilms. The microfilms contained a copy of the Non-Aggression Treaty as well as the Secret Protocol. Both documents were discovered as part of the microfilmed records in August 1945 by the State Department employee Wendell B. Blancke, head of a special unit called "Exploitation German Archives" (EGA).


What did Wendell B. Blancke investigate at the end of the war?


Near the end of the war, where the did some of the german command flee to?


Why did Karl von Loesch bury the microfilm?


Where was Karl von Löesch transferred to after he turned over the documents?


Who printed the secret German-Soviet treaty in Britain?

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 decision to publish the key documents on German–Soviet relations, including the treaty and protocol, had been taken already in spring 1947. Sontag and Beddie prepared the collection throughout the summer of 1947. In November 1947, President Truman personally approved the publication but it was held back in view of the Foreign Ministers Conference in London scheduled for December. Since negotiations at that conference did not prove constructive from an American point of view, the document edition was sent to press. The documents made headlines worldwide. State Department officials counted it as a success: "The Soviet Government was caught flat-footed in what was the first effective blow from our side in a clear-cut propaganda war."


Which world leader favored the publication of Nazi-Soviet Relations to be printed?


Where was the Foreign Ministers conference held?


Who put the Nazi-Soviet Relations publication together?


What was the description of the Soviet government in the world press in regards to the treaty and subsequent breaking of the treaty by germany?


What year was Joseph Stalin’s version of the pact published?

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 division of the world, without mentioning the Soviet offer to join the Axis. That version persisted, without exception, in historical studies, official accounts, memoirs and textbooks published in the Soviet Union until the Soviet Union's dissolution.


What was the Soviet response to the Nazi-Soviet Relations publication


How long did Stalins version of what happened between the Germans and the Soviets last?


Who created an investigation into whether or not the Soviet-German Pact happened?

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 protocol had existed and revealed its findings to the Congress of People's Deputies of the Soviet Union. As a result, the Congress passed the declaration confirming the existence of the secret protocols, condemning and denouncing them. Both successor-states of the pact parties have declared the secret protocols to be invalid from the moment they were signed. The Federal Republic of Germany declared this on September 1, 1989 and the Soviet Union on December 24, 1989, following an examination of the microfilmed copy of the German originals.


Which states have argued that the Soviet-German Pact was invalid from the inception?


Which government agency received the news that the Soviet-German Pact had existed?


Who was ordered to remove the Jews from the Ministry?

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 to create an anti-fascist coalition, association with the doctrine of collective security with France and Britain, and pro-Western orientation by the standards of the Kremlin, his dismissal indicated the existence of a Soviet option of rapprochement with Germany.[f] Likewise, Molotov's appointment served as a signal to Germany that the USSR was open to offers. The dismissal also signaled to France and Britain the existence of a potential negotiation option with Germany. One British official wrote that Litvinov's disappearance also meant the loss of an admirable technician or shock-absorber, while Molotov's "modus operandi" was "more truly Bolshevik than diplomatic or cosmopolitan." Carr argued that the Soviet Union's replacement of Foreign Minister Litvinov with Molotov on May 3, 1939 indicated not an irrevocable shift towards alignment with Germany, but rather was Stalin's way of engaging in hard bargaining with the British and the French by appointing a proverbial hard man, namely Molotov, to the Foreign Commissariat. Historian Albert Resis stated that the Litvinov dismissal gave the Soviets freedom to pursue faster-paced German negotiations, but that they did not abandon British–French talks. Derek Watson argued that Molotov could get the best deal with Britain and France because he was not encumbered with the baggage of collective security and could negotiate with Germany. Geoffrey Roberts argued that Litvinov's dismissal helped the Soviets with British–French talks, because Litvinov doubted or maybe even opposed such discussions.


Who gave the order to remove the Jews from the Ministry?


Who believed that the firing of Litvinov allowed the Soviets to quicker negotiations with Germany?


Who believed that the hiring of Molotov would result in a better deal with the western countries?


Edward Carr believes that in a war between Germany and the Soviet Union, who else would have been participating?

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."[page needed] According to Carr, an important advantage was that "if Soviet Russia had eventually to fight Hitler, the Western Powers would already be involved."[page needed] However, during the last decades, this view has been disputed. Historian Werner Maser stated that "the claim that the Soviet Union was at the time threatened by Hitler, as Stalin supposed ... is a legend, to whose creators Stalin himself belonged. In Maser's view, "neither Germany nor Japan were in a situation [of] invading the USSR even with the least perspective [sic] of success," and this could not have been unknown to Stalin. Carr further stated that, for a long time, the primary motive of Stalin's sudden change of course was assumed to be the fear of German aggressive intentions.


Who believes that the Soviet Unions was afraid of Germany?


The pact according to Edward Carr’s view was to provide what between Germany and the Soviet Union?


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 by Albert L. Weeks.[page needed] Claims by Suvorov that Stalin planned to invade Germany in 1941 are debated by historians with, for example, David Glantz opposing such claims, while Mikhail Meltyukhov supports them.[citation needed] The authors of The Black Book of Communism consider the pact a crime against peace and a "conspiracy to conduct war of aggression."


What is the claim the pact promoted, purported by the The Black Book of Communism?


Who doesn’t believe that Joseph Stalin had plans to invade Germany?


What was a capacitor originally known as?

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 store energy by becoming polarized). The conductors can be thin films, foils or sintered beads of metal or conductive electrolyte, etc. The nonconducting dielectric acts to increase the capacitor's charge capacity. Materials commonly used as dielectrics include glass, ceramic, plastic film, air, vacuum, paper, mica, and oxide layers. Capacitors are widely used as parts of electrical circuits in many common electrical devices. Unlike a resistor, an ideal capacitor does not dissipate energy. Instead, a capacitor stores energy in the form of an electrostatic field between its plates.


How many electrical conductors, or plates, do all capacitors contain at a minimum?


What is the name of the insulator in all capacitors that can store energy by becoming polarized?


In what form does a capacitor store energy?


Where is the energy stored by a capacitor located?


When does an electric field develop across the dielectric?

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 sufficient amount of time, no current can flow through the capacitor. However, if a time-varying voltage is applied across the leads of the capacitor, a displacement current can flow.


Under what condition can a displacement current flow in a capacitor?


What is an example of when there exists a potential difference across the conductors?


What happens to the current when a battery has been attached to a capacitor for an adequate amount of time?


How do charges accumulate on each plate of a capacitor after an electric field has developed across the dielectric?


Who first discovered the basic properties of capacitors?

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 mechanism were incorrectly identified at the time). Von Kleist found that touching the wire resulted in a powerful spark, much more painful than that obtained from an electrostatic machine. The following year, the Dutch physicist Pieter van Musschenbroek invented a similar capacitor, which was named the Leyden jar, after the University of Leiden where he worked. He also was impressed by the power of the shock he received, writing, "I would not take a second shock for the kingdom of France."


When were the basic properties of capacitors first discovered?


In the original experiment in which the properties of capacitors were discovered, what component acted as the dielectric?


Besides the scientist's hand, what other component of the experiment in which the basic properties of capacitors were discovered acted as the second conductor?


What was the name of the Dutch physicist who invented the Leyden Jar?


Who was the first person to connect several Leyden jars in parallel?

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", (denoting the increasing of power with a row of similar units as in a battery of cannon), subsequently applied to clusters of electrochemical cells. Leyden jars were later made by coating the inside and outside of jars with metal foil, leaving a space at the mouth to prevent arcing between the foils.[citation needed] The earliest unit of capacitance was the jar, equivalent to about 1.11 nanofarads.


Where did Benjamin Franklin believe the charge was stored in Leyden jars?


How many nanofarads did the earliest unit of capacitance equate to?


Why was a gap left at the mouth of Leyden jars?


Besides porcelain, paper and mica, what other non conductive material was used as an insulator?

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 paper between strips of metal, and rolling the result into a cylinder were commonly used in the late 19century; their manufacture started in 1876, and they were used from the early 20th century as decoupling capacitors in telecommunications (telephony).


For what use were non conductive materials used in the first capacitors?


What was layered between strips of metal in order to create paper capacitors?


When were paper capacitors first manufactured?


What other use did paper capacitors serve in the telecommunications industry?


Who invented the first electrolytic capacitor?

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." Solid electrolyte tantalum capacitors were invented by Bell Laboratories in the early 1950s as a miniaturized and more reliable low-voltage support capacitor to complement their newly invented transistor.


In what sort of electrolyte does the oxide layer on an aluminum anode remain stable?


In what year was the patent filed for an electric liquid capacitor?


What sort of capacitors were created by Bell Labs in the 1950's?


Why did Bell labs create their new type of capacitor?


What are electric double-layer capacitors called today?

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 of electrolytic capacitors. Because the double layer mechanism was not known by him at the time, he wrote in the patent: "It is not known exactly what is taking place in the component if it is used for energy storage, but it leads to an extremely high capacity.".


When were low voltage electrolytic capacitors with porous carbon electrodes invented?


Who invented low voltage electrolytic capacitors with porous carbon electrodes?


In what part of the capacitor did Becker believe the charge was being stored?


In what component of electrolytic capacitors did Becker believe was similar to the porous carbon electrodes?


What type of area is between the two conductors in a capacitor?

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 conductors. A capacitor is assumed to be self-contained and isolated, with no net electric charge and no influence from any external electric field. The conductors thus hold equal and opposite charges on their facing surfaces, and the dielectric develops an electric field. In SI units, a capacitance of one farad means that one coulomb of charge on each conductor causes a voltage of one volt across the device.


What is the name given to the area between two conductors in a capacitor?


What net electric charge are capacitors assumed to have?


What type of charges do conductors hold on their facing surfaces?


What region within a capacitor develops an electric field?


What is the definition of the current I(t) through any component in an electric circuit?

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, resulting in an electron depletion and consequent positive charge on one electrode that is equal and opposite to the accumulated negative charge on the other. Thus the charge on the electrodes is equal to the integral of the current as well as proportional to the voltage, as discussed above. As with any antiderivative, a constant of integration is added to represent the initial voltage V(t0). This is the integral form of the capacitor equation:


For each electron that departs the positive plate, how many electrons build up on the negative plate?


To what is the charge on the electrodes of a capacitor equal to?


To what is the charge on the electrodes of a capacitor proportional to?


When calculating the integral to determine the charge on the electrodes of a capacitor, what does the constant of integration that must be added represent?


In an ideal model of a capacitor, what is the value that describes the permittivity of the dielectric?

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 their surface. Assuming that the length and width of the plates are much greater than their separation d, the electric field near the centre of the device will be uniform with the magnitude E = ρ/ε. The voltage is defined as the line integral of the electric field between the plates


What equation describes the charge density for an ideal model of a capacitor?


In an ideal model of a capacitor, what must be assumed about the size of the plates?


Close to the middle of the capacitor, what equation describes the magnitude of the electric field?


What does the line integral of the electric field between the plates of a capacitor represent?


What is a function of the amount of dielectric, the strength of dielectric and its permittivity?

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 smaller than both the length and width of the plates. In addition, these equations assume that the electric field is entirely concentrated in the dielectric between the plates. In reality there are fringing fields outside the dielectric, for example between the sides of the capacitor plates, which will increase the effective capacitance of the capacitor. This is sometimes called parasitic capacitance. For some simple capacitor geometries this additional capacitance term can be calculated analytically. It becomes negligibly small when the ratios of plate width to separation and length to separation are large.


If the plate area and separation distance are altered while keeping the amount of dielectric the same, what effect is had on the maximum energy of the capacitor?


In a realistic model of a capacitor, where else besides between the dielectric between the conductors might an electric field be found?


When an electric field exists between the sides of the plates as well as in within the dielectric, what effect is had on the effective capacitance of the capacitor?


When the ratios of plate length and width to separation distance are large, what size is the parasitic capacitance?


What characteristic can leakage current and parasitic effects be assumed to have in the equation for a realistic capacitor?

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 be applied. In other cases, such as with breakdown voltage, the effect is non-linear and normal (i.e., linear) network analysis cannot be used, the effect must be dealt with separately. There is yet another group, which may be linear but invalidate the assumption in the analysis that capacitance is a constant. Such an example is temperature dependence. Finally, combined parasitic effects such as inherent inductance, resistance, or dielectric losses can exhibit non-uniform behavior at variable frequencies of operation.


What sort of components can be added to the equivalent circuit of a capacitor in order to deal with leakage current and parasitic effects?


Upon dealing with leakage current and parasitic effects in a realistic model of a capacitor, what sort of methods can then be applied?


What sort of analysis cannot be used in cases of voltage breakdown in modelling a capacitor?


What causes the assumption of constant capacitance to fail even if the effect is linear in nature?


What order is the breakdown field strength for air dielectric capacitors of?

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 limited. Typical ratings for capacitors used for general electronics applications range from a few volts to 1 kV. As the voltage increases, the dielectric must be thicker, making high-voltage capacitors larger per capacitance than those rated for lower voltages. The breakdown voltage is critically affected by factors such as the geometry of the capacitor conductive parts; sharp edges or points increase the electric field strength at that point and can lead to a local breakdown. Once this starts to happen, the breakdown quickly tracks through the dielectric until it reaches the opposite plate, leaving carbon behind and causing a short (or relatively low resistance) circuit. The results can be explosive as the short in the capacitor draws current from the surrounding circuitry and dissipates the energy.


Of what order is the breakdown field strength for mica dielectric capacitors?


In what way is the dielectric used in order to cause the absolute breakdown voltage of capacitors to be limited?


What is one factor that critically affects the breakdown voltage of the capacitor?


What is the difference in the physical attributes of the dielectric used in high voltage capacitors compared to low voltage capacitors?


What name is given to the AC component of an applied source having either constant or alternating frequency?

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 resistive supply lines or the electrolyte in the capacitor. The equivalent series resistance (ESR) is the amount of internal series resistance one would add to a perfect capacitor to model this. Some types of capacitors, primarily tantalum and aluminum electrolytic capacitors, as well as some film capacitors have a specified rating value for maximum ripple current.


What is one cause of dielectric losses in a capacitor?


What is another cause of dielectric losses in a capacitor?


What is the name given to the amount of internal series resistance needed to add to an ideal capacitor model in order to represent the heat generated by dielectric losses?


What is one type of capacitor that has a specified rating value for maximum ripple current?


What value of some capacitors decreases with age?

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 may be reversed by heating the component above the Curie point. Aging is fastest near the beginning of life of the component, and the device stabilizes over time. Electrolytic capacitors age as the electrolyte evaporates. In contrast with ceramic capacitors, this occurs towards the end of life of the component.


What causes the decrease of capacitance in ceramic capacitors as they age?


What is one of the most important aging factors in capacitors?


What is another important factor which governs how a capacitor ages?


At what point can the aging effect of a capacitor be reversed if the component is heated beyond?


What is the effect called when capacitors absorb sound waves?

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 especially problematic in audio applications, potentially causing feedback or unintended recording. In the reverse microphonic effect, the varying electric field between the capacitor plates exerts a physical force, moving them as a speaker. This can generate audible sound, but drains energy and stresses the dielectric and the electrolyte, if any.


What value of a capacitor is varied when vibration moves the conducting plates?


What sort of current is induced when the capacitance of a capacitor is altered?


In what type of applications is piezeoelectricity especially problematic?


What is it called when a changing electric field existing between the conductive plates of a capacitor physically moves them?


What is one type of circuit in which voltage and current reversal are affected by damping?

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 tend to oscillate and may reverse direction several times, with each peak being lower than the previous, until the system reaches an equilibrium. This is often referred to as ringing. In comparison, critically damped or over-damped systems usually do not experience a voltage reversal. Reversal is also encountered in AC circuits, where the peak current will be equal in each direction.


What is another type of circuit in which voltage and current reversal are affected by damping?


Under what condition does voltage reversal occur in RLC circuits?


What is formed between the inductance and the capacitance when the current and the voltage switch direction?


When a system is over-damped, what does it typically not experience?


What percentage of voltage reversal does an AC circuit experience?

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 heating of both the dielectric and the conductors, and can dramatically shorten the life expectancy of the capacitor. Reversal ratings will often affect the design considerations for the capacitor, from the choice of dielectric materials and voltage ratings to the types of internal connections used.


What does voltage reversal create in the dielectric of a capacitor?


What percentage of voltage reversal will an under damped DC circuit experience?


What does excess electric field present in the dielectric lead to?


When designing a capacitor, what is an important rating to consider?


After discharging and disconnecting a capacitor, what causes it to develop a voltage?

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 and hold circuits or timing circuits. The level of absorption depends on many factors, from design considerations to charging time, since the absorption is a time-dependent process. However, the primary factor is the type of dielectric material. Capacitors such as tantalum electrolytic or polysulfone film exhibit very high absorption, while polystyrene or Teflon allow very small levels of absorption. In some capacitors where dangerous voltages and energies exist, such as in flashtubes, television sets, and defibrillators, the dielectric absorption can recharge the capacitor to hazardous voltages after it has been shorted or discharged. Any capacitor containing over 10 joules of energy is generally considered hazardous, while 50 joules or higher is potentially lethal. A capacitor may regain anywhere from 0.01 to 20% of its original charge over a period of several minutes, allowing a seemingly safe capacitor to become surprisingly dangerous.


What does the process of dielectric absorption in a capacitor depend on?


What level of dielectric absorption would a tantalum electrolytic capacitor display?


What level of dielectric absorption would a Teflon capacitor exhibit?


What amount of energy must a capacitor contain in order to be generally considered dangerous?


With what value is a resistor in parallel with a capacitor equal to?

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 capacitors are used to conduct a varying signal from the plate of one tube to the grid circuit of the next stage. A leaky capacitor can cause the grid circuit voltage to be raised from its normal bias setting, causing excessive current or signal distortion in the downstream tube. In power amplifiers this can cause the plates to glow red, or current limiting resistors to overheat, even fail. Similar considerations apply to component fabricated solid-state (transistor) amplifiers, but owing to lower heat production and the use of modern polyester dielectric barriers this once-common problem has become relatively rare.


What can cause excessive leakage in a capacitor?


What sort of capacitors are used to carry a varying signal from the conductive plate of one tube to the grid circuit of the next stage?


What type of capacitor can cause signal distortion in the downstream tube?


If the grid circuit voltage is increased beyond its regular bias setting, what can happen to the conductive plates in power amplifiers?


What do many capacitors contain that raises the capacitance?

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 to the atmosphere were commonly used in radio tuning circuits. Later designs use polymer foil dielectric between the moving and stationary plates, with no significant air space between them.


What sort of dielectric is used in low capacitance devices?


What sort of capacitors have traditionally been used in radio tuning circuits?


How did the capacitor traditionally used in radio tuning circuits change over time?


What did the later designs of capacitors used in radio tuning circuits no longer have?


What benefit is offered by solid state paper capacitors?

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 better stability and ageing performance, which makes them useful in timer circuits, although they may be limited to low operating temperatures and frequencies. Ceramic capacitors are generally small, cheap and useful for high frequency applications, although their capacitance varies strongly with voltage and they age poorly. They are broadly categorized as class 1 dielectrics, which have predictable variation of capacitance with temperature or class 2 dielectrics, which can operate at higher voltage. Glass and mica capacitors are extremely reliable, stable and tolerant to high temperatures and voltages, but are too expensive for most mainstream applications. Electrolytic capacitors and supercapacitors are used to store small and larger amounts of energy, respectively, ceramic capacitors are often used in resonators, and parasitic capacitance occurs in circuits wherever the simple conductor-insulator-conductor structure is formed unintentionally by the configuration of the circuit layout.


What type of capacitor has mostly replaced solid state paper capacitors?