Answer: Hans von Herwarth

Context: 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".

Question: Which diplomat leaked information about the secret agreements?


Answer: Japan

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


Answer: place for months

Question: How long had the tripartite discussions been taking place?


Answer: Molotov

Context: 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]

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


Answer: a decade

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


Answer: Hitler

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


Answer: no useful purpose

Context: 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.

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


Answer: Britain

Question: Who should accept the annexation of Poland?


Answer: facing a two front war

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


Answer: signals broadcast by the Soviet radio

Context: 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".

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


Answer: 1 September

Question: What day did German invade Poland?


Answer: month

Question: How long did the Germans massacre Polish and Jewish civilians?


Answer: legitimization of Soviet annexation of eastern Poland

Context: 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.

Question: Why did Soviets create fake elections in Poland?


Answer: Brest-Litovsk

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


Answer: Lvov and Brest-Litovsk

Question: Where were cooperative military parades held?


Answer: Germany

Context: 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:

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


Answer: German–Soviet Treaty of Friendship, Cooperation and Demarcation

Question: What was the amended joint agreement called?


Answer: Eleven days

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


Answer: Finnish Democratic Republic

Context: 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.

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


Answer: over three months

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


Answer: Soviet Premier Nikita Khrushchev

Question: 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?


Answer: 422,000

Question: How many Finnish people lost their homes?


Answer: Soviet NKVD

Context: 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.

Question: Who invaded the countries of Lithuania, Estonia and Latvia?


Answer: Scheschupe area

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


Answer: Latvia

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


Answer: Elections were held with single pro-Soviet candidates

Question: How did these countries become part of the USSR?


Answer: 6

Context: 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.

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


Answer: June

Question: What month did France sue for peace?


Answer: Two days

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


Answer: Polish nobles, teachers, social workers, priests, judges and political activists

Context: 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.

Question: Who were the “intelligentia?”


Answer: fall of 1939 till spring of 1940

Question: How long did liquidation occur?


Answer: 16,000 members

Question: How many intelligentia were killed during operation AB-Akiton?


Answer: 380,000

Context: 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.

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


Answer: 43,000

Question: How many Jews died in the Warsa Ghetto?


Answer: Poles and other Slavs

Question: Which group of people were considered inferior?


Answer: Between 1 and 2.5 million Polish citizens

Question: How many Polish people were used in labor camps?


Answer: 1.1 million people

Question: How many people are believed to have died in Auschwitz?


Answer: 7.5 million dollars (31.5 million Reichsmark)

Context: 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.

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


Answer: two and a half months

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


Answer: two and a half months

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


Answer: until August 1, 1942

Question: How long did the amendment extend the trade agreements?


Answer: Herbert Biberman

Context: 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.

Question: Who was part of Hollywood Ten?


Answer: Earl Browder

Question: Who was the leader of the American communist party?


Answer: Western Communists

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


Answer: the war was unjust and imperialist

Context: 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.

Question: The western communists new rhetoric was that the war was?


Answer: the war was unjust and imperialist

Question: The western communists claimed the war was what?


Answer: war credits

Question: French communists voted for what?


Answer: fled to Russia

Question: Where did Maurice Thorez go after deserting the Army?


Answer: English–French war bloc

Context: 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."

Question: Who wanted war with the Soviet Union?


Answer: German government

Question: Who publicly wanted peace with Soviet Union


Answer: the most reactionary force in the world

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


Answer: Britain and France

Context: 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.

Question: Who refused a German-Soviet peace plan?


Answer: to maintain the Versailles system.

Question: Why was the west creating a war?


Answer: Molotov

Question: Who provides rhetoric points for the Soviet propaganda?


Answer: On the Foreign Policy of the Soviet Union

Context: 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."

Question: What was the title of Molotov’s report called?


Answer: extermination of Hitlerism

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


Answer: defending democracy

Question: Under what guise does the west perform their international policing?


Answer: was over four times larger

Context: 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.

Question: How much more expansive was the newest trade agreement?


Answer: occupied Polish territories

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


Answer: Manchuria

Question: Where were the soybeans coming from?


Answer: the battleship Bismarck

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


Answer: thirty

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


Answer: a submarine base

Context: 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.

Question: What did the Germans use to avoid British blockades?


Answer: northern Soviet Union near Murmansk

Question: Where was the sub base located?


Answer: both the Atlantic and the Pacific

Question: Which oceans did the sub base provide access to?


Answer: Ribbentrop

Context: 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."

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


Answer: Stalin's invasions were a severe irritant

Question: Why did the Germans distrust the soviet agenda?


Answer: Stalin's invasions were a severe irritant to Berlin

Question: What caused distrust between the German and Soviet governments?


Answer: Soviet Union

Context: 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.

Question: Who stopped the trade because of a disagreement involving Romania?


Answer: Hungarian and Romanian borders

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


Answer: Germany

Question: Who started refining Romanian oil?


Answer: Germany entered a Tripartite Pact with Japan and Italy

Context: 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.

Question: What countries agreed to a tripartisan agreement?


Answer: Ribbentrop

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


Answer: Britain and the USA

Question: Who would the axis powers oppose in the new agreement?


Answer: Hitler

Context: 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.

Question: Who was planning an invasion of the Soviet Union?


Answer: Japan

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


Answer: reinforce a public affection for Germany

Question: Why did Stalin sign the pact?


Answer: Soviet positions in eastern Poland

Context: 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.

Question: Where did the German attack on Soviet forces occur?


Answer: 4.3 million casualties

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


Answer: three million Soviet prisoners

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


Answer: matter of weeks

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


Answer: 9,800 pages

Context: 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).

Question: How many pages of secret documents were microfilmed?


Answer: Exploitation German Archives

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


Answer: Thuringia

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


Answer: personal insurance for his future well-being

Question: Why did Karl von Loesch bury the microfilm?


Answer: the American zone

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


Answer: the Manchester Guardian

Context: 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."

Question: Who printed the secret German-Soviet treaty in Britain?


Answer: President Truman

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


Answer: London

Question: Where was the Foreign Ministers conference held?


Answer: Raymond J. Sontag and James S. Beddie

Question: Who put the Nazi-Soviet Relations publication together?


Answer: flat-footed

Question: 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?


Answer: 1948

Context: 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.

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


Answer: Falsifiers of History

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


Answer: until the Soviet Union's dissolution

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


Answer: Mikhail Gorbachev, Alexander Nikolaevich Yakovlev

Context: 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.

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


Answer: Both successor-states of the pact parties

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


Answer: Congress of People's Deputies of the Soviet Union

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


Answer: Molotov

Context: 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.

Question: Who was ordered to remove the Jews from the Ministry?


Answer: Stalin

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


Answer: Derek Watson

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


Answer: Geoffrey Roberts

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


Answer: the Western Powers would already be involved

Context: 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.

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


Answer: Historian Werner Maser

Question: Who believes that the Soviet Unions was afraid of Germany?


Answer: a line of defense against

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


Answer: Viktor Suvorov

Context: 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."

Question: Who was skeptical of Stalin’s policies?


Answer: a "conspiracy to conduct war of aggression."

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


Answer: David Glantz

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


Answer: a condenser

Context: 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.

Question: What was a capacitor originally known as?


Answer: two electrical conductors

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


Answer: a dielectric

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


Answer: the form of an electrostatic field

Question: In what form does a capacitor store energy?


Answer: between its plates

Question: Where is the energy stored by a capacitor located?


Answer: When there is a potential difference across the conductors

Context: 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.

Question: When does an electric field develop across the dielectric?


Answer: if a time-varying voltage is applied across the leads

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


Answer: when a capacitor is attached across a battery

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


Answer: no current can flow through the capacitor

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


Answer: positive charge +Q to collect on one plate and negative charge −Q to collect on the other

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


Answer: Ewald Georg von Kleist

Context: 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."

Question: Who first discovered the basic properties of capacitors?


Answer: In October 1745

Question: When were the basic properties of capacitors first discovered?


Answer: a hand-held glass jar

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


Answer: the water acted as conductors

Question: 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?


Answer: Pieter van Musschenbroek

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


Answer: Daniel Gralath

Context: 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.

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


Answer: stored on the glass

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


Answer: Benjamin Franklin

Question: Who coined the term "battery"?


Answer: 1.11 nanofarads

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


Answer: to prevent arcing between the foils

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


Answer: glass

Context: 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).

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


Answer: as the dielectric

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


Answer: strip of impregnated paper

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


Answer: in 1876

Question: When were paper capacitors first manufactured?


Answer: as decoupling capacitors

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


Answer: Charles Pollak

Context: 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.

Question: Who invented the first electrolytic capacitor?


Answer: a neutral or alkaline electrolyte

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


Answer: In 1896

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


Answer: Solid electrolyte tantalum capacitors

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


Answer: to complement their newly invented transistor

Question: Why did Bell labs create their new type of capacitor?


Answer: Supercapacitors

Context: 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.".

Question: What are electric double-layer capacitors called today?


Answer: In 1957

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


Answer: H. Becker

Question: Who invented low voltage electrolytic capacitors with porous carbon electrodes?


Answer: in the carbon pores

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


Answer: the pores of the etched foils

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


Answer: a non-conductive region

Context: 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.

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


Answer: the dielectric

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


Answer: no net electric charge

Question: What net electric charge are capacitors assumed to have?


Answer: equal and opposite charges

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


Answer: the dielectric

Question: What region within a capacitor develops an electric field?


Answer: the rate of flow of a charge Q(t) passing through it

Context: 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:

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


Answer: one electron accumulates on the negative plate

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


Answer: the integral of the current

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


Answer: proportional to the voltage

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


Answer: the initial voltage V(t0)

Question: 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?


Answer: permittivity ε

Context: 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

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


Answer: ±ρ = ±Q/A

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


Answer: much greater than their separation d

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


Answer: E = ρ/ε

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


Answer: The voltage

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


Answer: The maximum energy

Context: 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.

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


Answer: no change of the maximum amount of energy

Question: 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?


Answer: fringing fields outside the dielectric

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


Answer: will increase the effective capacitance

Question: 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?


Answer: negligibly small

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


Answer: can be assumed to be linear

Context: 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.

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


Answer: virtual components

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


Answer: The usual methods of network analysis

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


Answer: normal (i.e., linear) network analysis cannot be used

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


Answer: temperature dependence

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


Answer: of the order 2 to 5 MV/m

Context: 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.

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


Answer: 100 to 300 MV/m

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


Answer: The dielectric is used in very thin layers

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


Answer: the geometry of the capacitor conductive parts

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


Answer: the dielectric must be thicker

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


Answer: Ripple current

Context: 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.

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


Answer: changing field strength

Question: What is one cause of dielectric losses in a capacitor?


Answer: current flow across the slightly resistive supply lines or the electrolyte

Question: What is another cause of dielectric losses in a capacitor?


Answer: equivalent series resistance (ESR)

Question: 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?


Answer: aluminum electrolytic capacitors

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


Answer: The capacitance

Context: 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.

Question: What value of some capacitors decreases with age?


Answer: degradation of the dielectric

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


Answer: The type of dielectric

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


Answer: ambient operating and storage temperatures

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


Answer: the Curie point

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


Answer: microphonic effect

Context: 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.

Question: What is the effect called when capacitors absorb sound waves?


Answer: the capacitance

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


Answer: AC current

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


Answer: audio applications

Question: In what type of applications is piezeoelectricity especially problematic?


Answer: the reverse microphonic effect

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


Answer: DC circuits

Context: 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.

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


Answer: pulsed circuits

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


Answer: under-damped

Question: Under what condition does voltage reversal occur in RLC circuits?


Answer: a harmonic oscillator

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


Answer: a voltage reversal

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


Answer: 100% voltage reversal

Context: 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.

Question: What percentage of voltage reversal does an AC circuit experience?


Answer: excess electric fields

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


Answer: less than 100%

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


Answer: heating of both the dielectric and the conductors

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


Answer: Reversal ratings

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


Answer: hysteresis in the dielectric

Context: 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.

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


Answer: time-dependent

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


Answer: very high absorption

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


Answer: very small levels of absorption

Question: What level of dielectric absorption would a Teflon capacitor exhibit?


Answer: over 10 joules of energy

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


Answer: Leakage

Context: 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.

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


Answer: Constant exposure to heat

Question: What can cause excessive leakage in a capacitor?


Answer: interstage coupling capacitors

Question: 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?


Answer: A leaky capacitor

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


Answer: cause the plates to glow red

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


Answer: a dielectric spacer

Context: 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.

Question: What do many capacitors contain that raises the capacitance?


Answer: a vacuum

Question: What sort of dielectric is used in low capacitance devices?


Answer: Variable capacitors

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


Answer: use polymer foil dielectric between the moving and stationary plates

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


Answer: no significant air space

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


Answer: relatively high voltage performance

Context: 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.

Question: What benefit is offered by solid state paper capacitors?


Answer: plastic film capacitors

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


Answer: timer circuits

Question: What sort of circuit are plastic capacitors especially useful for?


Answer: Glass

Question: What is one type of reliable capacitor that is resistant to temperature and voltage changes?


Answer: mica capacitors

Question: What is another type of reliable capacitor that is resistant to temperature and voltage changes?


Answer: aluminum

Context: Electrolytic capacitors use an aluminum or tantalum plate with an oxide dielectric layer. The second electrode is a liquid electrolyte, connected to the circuit by another foil plate. Electrolytic capacitors offer very high capacitance but suffer from poor tolerances, high instability, gradual loss of capacitance especially when subjected to heat, and high leakage current. Poor quality capacitors may leak electrolyte, which is harmful to printed circuit boards. The conductivity of the electrolyte drops at low temperatures, which increases equivalent series resistance. While widely used for power-supply conditioning, poor high-frequency characteristics make them unsuitable for many applications. Electrolytic capacitors will self-degrade if unused for a period (around a year), and when full power is applied may short circuit, permanently damaging the capacitor and usually blowing a fuse or causing failure of rectifier diodes (for instance, in older equipment, arcing in rectifier tubes). They can be restored before use (and damage) by gradually applying the operating voltage, often done on antique vacuum tube equipment over a period of 30 minutes by using a variable transformer to supply AC power. Unfortunately, the use of this technique may be less satisfactory for some solid state equipment, which may be damaged by operation below its normal power range, requiring that the power supply first be isolated from the consuming circuits. Such remedies may not be applicable to modern high-frequency power supplies as these produce full output voltage even with reduced input.

Question: What is one type of metal which the conducting plates in electrolytic capacitors are commonly made of?


Answer: an oxide dielectric layer

Question: What type of dielectric layer is used in electrolytic capacitors?


Answer: drops at low temperatures

Question: What happens to the conductivity of the electrolyte at low temperatures?


Answer: by gradually applying the operating voltage

Question: How can electrolytic capacitors be safely used after having been stored unused for a long time?


Answer: these produce full output voltage even with reduced input

Question: Why might the method gradually applying the operating voltage not be suitable to protect electrolytic capacitors in modern devices?


Answer: Supercapacitors store large amounts of energy

Context: Several other types of capacitor are available for specialist applications. Supercapacitors store large amounts of energy. Supercapacitors made from carbon aerogel, carbon nanotubes, or highly porous electrode materials, offer extremely high capacitance (up to 5 kF as of 2010[update]) and can be used in some applications instead of rechargeable batteries. Alternating current capacitors are specifically designed to work on line (mains) voltage AC power circuits. They are commonly used in electric motor circuits and are often designed to handle large currents, so they tend to be physically large. They are usually ruggedly packaged, often in metal cases that can be easily grounded/earthed. They also are designed with direct current breakdown voltages of at least five times the maximum AC voltage.

Question: What is the main feature of a supercapacitor?


Answer: carbon nanotubes

Question: What is one type of material with which a supercapacitor may be constructed?


Answer: up to 5 kF

Question: As of 2010, what is the highest capacitance a supercapacitor has achieved?


Answer: Alternating current capacitors

Question: What type of capacitor is commonly used in electric motor circuits?


Answer: at least five times the maximum AC voltage

Question: How many times the maximum AC voltage are AC capacitors designed to withstand?


Answer: driven with a time-varying voltage that changes rapidly

Context: If a capacitor is driven with a time-varying voltage that changes rapidly enough, at some frequency the polarization of the dielectric cannot follow the voltage. As an example of the origin of this mechanism, the internal microscopic dipoles contributing to the dielectric constant cannot move instantly, and so as frequency of an applied alternating voltage increases, the dipole response is limited and the dielectric constant diminishes. A changing dielectric constant with frequency is referred to as dielectric dispersion, and is governed by dielectric relaxation processes, such as Debye relaxation. Under transient conditions, the displacement field can be expressed as (see electric susceptibility):

Question: Under what condition might the polarization of the dielectric be unable to follow the voltage?


Answer: the internal microscopic dipoles

Question: What type of dipoles which add to the dielectric constant cannot move instantly if a rapidly changing time varying voltage is driving the capacitor?


Answer: dielectric dispersion

Question: What is it called when a dielectric constant changes with frequency?


Answer: dielectric relaxation processes

Question: What regulates dielectric dispersion?


Answer: Debye relaxation

Question: What is an example of a dielectric relaxation process?


Answer: Z(ω)

Context: where a single prime denotes the real part and a double prime the imaginary part, Z(ω) is the complex impedance with the dielectric present, Ccmplx(ω) is the so-called complex capacitance with the dielectric present, and C0 is the capacitance without the dielectric. (Measurement "without the dielectric" in principle means measurement in free space, an unattainable goal inasmuch as even the quantum vacuum is predicted to exhibit nonideal behavior, such as dichroism. For practical purposes, when measurement errors are taken into account, often a measurement in terrestrial vacuum, or simply a calculation of C0, is sufficiently accurate.)

Question: How is the complex impedance with dielectric represented mathematically?


Answer: C0

Question: How is the complex capacitance without dielectric represented mathematically?


Answer: even the quantum vacuum is predicted to exhibit nonideal behavior

Question: Why is the value of C0 unattainable in reality?


Answer: in terrestrial vacuum

Question: Under what condition is the approximation C0 sufficiently accurate for calculation purposes?


Answer: Ccmplx(ω)

Question: How is the complex capacitance mathematically represented with the dielectric present?


Answer: microfarads and less

Context: The arrangement of plates and dielectric has many variations depending on the desired ratings of the capacitor. For small values of capacitance (microfarads and less), ceramic disks use metallic coatings, with wire leads bonded to the coating. Larger values can be made by multiple stacks of plates and disks. Larger value capacitors usually use a metal foil or metal film layer deposited on the surface of a dielectric film to make the plates, and a dielectric film of impregnated paper or plastic – these are rolled up to save space. To reduce the series resistance and inductance for long plates, the plates and dielectric are staggered so that connection is made at the common edge of the rolled-up plates, not at the ends of the foil or metalized film strips that comprise the plates.

Question: What order of magnitude of capacitance is suitable for capacitors comprised of ceramic disks with metallic coatings?


Answer: multiple stacks of plates and disks

Question: How are larger value capacitors often constructed?


Answer: impregnated paper or plastic – these are rolled up to save space

Question: What do larger value capacitors often use as the dielectric medium?


Answer: To reduce the series resistance and inductance

Question: Why are the plates and dielectrics often staggered in larger value capacitors?


Answer: metal film layer deposited on the surface of a dielectric film

Question: How are the conductive plates often made for larger value capacitors?


Answer: axially

Context: Capacitors may have their connecting leads arranged in many configurations, for example axially or radially. "Axial" means that the leads are on a common axis, typically the axis of the capacitor's cylindrical body – the leads extend from opposite ends. Radial leads might more accurately be referred to as tandem; they are rarely actually aligned along radii of the body's circle, so the term is inexact, although universal. The leads (until bent) are usually in planes parallel to that of the flat body of the capacitor, and extend in the same direction; they are often parallel as manufactured.

Question: What is one type of configuration in which a capacitor may have its connecting leads organized?


Answer: radially

Question: What is another type of configuration in which a capacitor may have its connecting leads arranged?


Answer: Radial

Question: Which type of configuration is often manufactured with the leads parallel to the body of the capacitor?


Answer: on a common axis

Question: How are the leads of an axially configured capacitor arranged?


Answer: as tandem

Question: How could radial leads be more correctly described?


Answer: the 1930s

Context: Small, cheap discoidal ceramic capacitors have existed since the 1930s, and remain in widespread use. Since the 1980s, surface mount packages for capacitors have been widely used. These packages are extremely small and lack connecting leads, allowing them to be soldered directly onto the surface of printed circuit boards. Surface mount components avoid undesirable high-frequency effects due to the leads and simplify automated assembly, although manual handling is made difficult due to their small size.

Question: Since when have inexpensive ceramic disc capacitors existed?


Answer: the 1980s

Question: Since when have surface mount packages for capacitors been commonly in use?


Answer: connecting leads

Question: What do surface mount packages lack that allows their use on the surface of printed circuit boards?


Answer: simplify automated assembly

Question: What is one benefit of using surface mount components?


Answer: manual handling is made difficult due to their small size

Question: What is one difficulty when using surface mount components?


Answer: the plate spacing

Context: Mechanically controlled variable capacitors allow the plate spacing to be adjusted, for example by rotating or sliding a set of movable plates into alignment with a set of stationary plates. Low cost variable capacitors squeeze together alternating layers of aluminum and plastic with a screw. Electrical control of capacitance is achievable with varactors (or varicaps), which are reverse-biased semiconductor diodes whose depletion region width varies with applied voltage. They are used in phase-locked loops, amongst other applications.

Question: What do mechanically controlled variable capacitors enable to be modified?


Answer: with a screw

Question: How do cheap variable capacitors vary the separation distance between layers of a plastic and aluminum?


Answer: reverse-biased semiconductor diodes

Question: Of what type of diodes are varactors or varicaps comprised?


Answer: depletion region

Question: What varies as a function of voltage in varactors?


Answer: phase-locked loops

Question: What is an application of varactors?


Answer: display the actual capacitance together with the unit (for example, 220 μF)

Context: Most capacitors have numbers printed on their bodies to indicate their electrical characteristics. Larger capacitors like electrolytics usually display the actual capacitance together with the unit (for example, 220 μF). Smaller capacitors like ceramics, however, use a shorthand consisting of three numeric digits and a letter, where the digits indicate the capacitance in pF (calculated as XY × 10Z for digits XYZ) and the letter indicates the tolerance (J, K or M for ±5%, ±10% and ±20% respectively).

Question: How do larger capacitors present their electrical characteristics?


Answer: three numeric digits and a letter

Question: What does the abbreviated electrical characteristics of smaller capacitors consist of?


Answer: the digits indicate the capacitance

Question: What part of the electrical characteristics of smaller capacitors do the digits of the abbreviated notation represent ?


Answer: the letter indicates the tolerance

Question: What does the letter of the abbreviated notation for the electrical characteristics of smaller capacitors represent?


Answer: in pF

Question: In what SI unit is the capacitance reported on smaller capacitors?


Answer: to provide a "clean" power supply for signal or control circuits

Context: Capacitors are connected in parallel with the power circuits of most electronic devices and larger systems (such as factories) to shunt away and conceal current fluctuations from the primary power source to provide a "clean" power supply for signal or control circuits. Audio equipment, for example, uses several capacitors in this way, to shunt away power line hum before it gets into the signal circuitry. The capacitors act as a local reserve for the DC power source, and bypass AC currents from the power supply. This is used in car audio applications, when a stiffening capacitor compensates for the inductance and resistance of the leads to the lead-acid car battery.

Question: Why are capacitors connected in parallel with the power circuits of many devices and large systems?


Answer: as a local reserve for the DC power source

Question: How do the capacitors connected in parallel act with currents from the power supply?


Answer: the inductance

Question: What is one value a stiffening capacitor accounts for when used in for car audio purposes?


Answer: resistance

Question: What is another value a stiffening capacitor accounts for when used in for car audio purposes?


Answer: conceal current fluctuations

Question: What do parallel capacitors do to fluctuating current in order to deliver "clean" power for control circuits?


Answer: In electric power distribution

Context: In electric power distribution, capacitors are used for power factor correction. Such capacitors often come as three capacitors connected as a three phase load. Usually, the values of these capacitors are given not in farads but rather as a reactive power in volt-amperes reactive (var). The purpose is to counteract inductive loading from devices like electric motors and transmission lines to make the load appear to be mostly resistive. Individual motor or lamp loads may have capacitors for power factor correction, or larger sets of capacitors (usually with automatic switching devices) may be installed at a load center within a building or in a large utility substation.

Question: In what scenario are capacitors used for power factor correction?


Answer: as three capacitors connected as a three phase load

Question: How are capacitors used for for power factor correction prepared?


Answer: reactive power in volt-amperes reactive (var)

Question: In what what unit is the capacitance reported for capacitors used in power factor correction?


Answer: to counteract inductive loading

Question: What is the reason for using capacitors in power factor correction?


Answer: at a load center within a building

Question: How are power factor correction capacitors sometimes installed?


Answer: the current through the inductance collapses quickly

Context: When an inductive circuit is opened, the current through the inductance collapses quickly, creating a large voltage across the open circuit of the switch or relay. If the inductance is large enough, the energy will generate a spark, causing the contact points to oxidize, deteriorate, or sometimes weld together, or destroying a solid-state switch. A snubber capacitor across the newly opened circuit creates a path for this impulse to bypass the contact points, thereby preserving their life; these were commonly found in contact breaker ignition systems, for instance. Similarly, in smaller scale circuits, the spark may not be enough to damage the switch but will still radiate undesirable radio frequency interference (RFI), which a filter capacitor absorbs. Snubber capacitors are usually employed with a low-value resistor in series, to dissipate energy and minimize RFI. Such resistor-capacitor combinations are available in a single package.

Question: What happens to the current when an inductive circuit is opened?


Answer: a large voltage across the open circuit of the switch

Question: What happens to the voltage when an inductive circuit is opened?


Answer: A snubber capacitor

Question: What type of capacitor is used to make a path to bypass the contact points?


Answer: contact breaker ignition systems

Question: What is a typical system in which a snubber capacitor is found?


Answer: a filter capacitor

Question: What type of capacitor absorbs radio frequency interference?


Answer: a rotational motion on the rotor

Context: In single phase squirrel cage motors, the primary winding within the motor housing is not capable of starting a rotational motion on the rotor, but is capable of sustaining one. To start the motor, a secondary "start" winding has a series non-polarized starting capacitor to introduce a lead in the sinusoidal current. When the secondary (start) winding is placed at an angle with respect to the primary (run) winding, a rotating electric field is created. The force of the rotational field is not constant, but is sufficient to start the rotor spinning. When the rotor comes close to operating speed, a centrifugal switch (or current-sensitive relay in series with the main winding) disconnects the capacitor. The start capacitor is typically mounted to the side of the motor housing. These are called capacitor-start motors, that have relatively high starting torque. Typically they can have up-to four times as much starting torque than a split-phase motor and are used on applications such as compressors, pressure washers and any small device requiring high starting torques.

Question: What is the main winding on a squirrel cage motor capable of withstanding?


Answer: series non-polarized starting capacitor

Question: What sort of capacitors are used on the second winding of a squirrel cage motor?


Answer: introduce a lead in the sinusoidal current

Question: What does the capacitor on the second winding of a squirrel cage motor do?


Answer: disconnects the capacitor

Question: What does the centrifugal switch do the capacitor when the rotor achieves operating speed?


Answer: to the side of the motor housing

Question: Where is the start capacitor commonly mounted?


Answer: over 15 joules of energy

Context: Capacitors may retain a charge long after power is removed from a circuit; this charge can cause dangerous or even potentially fatal shocks or damage connected equipment. For example, even a seemingly innocuous device such as a disposable-camera flash unit, powered by a 1.5 volt AA battery, has a capacitor which may contain over 15 joules of energy and be charged to over 300 volts. This is easily capable of delivering a shock. Service procedures for electronic devices usually include instructions to discharge large or high-voltage capacitors, for instance using a Brinkley stick. Capacitors may also have built-in discharge resistors to dissipate stored energy to a safe level within a few seconds after power is removed. High-voltage capacitors are stored with the terminals shorted, as protection from potentially dangerous voltages due to dielectric absorption or from transient voltages the capacitor may pick up from static charges or passing weather events.

Question: How much energy could a capacitor in a disposable camera contain?


Answer: over 300 volts

Question: To what voltage could a capacitor from a disposable camera be charged to?


Answer: a Brinkley stick

Question: What device can be used to discharge large voltage capacitors?


Answer: with the terminals shorted

Question: How are the terminals of high voltage capacitors stored?


Answer: from static charges

Question: What type of charge could a capacitor pick up a transient charge from?


Answer: when subjected to voltages or currents beyond their rating

Context: Capacitors may catastrophically fail when subjected to voltages or currents beyond their rating, or as they reach their normal end of life. Dielectric or metal interconnection failures may create arcing that vaporizes the dielectric fluid, resulting in case bulging, rupture, or even an explosion. Capacitors used in RF or sustained high-current applications can overheat, especially in the center of the capacitor rolls. Capacitors used within high-energy capacitor banks can violently explode when a short in one capacitor causes sudden dumping of energy stored in the rest of the bank into the failing unit. High voltage vacuum capacitors can generate soft X-rays even during normal operation. Proper containment, fusing, and preventive maintenance can help to minimize these hazards.

Question: What could cause the failure of a capacitor?


Answer: overheat

Question: What can happen to capacitors used in high current applications?


Answer: violently explode

Question: What can happen to capacitors used in high energy capacitor banks?


Answer: High voltage vacuum capacitors

Question: What type of capacitors can generate soft x-rays?


Answer: preventive maintenance

Question: What is one way to help minimize capacitor dangers?


Answer: The history of science

Context: The history of science is the study of the development of science and scientific knowledge, including both the natural sciences and social sciences. (The history of the arts and humanities is termed as the history of scholarship.) Science is a body of empirical, theoretical, and practical knowledge about the natural world, produced by scientists who emphasize the observation, explanation, and prediction of real world phenomena. Historiography of science, in contrast, often draws on the historical methods of both intellectual history and social history.

Question: What are natural and social sciences a subcategory of?


Answer: the history of scholarship

Question: What is the history of arts and humanities called?


Answer: real world

Question: What kind of phenomena does science study?


Answer: Historiography of science

Question: Intellectual history and social history are used in what?


Answer: William Whewell

Context: The English word scientist is relatively recent—first coined by William Whewell in the 19th century. Previously, people investigating nature called themselves natural philosophers. While empirical investigations of the natural world have been described since classical antiquity (for example, by Thales, Aristotle, and others), and scientific methods have been employed since the Middle Ages (for example, by Ibn al-Haytham, and Roger Bacon), the dawn of modern science is often traced back to the early modern period and in particular to the scientific revolution that took place in 16th- and 17th-century Europe. Scientific methods are considered to be so fundamental to modern science that some consider earlier inquiries into nature to be pre-scientific. Traditionally, historians of science have defined science sufficiently broadly to include those inquiries.

Question: Who coined the word "scientist"?


Answer: 19th century

Question: When was the word "scientist" created?


Answer: natural philosophers

Question: What are people who study nature called?


Answer: the Middle Ages

Question: Ibn al-Haytham and Roger Bacon were scientists in which time period?


Answer: the scientific revolution

Question: When was the beginning of modern science considered to be?


Answer: true theories

Context: From the 18th century through late 20th century, the history of science, especially of the physical and biological sciences, was often presented in a progressive narrative in which true theories replaced false beliefs. More recent historical interpretations, such as those of Thomas Kuhn, tend to portray the history of science in different terms, such as that of competing paradigms or conceptual systems in a wider matrix that includes intellectual, cultural, economic and political themes outside of science.

Question: What replaced false beliefs?


Answer: Thomas Kuhn

Question: Who depicts the history of science in a wider matrix?


Answer: the 18th century

Question: What time period did the history of science begin to take a progressive narrative?


Answer: competing paradigms

Question: Thomas Kuhn used conceptual systems and what other term to define the history of science?


Answer: a surplus of food

Context: The development of writing enabled knowledge to be stored and communicated across generations with much greater fidelity. Combined with the development of agriculture, which allowed for a surplus of food, it became possible for early civilizations to develop, because more time and effort could be devoted to tasks (other than food production) than hunter-gatherers or early subsistence farmers had available. This surplus allowed a community to support individuals who did things other than work towards bare survival. These other tasks included systematic studies of nature, study of written information gathered and recorded by others, and often of adding to that body of information.

Question: The advancement of agriculture made what possible?


Answer: food production

Question: Having a surplus of food allowed farmers and hunter-gatherers to spend less time working on what?


Answer: work towards bare survival

Question: Before agriculture advancements, what were farmers having to do?


Answer: The development of writing

Question: What advancement aided in spreading knowledge across generations?


Answer: community

Question: Who was able to support the people who were adding to the written knowledge of nature?


Answer: Ancient Egypt

Context: Ancient Egypt made significant advances in astronomy, mathematics and medicine. Their development of geometry was a necessary outgrowth of surveying to preserve the layout and ownership of farmland, which was flooded annually by the Nile river. The 3-4-5 right triangle and other rules of thumb were used to build rectilinear structures, and the post and lintel architecture of Egypt. Egypt was also a center of alchemy research for much of the Mediterranean.The Edwin Smith papyrus is one of the first medical documents still extant, and perhaps the earliest document that attempts to describe and analyse the brain: it might be seen as the very beginnings of modern neuroscience. However, while Egyptian medicine had some effective practices, it was not without its ineffective and sometimes harmful practices. Medical historians believe that ancient Egyptian pharmacology, for example, was largely ineffective. Nevertheless, it applies the following components to the treatment of disease: examination, diagnosis, treatment, and prognosis, which display strong parallels to the basic empirical method of science and according to G. E. R. Lloyd played a significant role in the development of this methodology. The Ebers papyrus (c. 1550 BC) also contains evidence of traditional empiricism.

Question: Which civilization advanced in astronomy, mathematics, and medicine?


Answer: geometry

Question: What did Egyptians use to better organize their farmland?


Answer: The 3-4-5 right triangle

Question: What theory did the Egyptians use to build rectilinear structures?


Answer: alchemy

Question: What research was Egypt known for?


Answer: The Edwin Smith papyrus

Question: What is the name of the earliest medical document?


Answer: Sumer

Context: From their beginnings in Sumer (now Iraq) around 3500 BC, the Mesopotamian people began to attempt to record some observations of the world with numerical data. But their observations and measurements were seemingly taken for purposes other than for elucidating scientific laws. A concrete instance of Pythagoras' law was recorded, as early as the 18th century BC: the Mesopotamian cuneiform tablet Plimpton 322 records a number of Pythagorean triplets (3,4,5) (5,12,13). ..., dated 1900 BC, possibly millennia before Pythagoras, but an abstract formulation of the Pythagorean theorem was not.

Question: Where did the Mesopotamian people originate from?


Answer: 3500 BC

Question: How far back do the Mesopotamian people go?


Answer: numerical data

Question: What did the Mesopotamian use to record data about the world around them?


Answer: 18th century BC

Question: What was the earliest recording of Pythagoras' law?


Answer: Plimpton 322

Question: Which tablet had Pythagorean triplets on it?


Answer: scribes

Context: In Babylonian astronomy, records of the motions of the stars, planets, and the moon are left on thousands of clay tablets created by scribes. Even today, astronomical periods identified by Mesopotamian proto-scientists are still widely used in Western calendars such as the solar year and the lunar month. Using these data they developed arithmetical methods to compute the changing length of daylight in the course of the year and to predict the appearances and disappearances of the Moon and planets and eclipses of the Sun and Moon. Only a few astronomers' names are known, such as that of Kidinnu, a Chaldean astronomer and mathematician. Kiddinu's value for the solar year is in use for today's calendars. Babylonian astronomy was "the first and highly successful attempt at giving a refined mathematical description of astronomical phenomena." According to the historian A. Aaboe, "all subsequent varieties of scientific astronomy, in the Hellenistic world, in India, in Islam, and in the West—if not indeed all subsequent endeavour in the exact sciences—depend upon Babylonian astronomy in decisive and fundamental ways."

Question: Who wrote on the clay tablets in Babylonian astronomy?


Answer: in Western calendars

Question: Where are Mesopotamian astronomical periods still used?


Answer: a Chaldean astronomer and mathematician

Question: Who was Kidinnu?


Answer: A. Aaboe

Question: Who believes that the Hellenistic world relies on Babylonian astronomy?


Answer: today's calendars

Question: Where can Kidinnu's solar year be found in use?