How many years as Czech continued to evolve and gain in regional importance?

Czech continued to evolve and gain in regional importance for hundreds of years, and has been a literary language in the Slovak lands since the early fifteenth century. A biblical translation, the Kralice Bible, was published during the late sixteenth century (around the time of the King James and Luther versions) which was more linguistically conservative than either. The publication of the Kralice Bible spawned widespread nationalism, and in 1615 the government of Bohemia ruled that only Czech-speaking residents would be allowed to become full citizens or inherit goods or land. This, and the conversion of the Czech upper classes from the Habsburg Empire's Catholicism to Protestantism, angered the Habsburgs and helped trigger the Thirty Years' War (where the Czechs were defeated at the Battle of White Mountain). The Czechs became serfs; Bohemia's printing industry (and its linguistic and political rights) were dismembered, removing official regulation and support from its language. German quickly became the dominant language in Bohemia.


What did the publication of the Kralice Bible spawn?


In what war were the Czechs defeated at the Battle of White Mountain?


What language became dominant in Bohemia after the Czech's defeat?


When do linguists agree modern Czech originated?

The consensus among linguists is that modern, standard Czech originated during the eighteenth century. By then the language had developed a literary tradition, and since then it has changed little; journals from that period have no substantial differences from modern standard Czech, and contemporary Czechs can understand them with little difficulty. Changes include the morphological shift of í to ej and é to í (although é survives for some uses) and the merging of í and the former ejí. Sometime before the eighteenth century, the Czech language abandoned a distinction between phonemic /l/ and /ʎ/ which survives in Slovak.


What had Czech developed by the 18th century?


Journals from the 18th century have no substantial differences from what?


How much difficulty do contemporary Czechs have in understanding material from the 18th century?


What did the Czech language abandon which survives in Slovak?


What did the Czechs as a people gain during the mid-18th century?

The Czech people gained widespread national pride during the mid-eighteenth century, inspired by the Age of Enlightenment a half-century earlier. Czech historians began to emphasize their people's accomplishments from the fifteenth through the seventeenth centuries, rebelling against the Counter-Reformation (which had denigrated Czech and other non-Latin languages). Czech philologists studied sixteenth-century texts, advocating the return of the language to high culture. This period is known as the Czech National Revival (or Renascence).


What inspired the Czech's national pride?


What did Czech historians emphasize about their countrymen?


What is the period during the mid-eighteenth century also remembered as?


What was the professions of Joseph Dobrovský?

During the revival, in 1809 linguist and historian Josef Dobrovský released a German-language grammar of Old Czech entitled Ausführliches Lehrgebäude der böhmischen Sprache (Comprehensive Doctrine of the Bohemian Language). Dobrovský had intended his book to be descriptive, and did not think Czech had a realistic chance of returning as a major language. However, Josef Jungmann and other revivalists used Dobrovský's book to advocate for a Czech linguistic revival. Changes during this time included spelling reform (notably, í in place of the former j and j in place of g), the use of t (rather than ti) to end infinitive verbs and the non-capitalization of nouns (which had been a late borrowing from German). These changes differentiated Czech from Slovak. Modern scholars disagree about whether the conservative revivalists were motivated by nationalism or considered contemporary spoken Czech unsuitable for formal, widespread use.


What didn't Dobrovský think Czech had a chance of returning as?


What year did Joseph Dobrovský release a German-language grammar of Old Czech?


Who disagree about whether the revivalists were motivated by nationalism or if they considered contemporary spoken Czech unsuitable for formal use?


What is the official language of the Czech republic?

Czech, the official language of the Czech Republic (a member of the European Union since 2004), is one of the EU's official languages and the 2012 Eurobarometer survey found that Czech was the foreign language most often used in Slovakia. Economist Jonathan van Parys collected data on language knowledge in Europe for the 2012 European Day of Languages. The five countries with the greatest use of Czech were the Czech Republic (98.77 percent), Slovakia (24.86 percent), Portugal (1.93 percent), Poland (0.98 percent) and Germany (0.47 percent).


How long has the Czech Republic been a member of the European Union?


What distinction does Czech have in Slovakia?


Who collected data on language knowledge in Europe for the 2012 European Day of Languages?


Of the five countries with the greatest use of Czech, which country had the lowest percent of use?


Czechs immigrated from Europe to the U.S. primary from 1848 to when?

Immigration of Czechs from Europe to the United States occurred primarily from 1848 to 1914. Czech is a Less Commonly Taught Language in U.S. schools, and is taught at Czech heritage centers. Large communities of Czech Americans live in the states of Texas, Nebraska and Wisconsin. In the 2000 United States Census, Czech was reported as the most-common language spoken at home (besides English) in Valley, Butler and Saunders Counties, Nebraska and Republic County, Kansas. With the exception of Spanish (the non-English language most commonly spoken at home nationwide), Czech was the most-common home language in over a dozen additional counties in Nebraska, Kansas, Texas, North Dakota and Minnesota. As of 2009, 70,500 Americans spoke Czech as their first language (49th place nationwide, behind Turkish and ahead of Swedish).


What kind of language is Czech in U.S. schools?


What states have large communities of Czech Americans?


What is the most commonly spoken non-English language at homes nationwide in the U.S.?


How many Americans spoke Czech as their first language as of 2009?


How many regional dialects does Czech have?

In addition to a spoken standard and a closely related written standard, Czech has several regional dialects primarily used in rural areas by speakers less proficient in other dialects or standard Czech. During the second half of the twentieth century, Czech dialect use began to weaken. By the early 1990s dialect use was stigmatized, associated with the shrinking lower class and used in literature or other media for comedic effect. Increased travel and media availability to dialect-speaking populations has encouraged them to shift to (or add to their own dialect) standard Czech. Although Czech has received considerable scholarly interest for a Slavic language, this interest has focused primarily on modern standard Czech and ancient texts rather than dialects. Standard Czech is still the norm for politicians, businesspeople and other Czechs in formal situations, but Common Czech is gaining ground in journalism and the mass media.


Where are dialects of Czech commonly found?


What is dialect use associated with and thus stigmatized because of?


What kind of scholarly interest has Czech received?


What Czech dialect is gaining ground in journalism and the mass media?


What are the dialects spoken in Moravia and Silesia known as?

The Czech dialects spoken in Moravia and Silesia are known as Moravian (moravština). In the Austro-Hungarian Empire, "Bohemian-Moravian-Slovak" was a language citizens could register as speaking (with German, Polish and several others). Of the Czech dialects, only Moravian is distinguished in nationwide surveys by the Czech Statistical Office. As of 2011, 62,908 Czech citizens spoke Moravian as their first language and 45,561 were diglossal (speaking Moravian and standard Czech as first languages).


Where could citizens register "Bohemian-Moravian-Slovak' as being their spoken language?


Which of the Czech dialects is the only one distinguished in the nationwide surveys by the Czech Statistical Office?


How many Czechs spoke Moravian as their first language as of 2011?


How many Czechs spoke both Moravian and standard Czech as first languages in 2011?


How many basic vowel phonemes does Czech contain?

Czech contains ten basic vowel phonemes, and three more found only in loanwords. They are /a/, /ɛ/, /ɪ/, /o/, and /u/, their long counterparts /aː/, /ɛː/, /iː/, /oː/ and /uː/, and three diphthongs, /ou̯/, /au̯/ and /ɛu̯/. The latter two diphthongs and the long /oː/ are exclusive to loanwords. Vowels are never reduced to schwa sounds when unstressed. Each word usually has primary stress on its first syllable, except for enclitics (minor, monosyllabic, unstressed syllables). In all words of more than two syllables, every odd-numbered syllable receives secondary stress. Stress is unrelated to vowel length, and the possibility of stressed short vowels and unstressed long vowels can be confusing to students whose native language combines the features (such as English).


Where are three additional vowel phonemes found in Czech?


What are vowel sounds never reduced to when unstressed?


What a few exceptions where is the primary word stress in Czech?


In Czech, what are loanwords from other languages associated with?

Although older German loanwords were colloquial, recent borrowings from other languages are associated with high culture. During the nineteenth century, words with Greek and Latin roots were rejected in favor of those based on older Czech words and common Slavic roots; "music" is muzyka in Polish and музыка (muzyka) in Russian, but in Czech it is hudba. Some Czech words have been borrowed as loanwords into English and other languages—for example, robot (from robota, "labor") and polka (from polka, "Polish woman" or from "půlka" "half").


What word roots in the 19th century were rejected in favor of words with more common Slavic roots?


How does one say the word "music" in Czech?


What Czech word did the English "robot" derive from?


What is the meaning of the Czech word "robota"?


Czech's word order is flexible because it uses what to convey word function in a sentence?

Because Czech uses grammatical case to convey word function in a sentence (instead of relying on word order, as English does), its word order is flexible. As a pro-drop language, in Czech an intransitive sentence can consist of only a verb; information about its subject is encoded in the verb. Enclitics (primarily auxiliary verbs and pronouns) must appear in the second syntactic slot of a sentence, after the first stressed unit. The first slot must contain a subject and object, a main form of a verb, an adverb or a conjunction (except for the light conjunctions a, "and", i, "and even" or ale, "but").


In Czech an intransitive sentence may consist of only what?


What is encoded about a subject in verbs in Czech?


What is a hard to pronounce and remember term meaning primarily auxiliary verbs and pronouns?


Where must enclitics appear in a sentence?


What is the sentence structure of Czech syntax?

Czech syntax has a subject–verb–object sentence structure. In practice, however, word order is flexible and used for topicalization and focus. Although Czech has a periphrastic passive construction (like English), colloquial word-order changes frequently produce the passive voice. For example, to change "Peter killed Paul" to "Paul was killed by Peter" the order of subject and object is inverted: Petr zabil Pavla ("Peter killed Paul") becomes "Paul, Peter killed" (Pavla zabil Petr). Pavla is in the accusative case, the grammatical object (in this case, the victim) of the verb.


Because word order is flexible in Czech, what does it tend to actually be used for?


What kind of passive construction does Czech have?


What happens to the subject and object to produce a passive voice in Czech?


What case is the grammatical object of a verb?


How many grammatical cases can nouns and adjectives be declined into in Czech?

In Czech, nouns and adjectives are declined into one of seven grammatical cases. Nouns are inflected to indicate their use in a sentence. A nominative–accusative language, Czech marks subject nouns with nominative case and object nouns with accusative case. The genitive case marks possessive nouns and some types of movement. The remaining cases (instrumental, locative, vocative and dative) indicate semantic relationships, such as secondary objects, movement or position (dative case) and accompaniment (instrumental case). An adjective's case agrees with that of the noun it describes. When Czech children learn their language's declension patterns, the cases are referred to by number:


What nouns does Czech use the accusative case to mark?


What must an adjective's case agree with in Czech?


How many genders does Czech distinguish?

Czech distinguishes three genders—masculine, feminine, and neuter—and the masculine gender is subdivided into animate and inanimate. With few exceptions, feminine nouns in the nominative case end in -a, -e, or -ost; neuter nouns in -o, -e, or -í, and masculine nouns in a consonant. Adjectives agree in gender and animacy (for masculine nouns in the accusative or genitive singular and the nominative plural) with the nouns they modify. The main effect of gender in Czech is the difference in noun and adjective declension, but other effects include past-tense verb endings: for example, dělal (he did, or made); dělala (she did, or made) and dělalo (it did, or made).


What categories is the masculine gender in Czech divided into?


What do Czech adjectives agree with in the nouns they modify?


What is the main effect of gender in Czech?


Nouns are also inflected for number, distinguishing between singular and plural. Typical of a Slavic language, Czech cardinal numbers one through four allow the nouns and adjectives they modify to take any case, but numbers over five place these nouns and adjectives in the genitive case when the entire expression is in nominative or accusative case. The Czech koruna is an example of this feature; it is shown here as the subject of a hypothetical sentence, and declined as genitive for numbers five and up.


What are the cardinal numbers one through four in Czech allowed to take?


What is Czech's handling of cardinal numbers typical of?


What do Slavic languages tend to do to their verbs?

Typical of Slavic languages, Czech marks its verbs for one of two grammatical aspects: perfective and imperfective. Most verbs are part of inflected aspect pairs—for example, koupit (perfective) and kupovat (imperfective). Although the verbs' meaning is similar, in perfective verbs the action is completed and in imperfective verbs it is ongoing. This is distinct from past and present tense, and any Czech verb of either aspect can be conjugated into any of its three tenses. Aspect describes the state of the action at the time specified by the tense.


What describes the state of the action of the verb at the time specified by its tense?


What two grammatical aspects can verbs in Czech have?


In perfective verbs, what state is the action the verb describes in?


In which verbs in Czech is the action the verb describes still ongoing?


How many ways can a verb in an aspect pair differ?

The verbs of most aspect pairs differ in one of two ways: by prefix or by suffix. In prefix pairs, the perfective verb has an added prefix—for example, the imperfective psát (to write, to be writing) compared with the perfective napsat (to write down, to finish writing). The most common prefixes are na-, o-, po-, s-, u-, vy-, z- and za-. In suffix pairs, a different infinitive ending is added to the perfective stem; for example, the perfective verbs koupit (to buy) and prodat (to sell) have the imperfective forms kupovat and prodávat. Imperfective verbs may undergo further morphology to make other imperfective verbs (iterative and frequentative forms), denoting repeated or regular action. The verb jít (to go) has the iterative form chodit (to go repeatedly) and the frequentative form chodívat (to go regularly).


What does a perfective verb have added in prefix pairs?


What is added to the ending in suffix pairs?


What can imperfective verb undergo to make other imperfective verbs?


What type of action can second level morphed imperfective verbs denote?


What verb form is found in Czech dictionaries?

The infinitive form ends in t (archaically, ti). It is the form found in dictionaries and the form that follows auxiliary verbs (for example, můžu tě slyšet—"I can hear you"). Czech verbs have three grammatical moods: indicative, imperative and conditional. The imperative mood adds specific endings for each of three person (or number) categories: -Ø/-i/-ej for second-person singular, -te/-ete/-ejte for second-person plural and -me/-eme/-ejme for first-person plural. The conditional mood is formed with a particle after the past-tense verb. This mood indicates possible events, expressed in English as "I would" or "I wish".


How many grammatical moods do Czech verbs have?


What are the grammatical moods of Czech verbs?


What mood adds specific endings for each of three person or number categories?


Which Czech verb mood indicates possible events?


What language has one of the most phonemic orthographies of all European languages?

Czech has one of the most phonemic orthographies of all European languages. Its thirty-one graphemes represent thirty sounds (in most dialects, i and y have the same sound), and it contains only one digraph: ch, which follows h in the alphabet. As a result, some of its characters have been used by phonologists to denote corresponding sounds in other languages. The characters q, w and x appear only in foreign words. The háček (ˇ) is used with certain letters to form new characters: š, ž, and č, as well as ň, ě, ř, ť, and ď (the latter five uncommon outside Czech). The last two letters are sometimes written with a comma above (ʼ, an abbreviated háček) because of their height. The character ó exists only in loanwords and onomatopoeia.


What have some of Czech's characters been used for by phonologists to denote?


What character in Czech only exists in loanwords?


In Czech, what type of words do the characters "q", "w" and "x" exclusively appear in?


What do Czech typographical features not associated with phonetics tend to resemble?

Czech typographical features not associated with phonetics generally resemble those of most Latin European languages, including English. Proper nouns, honorifics, and the first letters of quotations are capitalized, and punctuation is typical of other Latin European languages. Writing of ordinal numerals is similar to most European languages. The Czech language uses a decimal comma instead of a decimal point. When writing a long number, spaces between every three numbers (e.g. between hundreds and thousands) may be used for better orientation in handwritten texts, but not in decimal places, like in English. The number 1,234,567.8910 may be written as 1234567,8910 or 1 234 567,8910. Ordinal numbers (1st) use a point as in German (1.). In proper noun phrases (except personal names), only the first word is capitalized (Pražský hrad, Prague Castle).


In Czech, what is done to proper nouns, honorifics, and the first letters of quotations?


What is typical in Czech as other Latin European languages?


What language does Czech share its handling of ordinal format with?


What word is capitalized in proper noun phrases in Czech?


(デジモン Dejimon, branded as Digimon: Digital Monsters, stylized as DIGIMON), short for "Digital Monsters" (デジタルモンスター Dejitaru Monsutā), is a Japanese media franchise encompassing virtual pet toys, anime, manga, video games, films and a trading card game. The franchise focuses on Digimon creatures, which are monsters living in a "Digital World", a parallel universe that originated from Earth's various communication networks. In many incarnations, Digimon are raised by humans called "Digidestined" or "Tamers", and they team up to defeat evil Digimon and human villains who are trying to destroy the fabric of the Digital world.


What forms of entertainment does the Digimon franchise include?


What is the Digital World in which the Digimon creatures live?


What are the people who raise Digimon called?


What are the Digimon villians main goals?


The franchise was first created in 1997 as a series of virtual pets, akin to—and influenced in style by—the contemporary Tamagotchi or nano Giga Pet toys. The creatures were first designed to look cute and iconic even on the devices' small screens; later developments had them created with a harder-edged style influenced by American comics. The franchise gained momentum with its first anime incarnation, Digimon Adventure, and an early video game, Digimon World, both released in 1999. Several seasons of the anime and films based on them have aired, and the video game series has expanded into genres such as role-playing, racing, fighting, and MMORPGs. Other media forms have also been released.


Name the Digimon video game that was released in 1999.


Name two types of toys the original Digimon bore a close resemblence to.


What influenced the look of the Digimons?


In what year was the Digimon video game released?


What kind of toy were the original Digimon?

Digimon was first conceived as a virtual pet toy in the vein of Tamagotchis and, as such, took influence from Tamagotchis' cute and round designs. The small areas of the screens (16 by 16 pixels) meant that character designers had to create monsters whose forms would be easily recognizable. As such, many of the early Digimon—including Tyrannomon, the first one ever created—were based on dinosaurs. Many further designs were created by Kenji Watanabe, who was brought in to help with the "X-Antibody" creatures and art for the Digimon collectible card game. Watanabe was one influenced by American comics, which were beginning to gain popularity in Japan, and as such began to make his characters look stronger and "cool." The character creation process, however, has for most of the franchise's history been collaborative and reliant on conversation and brainstorming.


What kind of creatures where the early digimon patterned after?


What properties of american comics were the later generations of digimon trying to capture?


Who was the designer responsible for the westernization of Digimon character design?


What was the name of the original Digimon character?


What was the screen size of the Digimon toy?


What animals were the digimon based off of?


Who was the designer of the Digimon card game?


Digimon hatch from types of eggs which are called Digi-Eggs (デジタマ, Dejitama?). In the English iterations of the franchise there is another type of Digi-Egg that can be used to digivolve, or transform, Digimon. This second type of Digi-Egg is called a Digimental (デジメンタル, Dejimentaru?) in Japanese. (This type of Digi-Egg was also featured as a major object throughout season 2 as a way of Digivolution available only to certain characters at certain points throughout the season.) They age via a process called "Digivolution" which changes their appearance and increases their powers. The effect of Digivolution, however, is not permanent in the partner Digimon of the main characters in the anime, and Digimon who have digivolved will most of the time revert to their previous form after a battle or if they are too weak to continue. Some Digimon act feral. Most, however, are capable of intelligence and human speech. They are able to digivolve by the use of Digivices that their human partners have. In some cases, as in the first series, the DigiDestined (known as the 'Chosen Children' in the original Japanese) had to find some special items such as crests and tags so the Digimon could digivolve into further stages of evolution known as Ultimate and Mega in the dub.


What is the process of aging called for digimon?


What effect does digivolution have on digimon?


What were the eggs called that the Digimon were hatched from?


What is the second type of Digi-Eggs called?


What is the process called of how Digi-Eggs age?


What items were used to help the Digimon evolve?


Are there any circumstances under which a digimon cannot be reborn?

The first Digimon anime introduced the Digimon life cycle: They age in a similar fashion to real organisms, but do not die under normal circumstances because they are made of reconfigurable data, which can be seen throughout the show. Any Digimon that receives a fatal wound will dissolve into infinitesimal bits of data. The data then recomposes itself as a Digi-Egg, which will hatch when rubbed gently, and the Digimon goes through its life cycle again. Digimon who are reincarnated in this way will sometimes retain some or all their memories of their previous life. However, if a Digimon's data is completely destroyed, they will die.


What typically happens when digimon are killed?


When was the digimon life cycle first described?


What was introduced during the first Digimon anime?


What happened to a digimon that receives a fatal wound?


What happens to a digimon after it dissolves?


What happens if a Digimons data is completely destroyed?


What companies were responsible for the creation and subsequent release of the original digimon?

Digimon started out as digital pets called "Digital Monsters", similar in style and concept to the Tamagotchi. It was planned by WiZ and released by Bandai on June 26, 1997. The toy began as the simple concept of a Tamagotchi mainly for boys. The V-Pet is similar to its predecessors, with the exceptions of being more difficult and being able to fight other Digimon v-pets. Every owner would start with a Baby Digimon, train it, evolve it, take care of it, and then have battles with other Digimon owners to see who was stronger. The Digimon pet had several evolution capabilities and abilities too, so many owners had different Digimon. In December, the second generation of Digital Monster was released, followed by a third edition in 1998.


What made digimon different from similar digital pets?


What year was the second generation of digimon released?


Who was the main market for the original digimon?


What was involved in the original digimon virtual pet gameplay?


What did the Digimon pets originally start out as?


In what month was the second generation of the Digital Monsters Released?


What year was the third edition released?


What is the world in which the digimon live?

"Digimon" are "Digital Monsters". According to the stories, they are inhabitants of the "DigiWorld", a manifestation of Earth's communication network. The stories tell of a group of mostly pre-teens, who accompany special Digimon born to defend their world (and ours) from various evil forces. To help them surmount the most difficult obstacles found within both realms, the Digimon have the ability to evolve (Digivolve) In this process, the Digimon change appearance and become much stronger, often changing in personality as well. The group of children who come in contact with the Digital World changes from series to series.


What happens to a digimon after they evolve?


Who accompanies the digimon as they work to save their world?


Are the children who accompany the digimon always the same?


What is the world of the digimon called?


What group of kids are in charge of the Digimons?


What is the process called when Digimon get stronger?


As of 2011, there have been six series — Digimon Adventure, the follow-up sequel Digimon Adventure 02, Digimon Tamers, Digimon Frontier, Digimon Data Squad and Digimon Fusion. The first two series take place in the same fictional universe, but the third, fourth, fifth and sixth each occupy their own unique world. Each series is commonly based on the original storyline but things are added to make them unique. However, in Tamers, the Adventure universe is referred to as a commercial enterprise — a trading card game in Japan, plus a show-within-a-show in the English dub. It also features an appearance by a character from the Adventure universe. In addition, each series has spawned assorted feature films. Digimon still shows popularity, as new card series, video games, and movies are still being produced and released: new card series include Eternal Courage, Hybrid Warriors, Generations, and Operation X; the video game, Digimon Rumble Arena 2; and the previously unreleased movies Revenge of Diaboromon, Runaway Locomon, Battle of Adventurers, and Island of Lost Digimon. In Japan, Digital Monster X-Evolution, the eighth TV movie, was released on January 3, 2005, and on December 23, 2005 at Jump Festa 2006, the fifth series, Digimon Savers was announced for Japan to begin airing after a three-year hiatus of the show. A sixth television series, Digimon Xros Wars, began airing in 2010, and was followed by a second season, which started on October 2, 2011 as a direct sequel to Digimon Xros Wars.


What is the name of the second Digimon series?


When was the movie Digital Monster X-Evolution released?


When did Digimon Xros Wars begin airing?


When did the first digimon series begin airing in japan?

The first Digimon television series, which began airing on March 7, 1999 in Japan on Fuji TV and Kids Station and on August 14, 1999 in the United States on Fox Kids dubbed by Saban Entertainment for the North American English version. Its premise is a group of 7 kids who, while at summer camp, travel to the Digital World, inhabited by creatures known as Digital Monsters, or Digimon, learning they are chosen to be "DigiDestined" ("Chosen Children" in the Japanese version) to save both the Digital and Real World from evil. Each Kid was given a Digivice which selected them to be transported to the DigiWorld and was destined to be paired up with a Digimon Partner, such as Tai being paired up with Agumon and Matt with Gabumon. The children are helped by a mysterious man/digimon named Gennai, who helps them via hologram. The Digivices help their Digimon allies to Digivolve into stronger creatures in times of peril. The Digimon usually reached higher forms when their human partners are placed in dangerous situations, such as fighting the evil forces of Devimon, Etemon and Myotismon in their Champion forms. Later, each character discovered a crest that each belonged to a person; Tai the Crest of Courage, Matt the Crest of Friendship, Sora the Crest of Love, Izzy the Crest of Knowledge, Mimi the Crest of Sincerity, Joe the Crest of Reliability, T.K. the Crest of Hope, and later Kari the Crest of Light which allowed their Digimon to digivolve into their Ultimate forms. The group consisted of seven original characters: Taichi "Tai" Kamiya, Yamato "Matt" Ishida, Sora Takenouchi, Koushiro "Izzy" Izumi, Mimi Tachikawa, Joe Kido, and Takeru "T.K." Takaishi. Later on in the series, an eighth character was introduced: Hikari "Kari" Kamiya (who is Taichi's younger sister).


When did Digimon begin airing in America?


How many people are in the original Digimon?


When did the second series of Digimon air?

The second Digimon series is direct continuation of the first one, and began airing on April 2, 2000. Three years later, with most of the original DigiDestined now in high school at age fourteen, the Digital World was supposedly secure and peaceful. However, a new evil has appeared in the form of the Digimon Emperor (Digimon Kaiser) who as opposed to previous enemies is a human just like the DigiDestined. The Digimon Emperor has been enslaving Digimon with Dark Rings and Control Spires and has somehow made regular Digivolution impossible. However, five set Digi-Eggs with engraved emblems had been appointed to three new DigiDestined along with T.K. and Kari, two of the DigiDestined from the previous series. This new evolutionary process, dubbed Armor Digivolution helps the new DigiDestined to defeat evil lurking in the Digital World. Eventually, the DigiDestined defeat the Digimon Emperor, more commonly known as Ken Ichijouji on Earth, only with the great sacrifice of Ken's own Digimon, Wormmon. Just when things were thought to be settled, new Digimon enemies made from the deactivated Control Spires start to appear and cause trouble in the Digital World. To atone for his past mistakes, Ken joins the DigiDestined, being a DigiDestined himself, with his Partner Wormmon revived to fight against them. They soon save countries including France and Australia from control spires and defeat MaloMyotismon (BelialVamdemon), the digivolved form of Myotismon (Vamdemon) from the previous series. They stop the evil from destroying the two worlds, and at the end, every person on Earth gains their own Digimon partner.


What age are the original DigiDestined now that they are in High School?


Who is the new evil force that has been enslaving people?


What did Ken do in order to atone for his mistakes?


When did the third Digimon series begin?

The third Digimon series, which began airing on April 1, 2001, is set largely in a "real world" where the Adventure and Adventure 02 series are television shows, and where Digimon game merchandise (based on actual items) become key to providing power boosts to real Digimon which appear in that world. The plot revolves around three Tamers, Takato Matsuki, Rika Nonaka, and Henry Wong. It began with Takato creating his own Digimon partner by sliding a mysterious blue card through his card reader, which then became a D-Power. Guilmon takes form from Takato's sketchings of a new Digimon. (Tamers’ only human connection to the Adventure series is Ryo Akiyama, a character featured in some of the Digimon video games and who made an appearance in some occasions of the Adventure story-line.) Some of the changes in this series include the way the Digimon digivolve with the introduction of Biomerge-Digivolution and the way their "Digivices" work. In this series, the Tamers can slide game cards through their "Digivices" and give their Digimon partners certain advantages, as in the card game. This act is called "Digi-Modify" (Card Slash in the Japanese version). The same process was often used to Digivolve the Digimon, but as usual, emotions play a big part in the digivolving process. Unlike the two seasons before it and most of the seasons that followed, Digimon Tamers takes a darker and more realistic approach to its story featuring Digimon who do not reincarnate after their deaths and more complex character development in the original Japanese. The anime has become controversial over the decade, with debates about how appropriate this show actually is for its "target" audience, especially due to the Lovecraftian nature of the last arc. The English dub is more lighthearted dialogue-wise, though still not as much as previous series.


What can tamers do in order to give their partners advantages?


What is the act called of giving partners advantages in Digimon?


When did the fourth series of Digimon begin?

The fourth Digimon series, which began airing on April 7, 2002, radically departs from the previous three by focusing on a new and very different kind of evolution, Spirit Evolution, in which the human characters use their D-Tectors (this series' Digivice) to transform themselves into special Digimon called Legendary Warriors, detracting from the customary formula of having digital partners. After receiving unusual phone messages from Ophanimon (one of the three ruling Digimon alongside Seraphimon and Cherubimon) Takuya Kanbara, Koji Minamoto, Junpei Shibayama, Zoe Orimoto, Tommy Himi, and Koichi Kimura go to a subway station and take a train to the Digital World. Summoned by Ophanimon, the Digidestined realize that they must find the ten legendary spirits and stop the forces of Cherubimon from physically destroying the Digital World. After finding the ten spirits of the Legendary Warriors and defeating Mercurymon, Grumblemon, Ranamon, and Arbormon, they finally end up fighting Cherubimon hoping to foil his effort to dominate the Digital World. After the defeat of Cherubimon, the Digidestined find they must face an even greater challenge as they try to stop the Royal Knights—Dynasmon and Crusadermon—from destroying the Digital World and using the collected data to revive the original ruler of the Digital World: the tyrannical Lucemon. Ultimately the Digidestined fail in preventing Lucemon from reawakening but they do manage to prevent him from escaping into the Real World. In the final battle, all of the legendary spirits the digidestined have collected thus far merge and create Susanoomon. With this new form, the digidestined are able to effectively defeat Lucemon and save the Digital World. In general, Frontier has a much lighter tone than that of Tamers, yet remains darker than Adventure and Adventure 02.


What was the main focus surrounding the fourth series?


What did the characters use to transform themselves into special Digimons?


After the characters transformed into special Digimons, what were they called?


How long did Digimon stay off the air before returning?

After a three-year hiatus, a fifth Digimon series began airing on April 2, 2006. Like Frontier, Savers has no connection with the previous installments, and also marks a new start for the Digimon franchise, with a drastic change in character designs and story-line, in order to reach a broader audience. The story focuses on the challenges faced by the members of D.A.T.S. ("Digital Accident Tactics Squad"), an organization created to conceal the existence of the Digital World and Digimon from the rest of mankind, and secretly solve any Digimon-related incidents occurring on Earth. Later the D.A.T.S. is dragged into a massive conflict between Earth and the Digital World, triggered by an ambitious human scientist named Akihiro Kurata, determined to make use of the Digimon for his own personal gains. The English version was dubbed by Studiopolis and it premiered on the Jetix block on Toon Disney on October 1, 2007. Digivolution in Data Squad requires the human partner's DNA ("Digital Natural Ability" in the English version and "Digisoul" in the Japanese version) to activate, a strong empathy with their Digimon and a will to succeed. 'Digimon Savers' also introduces a new form of digivolving called Burst Mode which is essentially the level above Mega (previously the strongest form a digimon could take). Like previously in Tamers, this plot takes on a dark tone throughout the story and the anime was aimed, originally in Japan, at an older audience consisting of late teens and people in their early twenties from ages 16 to 21. Because of that, along with the designs, the anime being heavily edited and localized for western US audiences like past series, and the English dub being aimed mostly toward younger audiences of children aged 6 to 10 and having a lower TV-Y7-FV rating just like past dubs, Studiopolis dubbed the anime on Jetix with far more edits, changes, censorship, and cut footage. This included giving the Japanese characters full Americanized names and American surnames as well as applying far more Americanization (Marcus Damon as opposed to the Japanese Daimon Masaru), cultural streamlining and more edits to their version similar to the changes 4Kids often made (such as removal of Japanese text for the purpose of cultural streamlining). Despite all that, the setting of the country was still in Japan and the characters were Japanese in the dub. This series was the first to show any Japanese cultural concepts that were unfamiliar with American audiences (such as the manju), which were left unedited and used in the English dub. Also despite the heavy censorship and the English dub aimed at young children, some of the Digimon's attacks named after real weapons such as RizeGreymon's Trident Revolver are not edited and used in the English dub. Well Go USA released it on DVD instead of Disney. The North American English dub was televised on Jetix in the U.S. and on the Family Channel in Canada.


What was the main focus of the 5th season?


What age group did the season target with its darker theme?


What was the original target age for the Digimon series?


How long after the 5th season did the next one start?

Three and a quarter years after the end of the fifth series, a new sixth series was confirmed by Bandai for the Digimon anime, its official name of the series revealed in the June issue of Shueisha's V Jump magazine being Digimon Xros Wars. It began airing in Japan on TV Asahi from July 6, 2010 onwards. Reverting to the design style of the first four series as well as the plot taking on the younger, lighter tone present in series one, two and four throughout the story. The story follows a boy named Mikey Kudō (Taiki Kudo in Japan) who, along with his friends, ends up in the Digital World where they meet Shoutmon and his Digimon friends. Wielding a digivice known as a Fusion Loader (Xros Loader in Japan), Mikey is able to combine multiple Digimon onto one to enhance his power, Shoutmon being the usual core of the combination, using a technique known as 'DigiFuse' (Digi-Xros in Japan). Forming Team Fusion Fighters (Team Xros Heart in Japan), Mikey, Shoutmon and their friends travel through the Digital World to liberate it from the evil Bagra Army, led by Bagramon(Lord Bagra in English), and Midnight, a shady group led by AxeKnightmon with Nene as a figurehead before joining the Fusion Fighters. The Fusion Fighters also finds themselves at odds with Blue Flare, led by Christopher Aonuma (Kiriha Anouma in Japan). The second arc of Xros Wars was subtitled The Evil Death Generals and the Seven Kingdoms. It saw the main cast reshuffled with a new wardrobe while Angie (Akari in Japan) and Jeremy (Zenjiro in Japan) stay behind in the Human World; thus making Mikey, Christopher and Nene the lead protagonists as they set off to face the Seven Death Generals of the Bagra Army and AxeKnightmon's new pawn: Nene's brother Ewan (Yuu in Japan). A new evolution known as Super Digivolution was introduced at the end of the first arc. The English dub of the series began airing on Nickelodeon on September 7, 2013, which is produced by Saban Brands.


When did the sixth season of Digimon begin airing?


Who is the main character in the sixth Digimon series?


Who did the Fusion fighters find themselves in battle with?


When did the English dub for the sixth season start airing?


When was the sequel announcement for the third arc?

On August 17, 2011, Shueisha's V-Jump magazine announced a sequel set one year later, a third arc of Xros Wars subtitled The Young Hunters Who Leapt Through Time, which aired from October 2, 2011 to March 25, 2012, following on from the previous arc. It focuses on a new protagonist, Tagiru Akashi and his partner Gumdramon who embark on a new journey with an older Mikey, Shoutmon, an older Ewan and the revived Damemon, along with other new comrades as they deal with a hidden dimension that lies between the Human World and the Digital World called DigiQuartz. The series finale reintroduces the heroes of the previous five seasons as they all come together and help the current heroes in the final battle due to the fact that the DigiQuartz is essentially a tear in Space and Time, allowing all of the Digimon universes to converge.


What was the original run of the third arc of Digimon?


Who was the main character in the third arc series?


What is the dimension called between the human world and digital world?


How long after Digimon Fusion was a new series announced?

A new Digimon series was announced 30 months after the end of Digimon Fusion at a 15th anniversary concert and theater event for the franchise in August 2014. The series announced the return of the protagonists from the original Digimon Adventure series, most of them now as high school students. A countdown clicking game was posted on the show's official website, offering news when specific clicks were met. On December 13, 2014 the series title and a key visual featuring character designs by Atsuya Uki were revealed with Keitaro Motonaga announced as director with a tentative premiere date of Spring, 2015. However, on May 6, 2015, it was announced that tri. would not be a television series, but rather a 6-part theatrical film series. The films are being streamed in episodic format outside Japan by Crunchyroll and Hulu from the same day they premiere on Japanese theaters.


When was the 15th year anniversary held for Digimon?


Rather than a TV series, What kind of series would the Digimon become?


Where are you able to watch the new series when it is released?


How soon after did another series start after the Digimon Adventure 02?

The series is set three years after the events of Digimon Adventure 02, when Digimon who turn rogue by a mysterious infection appear to wreak havoc in the Human World. Tai and the other DigiDestined from the original series reunite with their partners and start fighting back with support from the Japanese government, while Davis, Yolei, Cody and Ken are defeated by a powerful enemy called Alphamon and disappear without a trace. Tai and the others also meet another DigiDestined called Meiko Mochizuki and her partner Meicoomon who become their friends, until Meicoomon turns hostile as well and flees after an encounter with Ken, who reappears suddenly, once again as the Digimon Emperor. The film series also feature several DigiDestined having their partners Digivolve up to the Mega level for the first time, a feat only Tai and Matt had achieved previously.


Whats the name of the group that defeats Cody and Ken?


What happened for the first time to the DigiDestined in the film series?


How many Digimon movies have been released in Japan?

There have been nine Digimon movies released in Japan. The first seven were directly connected to their respective anime series; Digital Monster X-Evolution originated from the Digimon Chronicle merchandise line. All movies except X-Evolution and Ultimate Power! Activate Burst Mode have been released and distributed internationally. Digimon: The Movie, released in the U.S. and Canada territory by Fox Kids through 20th Century Fox on October 6, 2000, consists of the union of the first three Japanese movies.


How many movies were directly connected to the anime series?


What year was Digimon: The movie released in the US/Canada?


What magazine were given their own original stories of Digimon?

The European publishing company, Panini, approached Digimon in different ways in different countries. While Germany created their own adaptations of episodes, the United Kingdom (UK) reprinted the Dark Horse titles, then translated some of the German adaptations of Adventure 02 episodes. Eventually the UK comics were given their own original stories, which appeared in both the UK's official Digimon Magazine and the official UK Fox Kids companion magazine, Wickid. These original stories only roughly followed the continuity of Adventure 02. When the comic switched to the Tamers series the storylines adhered to continuity more strictly; sometimes it would expand on subject matter not covered by the original Japanese anime (such as Mitsuo Yamaki's past) or the English adaptations of the television shows and movies (such as Ryo's story or the movies that remained undubbed until 2005). In a money saving venture, the original stories were later removed from Digimon Magazine, which returned to printing translated German adaptations of Tamers episodes. Eventually, both magazines were cancelled.


What series did the UK magazine storyline follow?


What happened to the magazines after their run of Digimon?


What did the Digimon series end up having lots of during the series?

The Digimon series has a large number of video games which usually have their own independent storylines with a few sometimes tying into the stories of the anime series or manga series. The games consists of a number of genres including life simulation, adventure, video card game, strategy and racing games, though they are mainly action role-playing games. The games released in North America are: Digimon World, Digimon World 2, Digimon World 3, Digimon World 4, Digimon Digital Card Battle, Digimon Rumble Arena, Digimon Rumble Arena 2, Digimon Battle Spirit, Digimon Battle Spirit 2, Digimon Racing, Digimon World DS, Digimon World Data Squad, Digimon World Dawn and Dusk, Digimon World Championship, and Digimon Masters.


What were the first two North American games released?


Name one of the genres from any of the Digimon video games?


In what year did Bandai post information about a reboot on his website?

In 2011, Bandai posted a countdown on a teaser site. Once the countdown was finished, it revealed a reboot of the Digimon World series titled Digimon World Re:Digitize. An enhanced version of the game released on Nintendo 3DS as Digimon World Re:Digitize Decode in 2013. Another role-playing game by the name Digimon Story: Cyber Sleuth is set for release in 2015 for PlayStation Vita. It is part of the Digimon Story sub-series, originally on Nintendo DS and has also been released with English subtitles in North America.


What year is the video game Digimon Story: Cyber Sleuth set to be released?


When was the Nintendo 3DS Digimon World Re:Digitize released?


A glacier (US /ˈɡleɪʃər/ or UK /ˈɡlæsiə/) is a persistent body of dense ice that is constantly moving under its own weight; it forms where the accumulation of snow exceeds its ablation (melting and sublimation) over many years, often centuries. Glaciers slowly deform and flow due to stresses induced by their weight, creating crevasses, seracs, and other distinguishing features. They also abrade rock and debris from their substrate to create landforms such as cirques and moraines. Glaciers form only on land and are distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water.


Do glaciers form on land, in the sea, or a combination of both?


Which types of ice form on a body of water's surface?


What causes glaciers to deform and flow?


What are some distinguishing glacial features?


How much glacial ice is found surrounding the poles?

On Earth, 99% of glacial ice is contained within vast ice sheets in the polar regions, but glaciers may be found in mountain ranges on every continent except Australia, and on a few high-latitude oceanic islands. Between 35°N and 35°S, glaciers occur only in the Himalayas, Andes, Rocky Mountains, a few high mountains in East Africa, Mexico, New Guinea and on Zard Kuh in Iran. Glaciers cover about 10 percent of Earth's land surface. Continental glaciers cover nearly 13,000,000 km2 (5×10^6 sq mi) or about 98 percent of Antarctica's 13,200,000 km2 (5.1×10^6 sq mi), with an average thickness of 2,100 m (7,000 ft). Greenland and Patagonia also have huge expanses of continental glaciers.


Glaciers are found in mountain ranges on every continent except for which outlier?


How much of Earth's land surface do glaciers cover?


What is the average thickness of an Antartican glacier?


What percent of Antartica's land is covered by glaciers?


Do Earth's lakes or glaciers hold the most freshwater?

Glacial ice is the largest reservoir of freshwater on Earth. Many glaciers from temperate, alpine and seasonal polar climates store water as ice during the colder seasons and release it later in the form of meltwater as warmer summer temperatures cause the glacier to melt, creating a water source that is especially important for plants, animals and human uses when other sources may be scant. Within high altitude and Antarctic environments, the seasonal temperature difference is often not sufficient to release meltwater.


What causes glaciers to release meltwater?


In which area are summer temperatures not high enough to release meltwater from glaciers?


Under what circumstances would humans require water from a glacier?


At what dimensions are glaciers called ice sheets or continental glaciers?

Glacial bodies larger than 50,000 km2 (19,000 sq mi) are called ice sheets or continental glaciers. Several kilometers deep, they obscure the underlying topography. Only nunataks protrude from their surfaces. The only extant ice sheets are the two that cover most of Antarctica and Greenland. They contain vast quantities of fresh water, enough that if both melted, global sea levels would rise by over 70 m (230 ft). Portions of an ice sheet or cap that extend into water are called ice shelves; they tend to be thin with limited slopes and reduced velocities. Narrow, fast-moving sections of an ice sheet are called ice streams. In Antarctica, many ice streams drain into large ice shelves. Some drain directly into the sea, often with an ice tongue, like Mertz Glacier.


How much would global sea levels rise if Greenland and Antartica's glaciers were to melt?


What is the term for ice that protrude's from a glacier's surface?


Narrow, fast-moving pathways on an ice sheet are called what?


What are glaciers called that end in the sea?

Tidewater glaciers are glaciers that terminate in the sea, including most glaciers flowing from Greenland, Antarctica, Baffin and Ellesmere Islands in Canada, Southeast Alaska, and the Northern and Southern Patagonian Ice Fields. As the ice reaches the sea, pieces break off, or calve, forming icebergs. Most tidewater glaciers calve above sea level, which often results in a tremendous impact as the iceberg strikes the water. Tidewater glaciers undergo centuries-long cycles of advance and retreat that are much less affected by the climate change than those of other glaciers.


Most glaciers from Greenland, Antarctica, and Southeast Alaska are of which type?


Are tidewater glaciers more or less affected by climate change than other glaciers?


Do tidewater glaciers calve above or below sea level?


From where is the temperature of a glacier measured?

Thermally, a temperate glacier is at melting point throughout the year, from its surface to its base. The ice of a polar glacier is always below freezing point from the surface to its base, although the surface snowpack may experience seasonal melting. A sub-polar glacier includes both temperate and polar ice, depending on depth beneath the surface and position along the length of the glacier. In a similar way, the thermal regime of a glacier is often described by the temperature at its base alone. A cold-based glacier is below freezing at the ice-ground interface, and is thus frozen to the underlying substrate. A warm-based glacier is above or at freezing at the interface, and is able to slide at this contact. This contrast is thought to a large extent to govern the ability of a glacier to effectively erode its bed, as sliding ice promotes plucking at rock from the surface below. Glaciers which are partly cold-based and partly warm-based are known as polythermal.


Which type of glacier is above or at freezing at it's interface and is able to slide?


What temperature makes a glacier polythermal?


What temperature determines a polar glacier?


What temperature characteristic determines a temperate glacier?


Under what circumstances do glaciers form?

Glaciers form where the accumulation of snow and ice exceeds ablation. The area in which a glacier forms is called a cirque (corrie or cwm) - a typically armchair-shaped geological feature (such as a depression between mountains enclosed by arêtes) - which collects and compresses through gravity the snow which falls into it. This snow collects and is compacted by the weight of the snow falling above it forming névé. Further crushing of the individual snowflakes and squeezing the air from the snow turns it into 'glacial ice'. This glacial ice will fill the cirque until it 'overflows' through a geological weakness or vacancy, such as the gap between two mountains. When the mass of snow and ice is sufficiently thick, it begins to move due to a combination of surface slope, gravity and pressure. On steeper slopes, this can occur with as little as 15 m (50 ft) of snow-ice.


How much ice and snow is minimally necessary to begin to slide on steep glaciers?


What characteristics determine glacial zones?

Glaciers are broken into zones based on surface snowpack and melt conditions. The ablation zone is the region where there is a net loss in glacier mass. The equilibrium line separates the ablation zone and the accumulation zone; it is the altitude where the amount of new snow gained by accumulation is equal to the amount of ice lost through ablation. The upper part of a glacier, where accumulation exceeds ablation, is called the accumulation zone. In general, the accumulation zone accounts for 60–70% of the glacier's surface area, more if the glacier calves icebergs. Ice in the accumulation zone is deep enough to exert a downward force that erodes underlying rock. After a glacier melts, it often leaves behind a bowl- or amphitheater-shaped depression that ranges in size from large basins like the Great Lakes to smaller mountain depressions known as cirques.


Which glacial zone area reports a net-loss in glacial mass?


What is the name of the line seperating the ablation zone from the accumulation zone?


How much glacial surface area is typically considered accumulation zone?


The top 50 m (160 ft) of a glacier are rigid because they are under low pressure. This upper section is known as the fracture zone and moves mostly as a single unit over the plastically flowing lower section. When a glacier moves through irregular terrain, cracks called crevasses develop in the fracture zone. Crevasses form due to differences in glacier velocity. If two rigid sections of a glacier move at different speeds and directions, shear forces cause them to break apart, opening a crevasse. Crevasses are seldom more than 46 m (150 ft) deep but in some cases can be 300 m (1,000 ft) or even deeper. Beneath this point, the plasticity of the ice is too great for cracks to form. Intersecting crevasses can create isolated peaks in the ice, called seracs.


Most crevices are no deeper than what measure?


Which crevasses form on the edge of the glacier?

Crevasses can form in several different ways. Transverse crevasses are transverse to flow and form where steeper slopes cause a glacier to accelerate. Longitudinal crevasses form semi-parallel to flow where a glacier expands laterally. Marginal crevasses form from the edge of the glacier, due to the reduction in speed caused by friction of the valley walls. Marginal crevasses are usually largely transverse to flow. Moving glacier ice can sometimes separate from stagnant ice above, forming a bergschrund. Bergschrunds resemble crevasses but are singular features at a glacier's margins.


Why do marginal crevasses form on the edge of a glacier?


How are bergschrunds different than crevasses?


In what area of Greenland can glaciers move 20-30m per day?

Mean speeds vary greatly, but is typically around 1 m (3 ft) per day. There may be no motion in stagnant areas; for example, in parts of Alaska, trees can establish themselves on surface sediment deposits. In other cases, glaciers can move as fast as 20–30 m (70–100 ft) per day, such as in Greenland's Jakobshavn Isbræ (Greenlandic: Sermeq Kujalleq). Velocity increases with increasing slope, increasing thickness, increasing snowfall, increasing longitudinal confinement, increasing basal temperature, increasing meltwater production and reduced bed hardness.


Increasing slope, thickness, snowfall, longitudinal confinement, basal temperature, and meltwater production result in increased what?


How far do glaciers generally move per day?


Why are some glaciers stagnant in Alaska?


A few glaciers have periods of very rapid advancement called surges. These glaciers exhibit normal movement until suddenly they accelerate, then return to their previous state. During these surges, the glacier may reach velocities far greater than normal speed. These surges may be caused by failure of the underlying bedrock, the pooling of meltwater at the base of the glacier — perhaps delivered from a supraglacial lake — or the simple accumulation of mass beyond a critical "tipping point". Temporary rates up to 90 m (300 ft) per day have occurred when increased temperature or overlying pressure caused bottom ice to melt and water to accumulate beneath a glacier.


At what rate have glaciers travelled during surges?


How far does a glacier have to move to cause glacial earthquakes?

In glaciated areas where the glacier moves faster than one km per year, glacial earthquakes occur. These are large scale temblors that have seismic magnitudes as high as 6.1. The number of glacial earthquakes in Greenland peaks every year in July, August and September and is increasing over time. In a study using data from January 1993 through October 2005, more events were detected every year since 2002, and twice as many events were recorded in 2005 as there were in any other year. This increase in the numbers of glacial earthquakes in Greenland may be a response to global warming.


How high can the seismic magnitude be of a glacial earthquake?


Are Greenland's glacial earthquakes increasing or decreasing as time goes on?


During which months do glacial earthquakes peak in Greenland?


In what year were twice as many glacial earthquakes seen than in any other year in Greenland?


Ogives are alternating wave crests and valleys that appear as dark and light bands of ice on glacier surfaces. They are linked to seasonal motion of glaciers; the width of one dark and one light band generally equals the annual movement of the glacier. Ogives are formed when ice from an icefall is severely broken up, increasing ablation surface area during summer. This creates a swale and space for snow accumulation in the winter, which in turn creates a ridge. Sometimes ogives consist only of undulations or color bands and are described as wave ogives or band ogives.


What does the width of one dark and one light band measure?


Under what conditions are ogives called wave or band ogives?


Glaciers are present on every continent and approximately fifty countries, excluding those (Australia, South Africa) that have glaciers only on distant subantarctic island territories. Extensive glaciers are found in Antarctica, Chile, Canada, Alaska, Greenland and Iceland. Mountain glaciers are widespread, especially in the Andes, the Himalayas, the Rocky Mountains, the Caucasus, and the Alps. Mainland Australia currently contains no glaciers, although a small glacier on Mount Kosciuszko was present in the last glacial period. In New Guinea, small, rapidly diminishing, glaciers are located on its highest summit massif of Puncak Jaya. Africa has glaciers on Mount Kilimanjaro in Tanzania, on Mount Kenya and in the Rwenzori Mountains. Oceanic islands with glaciers occur on Iceland, Svalbard, New Zealand, Jan Mayen and the subantarctic islands of Marion, Heard, Grande Terre (Kerguelen) and Bouvet. During glacial periods of the Quaternary, Taiwan, Hawaii on Mauna Kea and Tenerife also had large alpine glaciers, while the Faroe and Crozet Islands were completely glaciated.


Which sub-antarctic islands have glaciers?


Do glaciers require permanent snow or only temporary coverage?

The permanent snow cover necessary for glacier formation is affected by factors such as the degree of slope on the land, amount of snowfall and the winds. Glaciers can be found in all latitudes except from 20° to 27° north and south of the equator where the presence of the descending limb of the Hadley circulation lowers precipitation so much that with high insolation snow lines reach above 6,500 m (21,330 ft). Between 19˚N and 19˚S, however, precipitation is higher and the mountains above 5,000 m (16,400 ft) usually have permanent snow.


Between which north latitudes are glaciers not found?


Between which latitudes to mountains tend to have permanent snow?


Why do mountains between 19N and 19S tend to have snow?


Which areas in Antartica are considered polar deserts?

Even at high latitudes, glacier formation is not inevitable. Areas of the Arctic, such as Banks Island, and the McMurdo Dry Valleys in Antarctica are considered polar deserts where glaciers cannot form because they receive little snowfall despite the bitter cold. Cold air, unlike warm air, is unable to transport much water vapor. Even during glacial periods of the Quaternary, Manchuria, lowland Siberia, and central and northern Alaska, though extraordinarily cold, had such light snowfall that glaciers could not form.


Why can't glaciers form in polar deserts?


Does cold or warm air facilitate the transport of water vapor?


Glacial abrasion is commonly characterized by glacial striations. Glaciers produce these when they contain large boulders that carve long scratches in the bedrock. By mapping the direction of the striations, researchers can determine the direction of the glacier's movement. Similar to striations are chatter marks, lines of crescent-shape depressions in the rock underlying a glacier. They are formed by abrasion when boulders in the glacier are repeatedly caught and released as they are dragged along the bedrock.


What can scientists deduct from the direction of the striations?


Glacial moraines are formed by the deposition of material from a glacier and are exposed after the glacier has retreated. They usually appear as linear mounds of till, a non-sorted mixture of rock, gravel and boulders within a matrix of a fine powdery material. Terminal or end moraines are formed at the foot or terminal end of a glacier. Lateral moraines are formed on the sides of the glacier. Medial moraines are formed when two different glaciers merge and the lateral moraines of each coalesce to form a moraine in the middle of the combined glacier. Less apparent are ground moraines, also called glacial drift, which often blankets the surface underneath the glacier downslope from the equilibrium line.


What shape do mountain valleys have pre-glacation?

Before glaciation, mountain valleys have a characteristic "V" shape, produced by eroding water. During glaciation, these valleys are widened, deepened, and smoothed, forming a "U"-shaped glacial valley. The erosion that creates glacial valleys eliminates the spurs of earth that extend across mountain valleys, creating triangular cliffs called truncated spurs. Within glacial valleys, depressions created by plucking and abrasion can be filled by lakes, called paternoster lakes. If a glacial valley runs into a large body of water, it forms a fjord.


What gives mountain vallys their characteristic "V" shape before glacation?


What shape do glacial valleys have after being widened by glacation?


At the start of a classic valley glacier is a bowl-shaped cirque, which has escarped walls on three sides but is open on the side that descends into the valley. Cirques are where ice begins to accumulate in a glacier. Two glacial cirques may form back to back and erode their backwalls until only a narrow ridge, called an arête is left. This structure may result in a mountain pass. If multiple cirques encircle a single mountain, they create pointed pyramidal peaks; particularly steep examples are called horns.


Where does ice start accululating in a glacier?


What is a narrow ridge formed by two cirques eroding back to back called?


What are extremely steep cirques called?


How many sides are closed in a typical cirque?


What is another name for roche moutonnee?

Some rock formations in the path of a glacier are sculpted into small hills called roche moutonnée, or "sheepback" rock. Roche moutonnée are elongated, rounded, and asymmetrical bedrock knobs that can be produced by glacier erosion. They range in length from less than a meter to several hundred meters long. Roche moutonnée have a gentle slope on their up-glacier sides and a steep to vertical face on their down-glacier sides. The glacier abrades the smooth slope on the upstream side as it flows along, but tears loose and carries away rock from the downstream side via plucking.


What shape do roche moutonnee have on their "up" side?


What shape do roche moutonnee have on their "down" side?


Where is post-glacial rebound occuring most?

Large masses, such as ice sheets or glaciers, can depress the crust of the Earth into the mantle. The depression usually totals a third of the ice sheet or glacier's thickness. After the ice sheet or glacier melts, the mantle begins to flow back to its original position, pushing the crust back up. This post-glacial rebound, which proceeds very slowly after the melting of the ice sheet or glacier, is currently occurring in measurable amounts in Scandinavia and the Great Lakes region of North America.


What has the ability to depress the crust of the Earth into the mantle?


With what speed does post-glacial rebound occur?


How much of a glacier's thickness is usually involved during crust depression into the mantle?


What is considered the minimal energy increment of a hypothetical oscillator?

First recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1905 the value E, the minimal energy increment of a hypothetical oscillator, was theoretically associated by Einstein with a "quantum" or minimal element of the energy of the electromagnetic wave itself. The light quantum behaved in some respects as an electrically neutral particle, as opposed to an electromagnetic wave. It was eventually called the photon.


In what year was the value E associated by Einstein with quantum theories of energy?


Who discovered an association between the value E and quantum energy?


What did the light quantum behave the same as in laboratory experiments?


What type of charge did a particle have that behaved similarly to light quantum energy?


What is energy abbreviated to in science?


What is frequency also known as in science?


What term describes a small amount of element?


What did the light quantum, in some ways, behave as?


When did Max Planck first recognize the value of the Planck constant?


Which scientist associated the Planck constant with a quantum five years after Planck's recognition?


Instead of an electromagnetic wave, what did the light quantum behave as in some regards?


What is the simple name given to the light quantum today?


What does classical statistics mechanics not define the value of?

Classical statistical mechanics requires the existence of h (but does not define its value). Eventually, following upon Planck's discovery, it was recognized that physical action cannot take on an arbitrary value. Instead, it must be some multiple of a very small quantity, the "quantum of action", now called the Planck constant. Classical physics cannot explain this fact. In many cases, such as for monochromatic light or for atoms, this quantum of action also implies that only certain energy levels are allowed, and values in between are forbidden.


What is required to exist in classical statistics mechanics?


After Planck's findings, what was determined could not take on an arbitrary value?


Classical statistical mechanics requires the existence of what?


What was realized after Planck's discovery?


What is the Planck constant formerly known as?


Regarding atoms, what does the Planck constant imply?


Regarding atoms, what are values in between certain energy levels considered by the Planck constant?


Following Planck's discovery, what was realized about values of physical action?


The Planck constant initially was given what name?


How is the proportional nature of the Planck constant explained?


For certain cases of light or atoms, what does the quantum of action yield?


What are common things like furniture and stationary objects actually made of?

Equivalently, the smallness of the Planck constant reflects the fact that everyday objects and systems are made of a large number of particles. For example, green light with a wavelength of 555 nanometres (the approximate wavelength to which human eyes are most sensitive) has a frequency of 7014540000000000000♠540 THz (7014540000000000000♠540×1012 Hz). Each photon has an energy E = hf = 6981358000000000000♠3.58×10−19 J. That is a very small amount of energy in terms of everyday experience, but everyday experience is not concerned with individual photons any more than with individual atoms or molecules. An amount of light compatible with everyday experience is the energy of one mole of photons; its energy can be computed by multiplying the photon energy by the Avogadro constant, NA ≈ 7023602200000000000♠6.022×1023 mol−1. The result is that green light of wavelength 555 nm has an energy of 7005216000000000000♠216 kJ/mol, a typical energy of everyday life.


Which light wavelength is the human eye most sensitive to?


What color of light is the human eye most sensitive to?


What does the smallness of the Planck constant show?


At about what wavelength of light are human eyes most sensitive?


What frequency does green light with a wavelength of 555 nanmetres have?


How is the energy from one mole of photos computed?


How much energy does a green light of wavelength 555 nm contain?


What is the wavelength of light to which human eyes are most sensitive?


What is the frequency of the light to which the human eye is most sensitive?


How much energy is contained in the light to which human eyes are most sensitive?


What type of radiation was Planck studying in the late 19th century?

In the last years of the nineteenth century, Planck was investigating the problem of black-body radiation first posed by Kirchhoff some forty years earlier. It is well known that hot objects glow, and that hotter objects glow brighter than cooler ones. The electromagnetic field obeys laws of motion similarly to a mass on a spring, and can come to thermal equilibrium with hot atoms. The hot object in equilibrium with light absorbs just as much light as it emits. If the object is black, meaning it absorbs all the light that hits it, then its thermal light emission is maximized.


How many years prior to Planck's study had the scientific community first discussed black body radiation?


What scientist first studied black body radiation?


What is required for the electromagnetic field to come to thermal equilibrium?


What does a hot object in equilibrium absorb as much as it emits?


What was Planck studying in the last part of the nineteenth century?


Who posed the problem of black-body radiation?


Cooler objects glow less than objects that are what?


What does a black object do to any of the light that hits it?


What is maximized as a result of a black object absorbing all the light that hits it?


Planck studied what problem posed originally by Kirchhoff?


If an object is black, what is known about its thermal light emission?


What is known about the light absorption of a hot object in equilibrium with light?


What do scientists assume black body radiation is?

The assumption that black-body radiation is thermal leads to an accurate prediction: the total amount of emitted energy goes up with the temperature according to a definite rule, the Stefan–Boltzmann law (1879–84). But it was also known that the colour of the light given off by a hot object changes with the temperature, so that "white hot" is hotter than "red hot". Nevertheless, Wilhelm Wien discovered the mathematical relationship between the peaks of the curves at different temperatures, by using the principle of adiabatic invariance. At each different temperature, the curve is moved over by Wien's displacement law (1893). Wien also proposed an approximation for the spectrum of the object, which was correct at high frequencies (short wavelength) but not at low frequencies (long wavelength). It still was not clear why the spectrum of a hot object had the form that it has (see diagram).


What kind of prediction does the assumption that black body radiation is thermal lead to?


What type of changes in the light a hot object emits as the object's temperature changes?


What law describes the changes in light emitted by a hot object?


What assumption that black-body radiation is what leads to an accurate prediction?


What does the Stefan-Boltzmann law state?


What about a hot object changes with the temperature?


What rule predicts that emitted energy increases with temperature?


What characteristic of the light emitted by a hot object changes with temperature?


Who discovered the mathematical relationship between peaks and curves of light at different temperatures?


The rule that adjust the curve at different temperatures is known as what?


Wien's spectrum model could not predict accurate at what end of the spectrum?


Before Planck, it was assumed that the energy of a body could take on what value?

Prior to Planck's work, it had been assumed that the energy of a body could take on any value whatsoever – that it was a continuous variable. The Rayleigh–Jeans law makes close predictions for a narrow range of values at one limit of temperatures, but the results diverge more and more strongly as temperatures increase. To make Planck's law, which correctly predicts blackbody emissions, it was necessary to multiply the classical expression by a complex factor that involves h in both the numerator and the denominator. The influence of h in this complex factor would not disappear if it were set to zero or to any other value. Making an equation out of Planck's law that would reproduce the Rayleigh–Jeans law could not be done by changing the values of h, of the Boltzmann constant, or of any other constant or variable in the equation. In this case the picture given by classical physics is not duplicated by a range of results in the quantum picture.


The Rayleigh-Jeans law makes close predictions for what amount of values?


What does Planck's law correctly predict?


In making Planck's law, what was in both the numerator and denominator of the formula that was used?


Planck's work disproved what assumption?


What rule predicted narrow range of energy values at lower temperatures?


Planck's law involved what necessary mathematical step to correctly predict blackbody emission?


Changing values of n, the Boltzmann constant, or other variables resulted in learning what about Planck's law?


The disparity between Planck's law and the Rayleigh-Jeans law led to what conclusion?


Einstein and what other two individuals revisited the black-body problem in 1905?

The black-body problem was revisited in 1905, when Rayleigh and Jeans (on the one hand) and Einstein (on the other hand) independently proved that classical electromagnetism could never account for the observed spectrum. These proofs are commonly known as the "ultraviolet catastrophe", a name coined by Paul Ehrenfest in 1911. They contributed greatly (along with Einstein's work on the photoelectric effect) to convincing physicists that Planck's postulate of quantized energy levels was more than a mere mathematical formalism. The very first Solvay Conference in 1911 was devoted to "the theory of radiation and quanta". Max Planck received the 1918 Nobel Prize in Physics "in recognition of the services he rendered to the advancement of Physics by his discovery of energy quanta".


Who came up with the term, "ultraviolet catastrophe"?


When did Paul Ehrenfest come up with the name "ultraviolet catastrophe"?


When was the first Solvay Conference held?


Who received the Nobel Prize in Physics in 1918?


What did Rayleigh & Jeans and Einstein prove independently in 1905?


What name did Paul Ehrenfest give to the proofs from Einstein and Rayleigh & Jeans?


What was the topic of the first Solvay Conference?


In what year did Planck receive the Nobel Prize in Physics for his discovery of energy quanta?


Who first observed the photoelectric effect?

The photoelectric effect is the emission of electrons (called "photoelectrons") from a surface when light is shone on it. It was first observed by Alexandre Edmond Becquerel in 1839, although credit is usually reserved for Heinrich Hertz, who published the first thorough investigation in 1887. Another particularly thorough investigation was published by Philipp Lenard in 1902. Einstein's 1905 paper discussing the effect in terms of light quanta would earn him the Nobel Prize in 1921, when his predictions had been confirmed by the experimental work of Robert Andrews Millikan. The Nobel committee awarded the prize for his work on the photo-electric effect, rather than relativity, both because of a bias against purely theoretical physics not grounded in discovery or experiment, and dissent amongst its members as to the actual proof that relativity was real.


When was the photoelectric effect first observed?


Who published the first thorough investigation of the photoelectric effect?


Who received the Nobel Prize in 1921 for his work on the photoelectric effect?


What did Einstein with the 1921 Nobel Prize for?


Einstein's paper on the photoelectric effect earned him the Nobel Prize in what year?


Einstein's photoelectric effect work was rewards as opposed to his work on what other topic?


Before Einstein, electromagnetic radiation was considered to behave as what?

Prior to Einstein's paper, electromagnetic radiation such as visible light was considered to behave as a wave: hence the use of the terms "frequency" and "wavelength" to characterise different types of radiation. The energy transferred by a wave in a given time is called its intensity. The light from a theatre spotlight is more intense than the light from a domestic lightbulb; that is to say that the spotlight gives out more energy per unit time and per unit space(and hence consumes more electricity) than the ordinary bulb, even though the colour of the light might be very similar. Other waves, such as sound or the waves crashing against a seafront, also have their own intensity. However, the energy account of the photoelectric effect didn't seem to agree with the wave description of light.


What terms describe different types of radiation?


What other types of wave besides light has its own intensity?


What is the energy transferred by a wave in a given time called?


Prior to Einstein's work, light behavior was modeled as what?


What is the name for the amount of energy transfered by a wave in a given time?


What portion of the photoelectric effect was in disagreement with the believed description of light behavior?


What does it mean for a light source to be more intense than another?


What is emitted as a result of the photoelectric effect?

The "photoelectrons" emitted as a result of the photoelectric effect have a certain kinetic energy, which can be measured. This kinetic energy (for each photoelectron) is independent of the intensity of the light, but depends linearly on the frequency; and if the frequency is too low (corresponding to a photon energy that is less than the work function of the material), no photoelectrons are emitted at all, unless a plurality of photons, whose energetic sum is greater than the energy of the photoelectrons, acts virtually simultaneously (multiphoton effect) Assuming the frequency is high enough to cause the photoelectric effect, a rise in intensity of the light source causes more photoelectrons to be emitted with the same kinetic energy, rather than the same number of photoelectrons to be emitted with higher kinetic energy.


What does the kinetic energy of a photoelectron depend on?


What happens if the photoelectron's frequency is too low?


What is the term used when photoelectrons act virtually at the same time?


What type of energy due photoelectrons emitted due to the photoelectric effect have?


What factor of the initial light source does the energy of the photoelectrons depend on?


When the photon energy is less than the work function of the material the light is shone upon, how many photoelectrons are emitted?


If the photoelectric effect is occuring, increasing the intensity of the light source causes what?


Who introduced the first quantized model of the atom?

Niels Bohr introduced the first quantized model of the atom in 1913, in an attempt to overcome a major shortcoming of Rutherford's classical model. In classical electrodynamics, a charge moving in a circle should radiate electromagnetic radiation. If that charge were to be an electron orbiting a nucleus, the radiation would cause it to lose energy and spiral down into the nucleus. Bohr solved this paradox with explicit reference to Planck's work: an electron in a Bohr atom could only have certain defined energies En


When was the first quantized model of the atom introduced?


Why was the first quantized model of the atom introduced?


In classical electrodynamics, a charge moving in a circle should do what?


Who modeled the atom in 1913, challenging Rutherford's model?


What was predicted to happen to a nucleus-orbiting electron under Rutherford's model?


What statement did Bohr make about the electron of an atom, citing Planck's work?


Who introduced the reduced Planck constant?

Bohr also introduced the quantity , now known as the reduced Planck constant, as the quantum of angular momentum. At first, Bohr thought that this was the angular momentum of each electron in an atom: this proved incorrect and, despite developments by Sommerfeld and others, an accurate description of the electron angular momentum proved beyond the Bohr model. The correct quantization rules for electrons – in which the energy reduces to the Bohr model equation in the case of the hydrogen atom – were given by Heisenberg's matrix mechanics in 1925 and the Schrödinger wave equation in 1926: the reduced Planck constant remains the fundamental quantum of angular momentum. In modern terms, if J is the total angular momentum of a system with rotational invariance, and Jz the angular momentum measured along any given direction, these quantities can only take on the values


What is the reduced Planck constant also known as?


Who helped to give the correct quantization rules for electrons in 1925?


Who helped to give the correct quantization rules for electrons in 1926?


According to Heisenberg and Schrödinger, the reduced Planck constant remains what?


Bohr introduced what value as the quantum of angular momentum?


What incorrect belief did Bohr hold about the reduced Planck constant?


What scientist used matrix mechanics to bring electron behavior in line with the Bohr model?


When was the Schrödinger wave equation proposed?


What measurable value obeys a similar rule of angular momentum?

where the uncertainty is given as the standard deviation of the measured value from its expected value. There are a number of other such pairs of physically measurable values which obey a similar rule. One example is time vs. energy. The either-or nature of uncertainty forces measurement attempts to choose between trade offs, and given that they are quanta, the trade offs often take the form of either-or (as in Fourier analysis), rather than the compromises and gray areas of time series analysis.


What forces measurement attempts to choose between trade-offs, in quanta?


What form do measurement attempt trade-offs for quanta take the form of?


How is uncertainly measured in this experience?


What type of analysis fits the either-or nature of the uncertainty?


What example is given as another paired relationship of uncertainly related to standard deviation?


What is the unit of magentic properties of the electron?

The Bohr magneton and the nuclear magneton are units which are used to describe the magnetic properties of the electron and atomic nuclei respectively. The Bohr magneton is the magnetic moment which would be expected for an electron if it behaved as a spinning charge according to classical electrodynamics. It is defined in terms of the reduced Planck constant, the elementary charge and the electron mass, all of which depend on the Planck constant: the final dependence on h1/2 (r2 > 0.995) can be found by expanding the variables.


What is the unit of magentic properties of atomic nuclei?


The Bohr magneton is the magnetic moment of an electron under what restriction?


What three terms define the Bohr magneton value?


How was the Planck constant calculated in the early 20th century?

In principle, the Planck constant could be determined by examining the spectrum of a black-body radiator or the kinetic energy of photoelectrons, and this is how its value was first calculated in the early twentieth century. In practice, these are no longer the most accurate methods. The CODATA value quoted here is based on three watt-balance measurements of KJ2RK and one inter-laboratory determination of the molar volume of silicon, but is mostly determined by a 2007 watt-balance measurement made at the U.S. National Institute of Standards and Technology (NIST). Five other measurements by three different methods were initially considered, but not included in the final refinement as they were too imprecise to affect the result.


The value quoted here for the Planck constant is based on a measurement in what year?


What method was was used to obtain the measurement?


One other measure involved the molar volume of what element?


What is a main practical difficulty in determining n?

There are both practical and theoretical difficulties in determining h. The practical difficulties can be illustrated by the fact that the two most accurate methods, the watt balance and the X-ray crystal density method, do not appear to agree with one another. The most likely reason is that the measurement uncertainty for one (or both) of the methods has been estimated too low – it is (or they are) not as precise as is currently believed – but for the time being there is no indication which method is at fault.


Which method is at fault or the discrepancy?


Other than the X-ray crystal density method, other methods rely on what two effects?

The theoretical difficulties arise from the fact that all of the methods except the X-ray crystal density method rely on the theoretical basis of the Josephson effect and the quantum Hall effect. If these theories are slightly inaccurate – though there is no evidence at present to suggest they are – the methods would not give accurate values for the Planck constant. More importantly, the values of the Planck constant obtained in this way cannot be used as tests of the theories without falling into a circular argument. Fortunately, there are other statistical ways of testing the theories, and the theories have yet to be refuted.


Why does relying on these effects create concern?


Using Planck constant values from these effects would lead to what logical issue?


What is the saving grace of relying on these theories?


A watt balance is an instrument for comparing two powers, one of which is measured in SI watts and the other of which is measured in conventional electrical units. From the definition of the conventional watt W90, this gives a measure of the product KJ2RK in SI units, where RK is the von Klitzing constant which appears in the quantum Hall effect. If the theoretical treatments of the Josephson effect and the quantum Hall effect are valid, and in particular assuming that RK = h/e2, the measurement of KJ2RK is a direct determination of the Planck constant.


If the effects are valid, for RK = n/e2, what is the measurement of KJ2RK equal to?


The gyromagnetic ratio is the constant proportion between the magentic field and what?

The gyromagnetic ratio γ is the constant of proportionality between the frequency ν of nuclear magnetic resonance (or electron paramagnetic resonance for electrons) and the applied magnetic field B: ν = γB. It is difficult to measure gyromagnetic ratios precisely because of the difficulties in precisely measuring B, but the value for protons in water at 7002298150000000000♠25 °C is known to better than one part per million. The protons are said to be "shielded" from the applied magnetic field by the electrons in the water molecule, the same effect that gives rise to chemical shift in NMR spectroscopy, and this is indicated by a prime on the symbol for the gyromagnetic ratio, γ′p. The gyromagnetic ratio is related to the shielded proton magnetic moment μ′p, the spin number I (I = 1⁄2 for protons) and the reduced Planck constant.


How does the water molecule impact the effect of magnetic fields on protons?


What three factors impact the gyromagnetic ratio?


The gyromagnetic ratio is often difficult to determine due to difficulty accurately determining the value of what?


How many methods of measuring the gyromagnetic ratio are there?

A further complication is that the measurement of γ′p involves the measurement of an electric current: this is invariably measured in conventional amperes rather than in SI amperes, so a conversion factor is required. The symbol Γ′p-90 is used for the measured gyromagnetic ratio using conventional electrical units. In addition, there are two methods of measuring the value, a "low-field" method and a "high-field" method, and the conversion factors are different in the two cases. Only the high-field value Γ′p-90(hi) is of interest in determining the Planck constant.


How do conversion factors compare in "low-field" and "high-field" methods of measuring the gyromagnetic ratio?


Which method is of interest in determining the Planck constant?


Why is the measurement of electric current an issue in the estimate of the gyromagnetic ratio?


The Faraday constant F is the charge of one mole of electrons, equal to the Avogadro constant NA multiplied by the elementary charge e. It can be determined by careful electrolysis experiments, measuring the amount of silver dissolved from an electrode in a given time and for a given electric current. In practice, it is measured in conventional electrical units, and so given the symbol F90. Substituting the definitions of NA and e, and converting from conventional electrical units to SI units, gives the relation to the Planck constant.


How does the Faraday constant relate to the Planck constant?


How is the Farday constant value quickly calculated?


What is the primary method for determining the Avogadro constant?

The X-ray crystal density method is primarily a method for determining the Avogadro constant NA but as the Avogadro constant is related to the Planck constant it also determines a value for h. The principle behind the method is to determine NA as the ratio between the volume of the unit cell of a crystal, measured by X-ray crystallography, and the molar volume of the substance. Crystals of silicon are used, as they are available in high quality and purity by the technology developed for the semiconductor industry. The unit cell volume is calculated from the spacing between two crystal planes referred to as d220. The molar volume Vm(Si) requires a knowledge of the density of the crystal and the atomic weight of the silicon used. The Planck constant is given by


The Avogadro constant is determined to be the ratio between what two factors in the X-ray crystal density method?


What element is used typically to establish Avogadro's constant?


Calculating molar volume requires knowledge of what two factors?


What measurement is deemed most important to redefine in terms of physical constants?

There are a number of proposals to redefine certain of the SI base units in terms of fundamental physical constants. This has already been done for the metre, which is defined in terms of a fixed value of the speed of light. The most urgent unit on the list for redefinition is the kilogram, whose value has been fixed for all science (since 1889) by the mass of a small cylinder of platinum–iridium alloy kept in a vault just outside Paris. While nobody knows if the mass of the International Prototype Kilogram has changed since 1889 – the value 1 kg of its mass expressed in kilograms is by definition unchanged and therein lies one of the problems – it is known that over such a timescale the many similar Pt–Ir alloy cylinders kept in national laboratories around the world, have changed their relative mass by several tens of parts per million, however carefully they are stored, and the more so the more they have been taken out and used as mass standards. A change of several tens of micrograms in one kilogram is equivalent to the current uncertainty in the value of the Planck constant in SI units.


What is the shape of the object that establishes the base unit of the kilogram?


What alloy is the base unit of the kilogram made from?


Where is the base unit for the kilogram kept?


Where would the decision to change the definition of the kilogram have occured at the earliest?

The legal process to change the definition of the kilogram is already underway, but it had been decided that no final decision would be made before the next meeting of the General Conference on Weights and Measures in 2011. (For more detailed information, see kilogram definitions.) The Planck constant is a leading contender to form the basis of the new definition, although not the only one. Possible new definitions include "the mass of a body at rest whose equivalent energy equals the energy of photons whose frequencies sum to 7050135639273999999♠135639274×1042 Hz", or simply "the kilogram is defined so that the Planck constant equals 6966662606895999999♠6.62606896×10−34 J⋅s".


Was the Planck constant the only option for redefining the kilogram?


The mass of a resting body with what energy would be equal to a kilogram?


A kilogram could be definined as having a Planck constant of what value?


What is the largest cable company in the world by revenue?

Comcast Corporation, formerly registered as Comcast Holdings,[note 1] is an American multinational mass media company and is the largest broadcasting and largest cable company in the world by revenue. It is the second largest pay-TV company after the AT&T-DirecTV acquisition, largest cable TV company and largest home Internet service provider in the United States, and the nation's third largest home telephone service provider. Comcast services U.S. residential and commercial customers in 40 states and the District of Columbia. The company's headquarters are located in Philadelphia, Pennsylvania.


What merged companies are the largest pay TV entity in the world?


Comcast is also the largest media company in the United States in what broadband area?


In what areas of the US does Comcast operate?