Commentaries dealing with the zahir (outward aspects) of the text are called tafsir, and hermeneutic and esoteric commentaries dealing with the batin are called ta'wil ("interpretation" or "explanation"), which involves taking the text back to its beginning. Commentators with an esoteric slant believe that the ultimate meaning of the Quran is known only to God. In contrast, Quranic literalism, followed by Salafis and Zahiris, is the belief that the Quran should only be taken at its apparent meaning.[citation needed]

What is the Arabic term for the surface-level aspects of a text?

zahir

What Arabic term applies to interpretations aimed at the deeper, esoteric meanings of a text?

ta'wil

Who is the only one who ever knows the full meaning of Quranic verses in the esoteric view?

God

Which two groups are examples of Muslims who advocate a very literal reading of the Quran?

Salafis and Zahiris

What is the Jewish term for the surface-level aspects of a text?

I'm not sure.

What is the Arabic term for the surface-level aspects of a song?

I'm not sure.

What Arabic term applies to misinterpretations aimed at the deeper, esoteric meanings of a text?

I'm not sure.

Who is the only one who ever knows the partial meaning of Quranic verses in the esoteric view?

I'm not sure.

Which two groups are examples of Muslims who advocate a very unliteral reading of the Quran?

I'm not sure.


The first fully attested complete translations of the Quran were done between the 10th and 12th centuries in Persian. The Samanid king, Mansur I (961-976), ordered a group of scholars from Khorasan to translate the Tafsir al-Tabari, originally in Arabic, into Persian. Later in the 11th century, one of the students of Abu Mansur Abdullah al-Ansari wrote a complete tafsir of the Quran in Persian. In the 12th century, Najm al-Din Abu Hafs al-Nasafi translated the Quran into Persian. The manuscripts of all three books have survived and have been published several times.[citation needed]

In which language was the Quran first translated?

Persian

Which work did scribes from Khorasan translate in the 10th century?

Tafsir al-Tabari

Whose student wrote a Persian tafsir of the Quran in the 11th century?

Abu Mansur Abdullah al-Ansari

Who wrote a Persian translation of the Quran in the 12th century?

Najm al-Din Abu Hafs al-Nasafi

To which dynasty did the king who commissioned the first translation of Quranic texts belong?

Samanid

In which language was the Quran last translated?

I'm not sure.

Which work did scribes from Khorasan translate in the 11th century?

I'm not sure.

Whose student wrote a Persian tafsir of the Quran in the 10th century?

I'm not sure.

Who wrote a Persian translation of the Quran in the 11th century?

I'm not sure.

To which dynasty did the king who commissioned the last translation of Quranic texts belong?

I'm not sure.


Robert of Ketton's 1143 translation of the Quran for Peter the Venerable, Lex Mahumet pseudoprophete, was the first into a Western language (Latin). Alexander Ross offered the first English version in 1649, from the French translation of L'Alcoran de Mahomet (1647) by Andre du Ryer. In 1734, George Sale produced the first scholarly translation of the Quran into English; another was produced by Richard Bell in 1937, and yet another by Arthur John Arberry in 1955. All these translators were non-Muslims. There have been numerous translations by Muslims. The Ahmadiyya Muslim Community has published translations of the Quran in 50 different languages besides a five-volume English commentary and an English translation of the Quran.

In which year was the Quran first translated into a Western language?

Who completed the first Latin version of the Quran?

Robert of Ketton

Whose French translation of the Quran was the model for the first English version?

Andre du Ryer

Which organization offers versions of the Quran in 50 languages?

Ahmadiyya Muslim Community

In which language was Alexander Ross' version of the Quran published in 1649?

English

In which year was the Quran last translated into a Western language?

I'm not sure.

Who completed the last Latin version of the Quran?

I'm not sure.

Whose French translation of the Quran was the model for the last English version?

I'm not sure.

Which organization offers versions of the Quran in 60 languages?

I'm not sure.

In which language was Alexander Ross' version of the Quran published in 1694?

I'm not sure.


The proper recitation of the Quran is the subject of a separate discipline named tajwid which determines in detail how the Quran should be recited, how each individual syllable is to be pronounced, the need to pay attention to the places where there should be a pause, to elisions, where the pronunciation should be long or short, where letters should be sounded together and where they should be kept separate, etc. It may be said that this discipline studies the laws and methods of the proper recitation of the Quran and covers three main areas: the proper pronunciation of consonants and vowels (the articulation of the Quranic phonemes), the rules of pause in recitation and of resumption of recitation, and the musical and melodious features of recitation.

What discipline concerns the way the Quran is correctly recited?

tajwid

Tajwid deals with what aspect of the phonemes in the Quran?

pronunciation

Tajwid describes rules for what noiseless aspect of articulating Quranic verses?

pause in recitation

Rhythm is an example of which features of Quranic recitation covered by tajwid?

musical and melodious

What discipline concerns the way the Quran is incorrectly recited?

I'm not sure.

What discipline concerns the way the Quran is correctly unrecited?

I'm not sure.

Tajwid describes rules for what noiseless aspect of inarticulating Quranic verses?

I'm not sure.

Tajwid deals with what aspect of the phonemes in the Bible?

I'm not sure.

Rhythm is an example of which features of Quranic recitation uncovered by tajwid?

I'm not sure.


Vocalization markers indicating specific vowel sounds were introduced into the Arabic language by the end of the 9th century. The first Quranic manuscripts lacked these marks, therefore several recitations remain acceptable. The variation in readings of the text permitted by the nature of the defective vocalization led to an increase in the number of readings during the 10th century. The 10th-century Muslim scholar from Baghdad, Ibn Mujāhid, is famous for establishing seven acceptable textual readings of the Quran. He studied various readings and their trustworthiness and chose seven 8th-century readers from the cities of Mecca, Medina, Kufa, Basra and Damascus. Ibn Mujahid did not explain why he chose seven readers, rather than six or ten, but this may be related to a prophetic tradition (Muhammad's saying) reporting that the Quran had been revealed in seven "ahruf" (meaning seven letters or modes). Today, the most popular readings are those transmitted by Ḥafṣ (d.796) and Warsh (d. 812) which are according to two of Ibn Mujahid's reciters, Aasim ibn Abi al-Najud (Kufa, d. 745) and Nafi‘ al-Madani (Medina, d. 785), respectively. The influential standard Quran of Cairo (1924) uses an elaborate system of modified vowel-signs and a set of additional symbols for minute details and is based on ʻAsim's recitation, the 8th-century recitation of Kufa. This edition has become the standard for modern printings of the Quran.

The absence of which language feature made early Quranic recitation more diverse?

Vocalization markers

Which Baghdad scholar identified justified seven different Quranic readings?

Ibn Mujāhid

Which recitation is the original basis of the Quran of Cairo?

ʻAsim's

Which century produced the seven readings selected by Ibn Mujāhid?

Which city corresponds to Asim's recitation of the Quran?

Kufa

The absence of which language feature made later Quranic recitation more diverse?

I'm not sure.

Which Baghdad scholar identified unjustified seven different Quranic readings?

I'm not sure.

Which recitation is the later basis of the Quran of Cairo?

I'm not sure.

Which century produced the eight readings selected by Ibn Mujāhid?

I'm not sure.

Which city doesn't correspond to Asim's recitation of the Quran?

I'm not sure.


Before printing was widely adopted in the 19th century, the Quran was transmitted in manuscripts made by calligraphers and copyists. The earliest manuscripts were written in Ḥijāzī-type script. The Hijazi style manuscripts nevertheless confirm that transmission of the Quran in writing began at an early stage. Probably in the ninth century, scripts began to feature thicker strokes, which are traditionally known as Kufic scripts. Toward the end of the ninth century, new scripts began to appear in copies of the Quran and replace earlier scripts. The reason for discontinuation in the use of the earlier style was that it took too long to produce and the demand for copies was increasing. Copyists would therefore chose simpler writing styles. Beginning in the 11th century, the styles of writing employed were primarily the naskh, muhaqqaq, rayḥānī and, on rarer occasions, the thuluth script. Naskh was in very widespread use. In North Africa and Spain, the Maghribī style was popular. More distinct is the Bihari script which was used solely in the north of India. Nastaʻlīq style was also rarely used in Persian world.

Who created Quranic manuscripts before the 19th century?

calligraphers and copyists

What is the name of the thicker-stroked writing used for the Quran beginning in the 9th century?

Kufic scripts

Which was the most widely used script by copyists in the 11th century?

naskh

Where was the Maghribi script most commonly used by Quran copyists?

North Africa and Spain

Which script was only used to copy the Quran by people in northern India?

Bihari

Who created Quranic manuscripts before the 18th century?

I'm not sure.

What is the name of the thicker-stroked writing used for the Quran beginning in the 8th century?

I'm not sure.

Which was the most widely used script by copyists in the 10th century?

I'm not sure.

Where was the Maghribi script least commonly used by Quran copyists?

I'm not sure.

Which script was never used to copy the Quran by people in northern India?

I'm not sure.


In the beginning, the Quran did not have vocalization markings. The system of vocalization, as we know it today, seems to have been introduced towards the end of the ninth century. Since it would have been too costly for most Muslims to purchase a manuscript, copies of the Quran were held in mosques in order to make them accessible to people. These copies frequently took the form of a series of 30 parts or juzʼ. In terms of productivity, the Ottoman copyists provide the best example. This was in response to widespread demand, unpopularity of printing methods and for aesthetic reasons.

In which century were vocalization marking added to the Quran?

ninth century

Where were Quran copies kept for those who could not afford their own?

mosques

What are the parts of the Quran called that are 30 in total?

juzʼ

Which group of Quran copyists produced the most in-demand manuscripts?

Ottoman

In which century were vocalization marking taken from the Quran?

I'm not sure.

Where were Quran copies kept for those who could afford their own?

I'm not sure.

Where weren't Quran copies kept for those who could not afford their own?

I'm not sure.

What are the parts of the Quran called that are 33 in total?

I'm not sure.

Which group of Quran copyists produced the least in-demand manuscripts?

I'm not sure.


According to Sahih al-Bukhari, the Quran was recited among Levantines and Iraqis, and discussed by Christians and Jews, before it was standardized. Its language was similar to the Syriac language.[citation needed] The Quran recounts stories of many of the people and events recounted in Jewish and Christian sacred books (Tanakh, Bible) and devotional literature (Apocrypha, Midrash), although it differs in many details. Adam, Enoch, Noah, Eber, Shelah, Abraham, Lot, Ishmael, Isaac, Jacob, Joseph, Job, Jethro, David, Solomon, Elijah, Elisha, Jonah, Aaron, Moses, Zechariah, John the Baptist and Jesus are mentioned in the Quran as prophets of God (see Prophets of Islam). In fact, Moses is mentioned more in the Quran than any other individual. Jesus is mentioned more often in the Quran than Muhammad, while Mary is mentioned in the Quran more than the New Testament. Muslims believe the common elements or resemblances between the Bible and other Jewish and Christian writings and Islamic dispensations is due to their common divine source,[citation needed] and that the original Christian or Jewish texts were authentic divine revelations given to prophets.

Which Biblical character is the most often mentioned person in the Quran?

Moses

Who has claimed that Christians and Jews had heard and discussed the Quran before it took on its standardized Arabic form?

Sahih al-Bukhari

Which older language is thought to strongly resemble that of the Quran?

Syriac

Which relative of Jesus appears more often in the Quran than the New Testament?

Mary

What do devout Muslims believe is the reason for the overlap of events and characters in the Bible and Quran?

common divine source

Which Biblical character is the least often mentioned person in the Quran?

I'm not sure.

Who hasn't claimed that Christians and Jews had heard and discussed the Quran before it took on its standardized Arabic form?

I'm not sure.

Which older language is thought to weakly resemble that of the Quran?

I'm not sure.

Which relative of Jesus appears less often in the Quran than the New Testament?

I'm not sure.

What do devout Muslims believe is the reason for no overlap of events and characters in the Bible and Quran?

I'm not sure.


According to Tabatabaei, there are acceptable and unacceptable esoteric interpretations. Acceptable ta'wil refers to the meaning of a verse beyond its literal meaning; rather the implicit meaning, which ultimately is known only to God and can't be comprehended directly through human thought alone. The verses in question here refer to the human qualities of coming, going, sitting, satisfaction, anger and sorrow, which are apparently attributed to God. Unacceptable ta'wil is where one "transfers" the apparent meaning of a verse to a different meaning by means of a proof; this method is not without obvious inconsistencies. Although this unacceptable ta'wil has gained considerable acceptance, it is incorrect and cannot be applied to the Quranic verses. The correct interpretation is that reality a verse refers to. It is found in all verses, the decisive and the ambiguous alike; it is not a sort of a meaning of the word; it is a fact that is too sublime for words. God has dressed them with words to bring them a bit nearer to our minds; in this respect they are like proverbs that are used to create a picture in the mind, and thus help the hearer to clearly grasp the intended idea.

What are the two type of ta'wil?

acceptable and unacceptable

Which type of esoteric interpretation involves a transfer by proof of a verse's meaning?

Unacceptable

The implicit meaning of a Quranic verse that is known fully only by God is which type of ta'wil?

Acceptable

What are the three type of ta'wil?

I'm not sure.

What aren't the two type of ta'wil?

I'm not sure.

Which type of esoteric misinterpretation involves a transfer by proof of a verse's meaning?

I'm not sure.

Which type of unesoteric interpretation involves a transfer by proof of a verse's meaning?

I'm not sure.

The explicit meaning of a Quranic verse that is known fully only by God is which type of ta'wil?

I'm not sure.


The Quran most likely existed in scattered written form during Muhammad's lifetime. Several sources indicate that during Muhammad's lifetime a large number of his companions had memorized the revelations. Early commentaries and Islamic historical sources support the above-mentioned understanding of the Quran's early development. The Quran in its present form is generally considered by academic scholars to record the words spoken by Muhammad because the search for variants has not yielded any differences of great significance.[page needed] University of Chicago professor Fred Donner states that "...there was a very early attempt to establish a uniform consonantal text of the Qurʾān from what was probably a wider and more varied group of related texts in early transmission. [...] After the creation of this standardized canonical text, earlier authoritative texts were suppressed, and all extant manuscripts—despite their numerous variants—seem to date to a time after this standard consonantal text was established." Although most variant readings of the text of the Quran have ceased to be transmitted, some still are. There has been no critical text produced on which a scholarly reconstruction of the Quranic text could be based. Historically, controversy over the Quran's content has rarely become an issue, although debates continue on the subject.

Who had begun memorizing Muhammad's revelations in his lifetime?

his companions

What was done to the Quranic text early in its history leaving few markedly different variants?

standardized

Which which university is Fred Donner affiliated?

University of Chicago

The Quran is widely accepted by historians to contain a relatively accurate record of whose words?

Muhammad

Who had begun forgetting Muhammad's revelations in his lifetime?

I'm not sure.

What was done to the Quranic text late in its history leaving few markedly different variants?

I'm not sure.

What was done to the Quranic text early in its history leaving few markedly same variants?

I'm not sure.

Which which university isn't Fred Donner affiliated?

I'm not sure.

The Quran is widely rejected by historians to contain a relatively accurate record of whose words?

I'm not sure.


Sahih al-Bukhari narrates Muhammad describing the revelations as, "Sometimes it is (revealed) like the ringing of a bell" and Aisha reported, "I saw the Prophet being inspired Divinely on a very cold day and noticed the sweat dropping from his forehead (as the Inspiration was over)." Muhammad's first revelation, according to the Quran, was accompanied with a vision. The agent of revelation is mentioned as the "one mighty in power", the one who "grew clear to view when he was on the uppermost horizon. Then he drew nigh and came down till he was (distant) two bows' length or even nearer." The Islamic studies scholar Welch states in the Encyclopaedia of Islam that he believes the graphic descriptions of Muhammad's condition at these moments may be regarded as genuine, because he was severely disturbed after these revelations. According to Welch, these seizures would have been seen by those around him as convincing evidence for the superhuman origin of Muhammad's inspirations. However, Muhammad's critics accused him of being a possessed man, a soothsayer or a magician since his experiences were similar to those claimed by such figures well known in ancient Arabia. Welch additionally states that it remains uncertain whether these experiences occurred before or after Muhammad's initial claim of prophethood.

What physical symptom accompanied Muhammad's revelations?

seizures

What measure of distance described the nearness of the Angel's approach to Mohammad?

two bows' length

In which work did Welch express his belief that Mohammad's physical reaction to the revelation was historically accurate?

Encyclopaedia of Islam

Which people would Mohammad's critics have compared him to at the time?

a possessed man, a soothsayer or a magician

What mental symptom accompanied Muhammad's revelations?

I'm not sure.

What measure of time described the nearness of the Angel's approach to Mohammad?

I'm not sure.

In which work did Welch express his belief that Mohammad's physical reaction to the revelation was historically inaccurate?

I'm not sure.

Which people wouldn't Mohammad's critics have compared him to at the time?

I'm not sure.

Which people would Mohammad's critics haven't compared him to at the time?

I'm not sure.


Muhammad Husayn Tabatabaei says that according to the popular explanation among the later exegetes, ta'wil indicates the particular meaning a verse is directed towards. The meaning of revelation (tanzil), as opposed to ta'wil, is clear in its accordance to the obvious meaning of the words as they were revealed. But this explanation has become so widespread that, at present, it has become the primary meaning of ta'wil, which originally meant "to return" or "the returning place". In Tabatabaei's view, what has been rightly called ta'wil, or hermeneutic interpretation of the Quran, is not concerned simply with the denotation of words. Rather, it is concerned with certain truths and realities that transcend the comprehension of the common run of men; yet it is from these truths and realities that the principles of doctrine and the practical injunctions of the Quran issue forth. Interpretation is not the meaning of the verse—rather it transpires through that meaning, in a special sort of transpiration. There is a spiritual reality—which is the main objective of ordaining a law, or the basic aim in describing a divine attribute—and then there is an actual significance that a Quranic story refers to.

What can interpretation find that lies the behind the apparent events referred to in a Quranic story?

a spiritual reality

What was the original meaning of ta'wil?

"to return" or "the returning place"

What philosophical term corresponds to the type of interpretation in ta'wil?

hermeneutic

What can misinterpretation find that lies the behind the apparent events referred to in a Quranic story?

I'm not sure.

What can interpretation find that lies the behind the inapparent events referred to in a Quranic story?

I'm not sure.

What was the final meaning of ta'wil?

I'm not sure.

What wasn't the original meaning of ta'wil?

I'm not sure.

What biographical term corresponds to the type of interpretation in ta'wil?

I'm not sure.


According to Shia beliefs, those who are firmly rooted in knowledge like Muhammad and the imams know the secrets of the Quran. According to Tabatabaei, the statement "none knows its interpretation except God" remains valid, without any opposing or qualifying clause. Therefore, so far as this verse is concerned, the knowledge of the Quran's interpretation is reserved for God. But Tabatabaei uses other verses and concludes that those who are purified by God know the interpretation of the Quran to a certain extent.

Who do Shia Muslims believe can approach Quranic truths besides God and Muhammad?

imams

According to Shia Muslims, who is the only one who can fully know the a Quranic interpretation?

God

How must God have treated those who are qualified to know Quranic sectets?

purified

Who do Shia Muslims believe can approach Quranic falsehoods besides God and Muhammad?

I'm not sure.

Who do Sunni Muslims believe can approach Quranic truths besides God and Muhammad?

I'm not sure.

According to Sunni Muslims, who is the only one who can fully know the a Quranic interpretation?

I'm not sure.

According to Shia Muslims, who is the only one who can never know the a Quranic interpretation?

I'm not sure.

How must God have treated those who are unqualified to know Quranic sectets?

I'm not sure.


From 1989 through 1996, the total area of the US was listed as 9,372,610 km2 (3,618,780 sq mi) (land + inland water only). The listed total area changed to 9,629,091 km2 (3,717,813 sq mi) in 1997 (Great Lakes area and coastal waters added), to 9,631,418 km2 (3,718,711 sq mi) in 2004, to 9,631,420 km2 (3,718,710 sq mi) in 2006, and to 9,826,630 km2 (3,794,080 sq mi) in 2007 (territorial waters added). Currently, the CIA World Factbook gives 9,826,675 km2 (3,794,100 sq mi), the United Nations Statistics Division gives 9,629,091 km2 (3,717,813 sq mi), and the Encyclopædia Britannica gives 9,522,055 km2 (3,676,486 sq mi)(Great Lakes area included but not coastal waters). These source consider only the 50 states and the Federal District, and exclude overseas territories.

During the period from 1989 - 1996, what was the total are of the US in miles?

3,618,780 sq mi

According to the CIA World Factbook, what is the total area of the US in miles?

3,794,100 sq mi

According to the Encyclopedia Britannica, what is the total area of the US in miles?

3,676,486 sq mi

The total square miles of land only in the United States was 9,372,610 km² during what time period?

I'm not sure.

Currently the World encyclopedia mileage of the United States is what?

I'm not sure.

What encyclopedia includes both the Great Lakes and coastal waters in the United States square mileage?

I'm not sure.

These sources consider overseas territories all fifty states and what?

I'm not sure.


By total area (water as well as land), the United States is either slightly larger or smaller than the People's Republic of China, making it the world's third or fourth largest country. China and the United States are smaller than Russia and Canada in total area, but are larger than Brazil. By land area only (exclusive of waters), the United States is the world's third largest country, after Russia and China, with Canada in fourth. Whether the US or China is the third largest country by total area depends on two factors: (1) The validity of China's claim on Aksai Chin and Trans-Karakoram Tract. Both these territories are also claimed by India, so are not counted; and (2) How US calculates its own surface area. Since the initial publishing of the World Factbook, the CIA has updated the total area of United States a number of times.

Compared to other countries, how large is the US?

third or fourth largest country

Which country is the worlds fourth largest?

Canada

Who may also be the third largest country?

China

By land area only the United States is slightly larger or smaller than what other country?

I'm not sure.

China and the United States are larger than Russia and what other country in total area?

I'm not sure.

My total area land and water whether the United States is the third-largest country depends on what?

I'm not sure.

Since the initial publication of the world factbook Guinness has done what?

I'm not sure.

Brazil is larger than what other two countries?

I'm not sure.


The United States shares land borders with Canada (to the north) and Mexico (to the south), and a territorial water border with Russia in the northwest, and two territorial water borders in the southeast between Florida and Cuba, and Florida and the Bahamas. The contiguous forty-eight states are otherwise bounded by the Pacific Ocean on the west, the Atlantic Ocean on the east, and the Gulf of Mexico to the southeast. Alaska borders the Pacific Ocean to the south, the Bering Strait to the west, and the Arctic Ocean to the north, while Hawaii lies far to the southwest of the mainland in the Pacific Ocean.

Who does the US share land borders with?

Canada (to the north) and Mexico (to the south),

Who does the US share water borders with in the northwest?

Russia

How many contiguous states are there?

forty-eight

Which ocean does Alaska border to the south?

Pacific Ocean

United States shares land borders with Russia Canada and what other country?

I'm not sure.

The contiguous forty-eight states are bound by the Pacific on the east and what ocean on the West?

I'm not sure.

What state borders the bearing straight on the east?

I'm not sure.

Hawaii lays far to the north east in what ocean?

I'm not sure.

The Gulf of Mexico lies to the southwest of what country?

I'm not sure.


The capital city, Washington, District of Columbia, is a federal district located on land donated by the state of Maryland. (Virginia had also donated land, but it was returned in 1849.) The United States also has overseas territories with varying levels of independence and organization: in the Caribbean the territories of Puerto Rico and the U.S. Virgin Islands, and in the Pacific the inhabited territories of Guam, American Samoa, and the Northern Mariana Islands, along with a number of uninhabited island territories.

What is the capital city of the US?

Washington, District of Columbia

Which US state donated Washington, D.C.?

Maryland

What are the US territories overseas located in the Pacific?

Guam, American Samoa, and the Northern Mariana Islands

Which US state also donated territory to Washington, D.C., but had it returned?

Virginia

What is the capital state of the United States?

I'm not sure.

The District of Columbia is on land donated by what two states?

I'm not sure.

What are the uninhabited territories the US has in the Pacific?

I'm not sure.

US territories of Puerto Rico Virgin Islands and Cuba are located where?

I'm not sure.


The five Great Lakes are located in the north-central portion of the country, four of them forming part of the border with Canada, only Lake Michigan situated entirely within United States. The southeast United States contain subtropical forests and, near the gulf coast, mangrove wetlands, especially in Florida. West of the Appalachians lies the Mississippi River basin and two large eastern tributaries, the Ohio River and the Tennessee River. The Ohio and Tennessee Valleys and the Midwest consist largely of rolling hills and productive farmland, stretching south to the Gulf Coast.

How many Great Lakes form a border with Canada?

four

Which of the Great Lakes is entirely located in US territory?

Lake Michigan

Which major river is located west of the Appalachian mountains?

Mississippi River

What type of land makes up the Ohio and Tennessee valleys?

rolling hills and productive farmland

Which section of the US contains subtropical forests and mangrove wetlands?

southeast United States

The five Great Lakes formal border with what country?

I'm not sure.

Which great Lake is located entirely outside of US territory?

I'm not sure.

Which major river is located east of the Appalachian Mountains

I'm not sure.

What are the two large Western tributaries of the Mississippi River?

I'm not sure.

Which section of the US contains tropical forests and mangrove wetlands?

I'm not sure.


The Great Plains lie west of the Mississippi River and east of the Rocky Mountains. A large portion of the country's agricultural products are grown in the Great Plains. Before their general conversion to farmland, the Great Plains were noted for their extensive grasslands, from tallgrass prairie in the eastern plains to shortgrass steppe in the western High Plains. Elevation rises gradually from less than a few hundred feet near the Mississippi River to more than a mile high in the High Plains. The generally low relief of the plains is broken in several places, most notably in the Ozark and Ouachita Mountains, which form the U.S. Interior Highlands, the only major mountainous region between the Rocky Mountains and the Appalachian Mountains.

What area is located in between the Mississippi River and the Rocky Mountains?

The Great Plains

In which area are a large number of the country's agricultural products grown?

the Great Plains

How high does elevation rise in the Great Plains?

a mile high

What is the only major mountain ranged located between the Appalachian Mountains and the Rocky Mountains?

Interior Highlands

What area is located between the Mississippi River and the appellation Mountains?

I'm not sure.

A small portion of the countries what is grown in the Great Plains?

I'm not sure.

The elevation of what is more than a mile high near the Mississippi River?

I'm not sure.

What are the only mountains between the Rocky Mountains and Appellation Mountains?

I'm not sure.

Before being converted to grassland the Great Plains were known for what?

I'm not sure.


The Great Plains come to an abrupt end at the Rocky Mountains. The Rocky Mountains form a large portion of the Western U.S., entering from Canada and stretching nearly to Mexico. The Rocky Mountain region is the highest region of the United States by average elevation. The Rocky Mountains generally contain fairly mild slopes and wider peaks compared to some of the other great mountain ranges, with a few exceptions (such as the Teton Mountains in Wyoming and the Sawatch Range in Colorado). The highest peaks of the Rockies are found in Colorado, the tallest peak being Mount Elbert at 14,440 ft (4,400 m). The Rocky Mountains contain some of the most spectacular, and well known scenery in the world. In addition, instead of being one generally continuous and solid mountain range, it is broken up into a number of smaller, intermittent mountain ranges, forming a large series of basins and valleys.

Which northern country do the Rocky Mountains begin at?

Canada

Which northern country do the Rocky Mountains terminate at?

Mexico

In the US, which region is the highest by elevation?

The Rocky Mountain

In which state are the highest peaks of the Rocky Mountains found?

Colorado

Where did the Great Plains come to a gradual and at?

I'm not sure.

The appellation Mountains are the highest region of what?

I'm not sure.

What mountains generally contain steep slopes and narrow peaks?

I'm not sure.

The Lowes peak of the Rockies is found in what state?

I'm not sure.

What is a low speak of the Rockies?

I'm not sure.


West of the Rocky Mountains lies the Intermontane Plateaus (also known as the Intermountain West), a large, arid desert lying between the Rockies and the Cascades and Sierra Nevada ranges. The large southern portion, known as the Great Basin, consists of salt flats, drainage basins, and many small north-south mountain ranges. The Southwest is predominantly a low-lying desert region. A portion known as the Colorado Plateau, centered around the Four Corners region, is considered to have some of the most spectacular scenery in the world. It is accentuated in such national parks as Grand Canyon, Arches, Mesa Verde National Park and Bryce Canyon, among others. Other smaller Intermontane areas include the Columbia Plateau covering eastern Washington, western Idaho and northeast Oregon and the Snake River Plain in Southern Idaho.

What is the name of the plateau that lies west of the Rocky Mountains?

Intermontane Plateaus

What is the name of the large southern portion of the Intermontane Plateaus?

the Great Basin

What type of flats compose the Great Basin?

salt flats

What region is centered around the Four Corners?

Colorado Plateau

What is the name of the plateau that lies east of the Rocky Mountains?

I'm not sure.

A large semi arid desert lies between Rockies and what?

I'm not sure.

The large northern portion is known as what?

I'm not sure.

The South East is predominantly what?

I'm not sure.


The Intermontane Plateaus come to an end at the Cascade Range and the Sierra Nevada. The Cascades consist of largely intermittent, volcanic mountains, many rising prominently from the surrounding landscape. The Sierra Nevada, further south, is a high, rugged, and dense mountain range. It contains the highest point in the contiguous 48 states, Mount Whitney (14,505 ft or 4,421 m) It is located at the boundary between California's Inyo and Tulare counties, just 84.6 mi or 136.2 km west-northwest of the lowest point in North America at the Badwater Basin in Death Valley National Park at 279 ft or 85 m below sea level.

What is the name of the range where the Intermontane plateaus end?

Cascade Range

What type of mountains compose the Cascades?

volcanic mountains

Which mountain range contains Mount Whitney?

Sierra Nevada

What is the largest point in the Sierra Nevadas?

Mount Whitney

How tall is Mount Whitney?

14,505 ft

What is the name of the range where theIntermontane plateau begins?

I'm not sure.

The Cascades consist largely of overlapping what?

I'm not sure.

What is the name of the high gentle dense mountain range?

I'm not sure.

What mountain range contains the lowest point in a contagious forty-eight states

I'm not sure.

The highest point in North America is and what basin?

I'm not sure.


These areas contain some spectacular scenery as well, as evidenced by such national parks as Yosemite and Mount Rainier. West of the Cascades and Sierra Nevada is a series of valleys, such as the Central Valley in California and the Willamette Valley in Oregon. Along the coast is a series of low mountain ranges known as the Pacific Coast Ranges. Much of the Pacific Northwest coast is inhabited by some of the densest vegetation outside of the Tropics, and also the tallest trees in the world (the Redwoods).

What are two national parks located in the mountainous regions?

Yosemite and Mount Rainier

What is the name of the famous valley located in California?

Central Valley

What is the name of the famous valley located in Oregon?

Willamette Valley

What are the low mountain ranges that are located along the pacific coast called?

Pacific Coast Ranges

What are the tallest trees in the world?

Redwoods

What two national parks are located on the planes?

I'm not sure.

East of the Cascades Sierra Nevada is a series of what?

I'm not sure.

What is the name of the high mountain range along the coast?

I'm not sure.

What are the skinniest trees in the world?

I'm not sure.


The Atlantic coast of the United States is low, with minor exceptions. The Appalachian Highland owes its oblique northeast-southwest trend to crustal deformations which in very early geological time gave a beginning to what later came to be the Appalachian mountain system. This system had its climax of deformation so long ago (probably in Permian time) that it has since then been very generally reduced to moderate or low relief. It owes its present-day altitude either to renewed elevations along the earlier lines or to the survival of the most resistant rocks as residual mountains. The oblique trend of this coast would be even more pronounced but for a comparatively modern crustal movement, causing a depression in the northeast resulting in an encroachment of the sea upon the land. Additionally, the southeastern section has undergone an elevation resulting in the advance of the land upon the sea.

Why does the Appalachian Highland have the terrain it does?

crustal deformations

During what geological period did the Appalachian mountains reach their highest formation point?

Permian time

What is the name of the mountaneous region along the Atlantic cost.

The Appalachian Highland

The Atlantic Coast of what country is high with minor exceptions?

I'm not sure.

What made to see advance on the land in the southeasternAppalachian?

I'm not sure.

What kind of deformation created in northwest Southeast trend in the Appalachian

I'm not sure.

During what geological. That the Appalachian Mountains reach their lowest point

I'm not sure.

The of Appalachian Mountains are low today because of modern what?

I'm not sure.


The east coast Appalachian system, originally forest covered, is relatively low and narrow and is bordered on the southeast and south by an important coastal plain. The Cordilleran system on the western side of the continent is lofty, broad and complicated having two branches, the Rocky Mountain System and the Pacific Mountain System. In between these mountain systems lie the Intermontaine Plateaus. Both the Columbia River and Colorado River rise far inland near the easternmost members of the Cordilleran system, and flow through plateaus and intermontaine basins to the ocean. Heavy forests cover the northwest coast, but elsewhere trees are found only on the higher ranges below the Alpine region. The intermontane valleys, plateaus and basins range from treeless to desert with the most arid region being in the southwest.

What originally covered the east coast of the Appalachians?

forest

What are the two branches of the Cordilleran system?

Rocky Mountain System and the Pacific Mountain System

Which two major rivers are located in the Cordilleran system?

Columbia River and Colorado River

Which region of the Appalachians is the most arid?

southwest

What system is relatively high and wide?

I'm not sure.

The Appalachian system is bordered on the southwest and south by what?

I'm not sure.

The Cordilleran system on the eastern side of the continent is what?

I'm not sure.

What has three branches including the Rocky Mountains system?

I'm not sure.

Light force cover what coast?

I'm not sure.


The Laurentian Highlands, the Interior Plains and the Interior Highlands lie between the two coasts, stretching from the Gulf of Mexico northward, far beyond the national boundary, to the Arctic Ocean. The central plains are divided by a hardly perceptible height of land into a Canadian and a United States portion. It is from the United States side, that the great Mississippi system discharges southward to the Gulf of Mexico. The upper Mississippi and some of the Ohio basin is the semi-arid prairie region, with trees originally only along the watercourses. The uplands towards the Appalachians were included in the great eastern forested area, while the western part of the plains has so dry a climate that its native plant life is scanty, and in the south it is practically barren.

What is one of the two major highlands that stretch from the gulf of mexico to the Arctic ocean?

Laurentian Highlands

How far north do the Interior Highlands reach?

Arctic Ocean

Which two nations are the central plains divided in?

Canadian and a United States

Where does the Mississippi discharge?

Gulf of Mexico

What is the name of the three highlands that stretched from the Gulf of Mexico to the Arctic Ocean?

I'm not sure.

The lower Mississippi and some of the Ohio basin are what type of region?

I'm not sure.

Originally trees covered all of what?

I'm not sure.

What Highland stop at the national boundary?

I'm not sure.

The Ohio River discharges where?

I'm not sure.


Due to its large size and wide range of geographic features, the United States contains examples of nearly every global climate. The climate is temperate in most areas, subtropical in the Southern United States, tropical in Hawaii and southern Florida, polar in Alaska, semiarid in the Great Plains west of the 100th meridian, Mediterranean in coastal California and arid in the Great Basin. Its comparatively favorable agricultural climate contributed (in part) to the country's rise as a world power, with infrequent severe drought in the major agricultural regions, a general lack of widespread flooding, and a mainly temperate climate that receives adequate precipitation.

What is the climate like in the Southern United States?

subtropical

Hawaii has what type of climate?

tropical

Which state is known for its Mediterranean climate?

California

What contributed to the rise of the US as a world power?

agricultural climate

What is the climate like in most areas of the US?

temperate

The southwestern part of what country is subtropical

I'm not sure.

Hawaii and what other state or subtropical?

I'm not sure.

The Great Plains are erred west of what Meridian?

I'm not sure.

The United States favorable agricultural climate hindered what?

I'm not sure.

The United States has frequent droughts and widespread what?

I'm not sure.


The Great Basin and Columbia Plateau (the Intermontane Plateaus) are arid or semiarid regions that lie in the rain shadow of the Cascades and Sierra Nevada. Precipitation averages less than 15 inches (38 cm). The Southwest is a hot desert, with temperatures exceeding 100 °F (37.8 °C) for several weeks at a time in summer. The Southwest and the Great Basin are also affected by the monsoon from the Gulf of California from July to September, which brings localized but often severe thunderstorms to the region.

Which areas have arid regions?

The Great Basin and Columbia Plateau

What is the precipitation average in the Intermontane plateaus?

15 inches

In the southwest, how high do temperatures get?

100 °F (37.8 °C)

During which months are portions of the US affected by the monsoon from the Gulf of California?

July to September

What type of weather do monsoons bring?

severe thunderstorms

The great basin and what other region are semiarid?

I'm not sure.

The cascade Sierra Nevada receive how much precipitation on average

I'm not sure.

South-central United States is a hot desert with temperatures exceeding what?

I'm not sure.

The Southeast and great basin are affected by what?

I'm not sure.

Monsoons bring widespread what to the region?

I'm not sure.


Much of California consists of a Mediterranean climate, with sometimes excessive rainfall from October–April and nearly no rain the rest of the year. In the Pacific Northwest rain falls year-round, but is much heavier during winter and spring. The mountains of the west receive abundant precipitation and very heavy snowfall. The Cascades are one of the snowiest places in the world, with some places averaging over 600 inches (1,524 cm) of snow annually, but the lower elevations closer to the coast receive very little snow.

What is the most prevalent type of climate nCalifornia?

Mediterranean

During what time of the year does California receive the most rainfall?

October–April

Which region of the US experiences rain year round?

Pacific Northwest

Which region in the US is also one of the most snowiest places in the world?

The Cascades

How many inches of snow do regions of the Cascades receive?

600 inches

California has little rainfall and what type of climate?

I'm not sure.

California receives the least amount of rainfall during what months?

I'm not sure.

The what mountains receive little precipitation and light snowfall?

I'm not sure.

What mountain range averages under 600 inches of snow year?

I'm not sure.


On average, the mountains of the western states receive the highest levels of snowfall on Earth. The greatest annual snowfall level is at Mount Rainier in Washington, at 692 inches (1,758 cm); the record there was 1,122 inches (2,850 cm) in the winter of 1971–72. This record was broken by the Mt. Baker Ski Area in northwestern Washington which reported 1,140 inches (2,896 cm) of snowfall for the 1998-99 snowfall season. Other places with significant snowfall outside the Cascade Range are the Wasatch Mountains, near the Great Salt Lake, the San Juan Mountains in Colorado, and the Sierra Nevada, near Lake Tahoe.

Which mountainous region receives the highest snowfall on Earth?

mountains of the western states

Which mountain in Washington receives the most amount of snowfall?

Mount Rainier

What is the record amount of snowfall at Mount Rainer?

1,122 inches

In what year did Mount Rainer receive a record amount of snowfall?

The Sierra Nevadas are located near which lake?

Lake Tahoe

On average the mountains of the Western states receive the lowest levels of what?

I'm not sure.

The lowest annual snowfall level is on what mountain?

I'm not sure.

Mount Baker had the highest recorded snowfall and how many inches?

I'm not sure.

In what year did Mount Baker receive the highest recorded snowfall?

I'm not sure.

Other places significant snowfall in the cascade Range or what?

I'm not sure.


In the east, while snowfall does not approach western levels, the region near the Great Lakes and the mountains of the Northeast receive the most. Along the northwestern Pacific coast, rainfall is greater than anywhere else in the continental U.S., with Quinault Rainforest in Washington having an average of 137 inches (348 cm). Hawaii receives even more, with 460 inches (1,168 cm) measured annually on Mount Waialeale, in Kauai. The Mojave Desert, in the southwest, is home to the driest locale in the U.S. Yuma, Arizona, has an average of 2.63 inches (6.7 cm) of precipitation each year.

Which regions in the East receives the most amount of snowfall?

Great Lakes and the mountains of the Northeast

Which region of the US receives the most amount of rainfall?

northwestern Pacific coast

What is the average amount of rainfall that the Quinault rainforest in Washington receives?

137 inches

Which state receives an average of 460 inches of rainfall per year?

Hawaii

What is the name of the desert that is located in the driest region in the US?

Mojave Desert

Which region of the East receives the least amount of snowfall?

I'm not sure.

Which region of the US receives the least amount of rainfall

I'm not sure.

Was named the rain force in Oregon?

I'm not sure.

What state receives an average of 400 inches of rainfall per year?

I'm not sure.

What is the name of the joys desert in the world?

I'm not sure.


In central portions of the U.S., tornadoes are more common than anywhere else on Earth and touch down most commonly in the spring and summer. Deadly and destructive hurricanes occur almost every year along the Atlantic seaboard and the Gulf of Mexico. The Appalachian region and the Midwest experience the worst floods, though virtually no area in the U.S. is immune to flooding. The Southwest has the worst droughts; one is thought to have lasted over 500 years and to have hurt Ancestral Pueblo peoples. The West is affected by large wildfires each year.

Where are tornadoes most common on Earth?

central portions of the U.S.

During which seasons are tornados most common?

spring and summer

Which regions experience the worst flooding in the US?

Appalachian region and the Midwest

Which region experiences the worst droughts in the US?

Southwest

What type of disasters affects the western US every year?

wildfires

Where tornadoes least common on earth?

I'm not sure.

What are most common in the summer and fall?

I'm not sure.

Destructive hurricanes occur along the West Coast and where else?

I'm not sure.

The Northwest and what other region experienced the worst flooding in the US?

I'm not sure.

What disaster affects the Southwest every year?

I'm not sure.


Occasional severe flooding is experienced. There was the Great Mississippi Flood of 1927, the Great Flood of 1993, and widespread flooding and mudslides caused by the 1982-1983 El Niño event in the western United States. Localized flooding can, however, occur anywhere, and mudslides from heavy rain can cause problems in any mountainous area, particularly the Southwest. Large stretches of desert shrub in the west can fuel the spread of wildfires. The narrow canyons of many mountain areas in the west and severe thunderstorm activity during the summer lead to sometimes devastating flash floods as well, while Nor'Easter snowstorms can bring activity to a halt throughout the Northeast (although heavy snowstorms can occur almost anywhere).

The Great Mississippi occurred during what year?

What fuels wildfires and causes them to spread in the west?

desert shrub

What type of storms can cause most activity to stop?

Nor'Easter snowstorms

What is the name of the event that caused major flooding in the western US?

El Niño

What is the name of the major event that caused flooding in the eastern United States?

I'm not sure.

The Mississippi did not flood during what year?

I'm not sure.

The narrow canyons of many mounds can lead to what?

I'm not sure.

What type of storms occur all over the East Coast?

I'm not sure.


The West Coast of the continental United States and areas of Alaska (including the Aleutian Islands, the Alaskan Peninsula and southern Alaskan coast) make up part of the Pacific Ring of Fire, an area of heavy tectonic and volcanic activity that is the source of 90% of the world's earthquakes.[citation needed] The American Northwest sees the highest concentration of active volcanoes in the United States, in Washington, Oregon and northern California along the Cascade Mountains. There are several active volcanoes located in the islands of Hawaii, including Kilauea in ongoing eruption since 1983, but they do not typically adversely affect the inhabitants of the islands. There has not been a major life-threatening eruption on the Hawaiian islands since the 17th century. Volcanic eruptions can occasionally be devastating, such as in the 1980 eruption of Mount St. Helens in Washington.

What is the area in the pacific known for heavy volcanic activity?

Pacific Ring of Fire

The Pacific Ring of Fire contains what percentage of the earthquakes on Earth?

Which Hawaiin volcano has been erupting since 1983?

Kilauea

When was the last time that the Hawaiin islands experienced a life threatening volcanic eruption?

17th century

What year did Mt St. Helens erupt causing devastating damage?

What volcano erupted in 1990?

I'm not sure.

What is the source of 80% of the world's earthquakes?

I'm not sure.

What Hawaiian volcano has been erupting since 1985?

I'm not sure.

When was the first time the Hawaiian Islands experienced a life-threatening volcanic eruption?

I'm not sure.

The American Southwest sees the highest concentration of what?

I'm not sure.


Compact Disc (CD) is a digital optical disc data storage format. The format was originally developed to store and play only sound recordings but was later adapted for storage of data (CD-ROM). Several other formats were further derived from these, including write-once audio and data storage (CD-R), rewritable media (CD-RW), Video Compact Disc (VCD), Super Video Compact Disc (SVCD), Photo CD, PictureCD, CD-i, and Enhanced Music CD. Audio CDs and audio CD players have been commercially available since October 1982.

When did Audio CDs become available for purchase?

What does CD stand for?

Compact Disc

What were CD's originally created to store?

sound recordings

What does SVCD stand for?

Super Video Compact Disc

In what year were compact discs realesed for purchase?

What was the original intended format for CDs?

data storage

What year were CDs changed so that they could store data?

I'm not sure.

What does ROM in CD-ROM stand for?

I'm not sure.

Which was released first; CD-R or CD-RW?

I'm not sure.

Who created the CD?

I'm not sure.

What does CD-i stand for?

I'm not sure.


In 2004, worldwide sales of audio CDs, CD-ROMs and CD-Rs reached about 30 billion discs. By 2007, 200 billion CDs had been sold worldwide. CDs are increasingly being replaced by other forms of digital storage and distribution, with the result that audio CD sales rates in the U.S. have dropped about 50% from their peak; however, they remain one of the primary distribution methods for the music industry. In 2014, revenues from digital music services matched those from physical format sales for the first time.

In what year were digital and physical music sales the same?

How many CDs had been distrubuted worldwide by 2007?

200 billion

What percent decrease did audio CD sales experience?

How many CDs had been distrubuted around the world by 2007?

200 billion

In 2004 how many CDs had been sold around the world?

30 billion

What year did digital media begin to replace CDs?

I'm not sure.

How many CDs had been sold in the US by 2007?

I'm not sure.

In what year did CD sales peak?

I'm not sure.

Why are CD sales doing better than digital storage services?

I'm not sure.

How have CD sales changed internationally?

I'm not sure.


The Compact Disc is an evolution of LaserDisc technology, where a focused laser beam is used that enables the high information density required for high-quality digital audio signals. Prototypes were developed by Philips and Sony independently in the late 1970s. In 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. After a year of experimentation and discussion, the Red Book CD-DA standard was published in 1980. After their commercial release in 1982, compact discs and their players were extremely popular. Despite costing up to $1,000, over 400,000 CD players were sold in the United States between 1983 and 1984. The success of the compact disc has been credited to the cooperation between Philips and Sony, who came together to agree upon and develop compatible hardware. The unified design of the compact disc allowed consumers to purchase any disc or player from any company, and allowed the CD to dominate the at-home music market unchallenged.

Who created Compact Disc prototypes in the 1970s?

Philips and Sony

How lond did the creation of Red Book CD-DA standard take?

a year

How many CD players were sold in the United States in their first year?

What did the CD evolve from?

LaserDisc

What made it possible for CDs to be played on any companies CD player?

unified design

To what does the compact disc owe its prosperity?

cooperation between Philips and Sony

What year did CD players become available for purchase?

Which company created the CD first?

I'm not sure.

How many CD players sold in 1984?

I'm not sure.

What year was the LaserDisc created?

I'm not sure.

How long was the Red Book CD-DA in print?

I'm not sure.

How were customers disadvantaged by the Philips and Sony merger?

I'm not sure.


In 1974, L. Ottens, director of the audio division of Philips, started a small group with the aim to develop an analog optical audio disc with a diameter of 20 cm and a sound quality superior to that of the vinyl record. However, due to the unsatisfactory performance of the analog format, two Philips research engineers recommended a digital format in March 1974. In 1977, Philips then established a laboratory with the mission of creating a digital audio disc. The diameter of Philips's prototype compact disc was set at 11.5 cm, the diagonal of an audio cassette.

In what year did Philips institute a laboratory to create a digital audio disc?

What was the proposed diameter for the original compact disc?

11.5 cm

What year did Philips propse the idea of a digital audio format?

Who was the director of the Philips audio division in 1974?

L. Ottens

What Philips engineer recommended a digital format?

I'm not sure.

What was the 20cm diameter based on?

I'm not sure.

What year was the digital audio disc released?

I'm not sure.

How many engineer recommended the 11.5 cm diameter?

I'm not sure.

Who was the director of Philips by 1977?

I'm not sure.


Heitaro Nakajima, who developed an early digital audio recorder within Japan's national public broadcasting organization NHK in 1970, became general manager of Sony's audio department in 1971. His team developed a digital PCM adaptor audio tape recorder using a Betamax video recorder in 1973. After this, in 1974 the leap to storing digital audio on an optical disc was easily made. Sony first publicly demonstrated an optical digital audio disc in September 1976. A year later, in September 1977, Sony showed the press a 30 cm disc that could play 60 minutes of digital audio (44,100 Hz sampling rate and 16-bit resolution) using MFM modulation. In September 1978, the company demonstrated an optical digital audio disc with a 150-minute playing time, 44,056 Hz sampling rate, 16-bit linear resolution, and cross-interleaved error correction code—specifications similar to those later settled upon for the standard Compact Disc format in 1980. Technical details of Sony's digital audio disc were presented during the 62nd AES Convention, held on 13–16 March 1979, in Brussels. Sony's AES technical paper was published on 1 March 1979. A week later, on 8 March, Philips publicly demonstrated a prototype of an optical digital audio disc at a press conference called "Philips Introduce Compact Disc" in Eindhoven, Netherlands.

Where was the 62nd AES Convention held?

Brussels

Who was the general manger of Sony's audio department in 1971?

Heitaro Nakajima

What year did Sony first exhibit the use of an optical digital audio disc?

Where was the Philips Introduce Compact disc conference held?

Eindhoven, Netherlands

What did Nakajima's team use to create a digital PCM adaptor audio tape recorder?

Betamax video recorder

When did Sony release it's AES technical paper?

1 March 1979

What Japanese city is NHK located in?

I'm not sure.

Who was Sony's general manager in 1970?

I'm not sure.

When was the Betamax video recorder created?

I'm not sure.

How many minutes could Sony's 1976 optical digital disk play?

I'm not sure.

What was the sampling rate of Philips' 1979 optical digital dic?

I'm not sure.


As a result, in 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. Led by engineers Kees Schouhamer Immink and Toshitada Doi, the research pushed forward laser and optical disc technology. After a year of experimentation and discussion, the task force produced the Red Book CD-DA standard. First published in 1980, the standard was formally adopted by the IEC as an international standard in 1987, with various amendments becoming part of the standard in 1996.

In what year did Sony and Philips band together to design a new digital audio disc?

What year was the Red Book CD-DA standard released?

When did the IEC isntigate the Red Book CD-DA as an international standard?

Who headed the 1979 Sony and Philips digital audio disc task force?

Kees Schouhamer Immink and Toshitada Doi

Which company did Kees Schouhamer Immink work for?

I'm not sure.

What did the team create five years after joining?

I'm not sure.

What does IEC stand for?

I'm not sure.

Who wrote the amendments in 1996?

I'm not sure.

What did CD-DA stand for?

I'm not sure.


The Japanese launch was followed in March 1983 by the introduction of CD players and discs to Europe and North America (where CBS Records released sixteen titles). This event is often seen as the "Big Bang" of the digital audio revolution. The new audio disc was enthusiastically received, especially in the early-adopting classical music and audiophile communities, and its handling quality received particular praise. As the price of players gradually came down, and with the introduction of the portable Walkman the CD began to gain popularity in the larger popular and rock music markets. The first artist to sell a million copies on CD was Dire Straits, with their 1985 album Brothers in Arms. The first major artist to have his entire catalogue converted to CD was David Bowie, whose 15 studio albums were made available by RCA Records in February 1985, along with four greatest hits albums. In 1988, 400 million CDs were manufactured by 50 pressing plants around the world.

Who first sold a million copies on CD?

Dire Straits

Which artist was the first to have their full catalogue converted to CD?

David Bowie

What year was the Dire Straits album Brothers in Arms released?

How many CDs were mass produced in 1988?

400 million

How many studio albums did David Bowie release in February 1985?


The CD was planned to be the successor of the gramophone record for playing music, rather than primarily as a data storage medium. From its origins as a musical format, CDs have grown to encompass other applications. In 1983, following the CD's introduction, Immink and Braat presented the first experiments with erasable compact discs during the 73rd AES Convention. In June 1985, the computer-readable CD-ROM (read-only memory) and, in 1990, CD-Recordable were introduced, also developed by both Sony and Philips. Recordable CDs were a new alternative to tape for recording music and copying music albums without defects introduced in compression used in other digital recording methods. Other newer video formats such as DVD and Blu-ray use the same physical geometry as CD, and most DVD and Blu-ray players are backward compatible with audio CD.

What does ROM stand for?

read-only memory

What year did Sony and Philips release CD-Recordable?

What year was the 73rd AES Convention?

What was the CDs predecessor?

gramophone record

When was the gramophone released?

I'm not sure.

What was the problem with recordable CDs?

I'm not sure.

When was the DVD first released?

I'm not sure.

Who created the DVD and Blu-ray discs?

I'm not sure.

Who created the gramophone?

I'm not sure.


Meanwhile, with the advent and popularity of Internet-based distribution of files in lossily-compressed audio formats such as MP3, sales of CDs began to decline in the 2000s. For example, between 2000 - 2008, despite overall growth in music sales and one anomalous year of increase, major-label CD sales declined overall by 20%, although independent and DIY music sales may be tracking better according to figures released 30 March 2009, and CDs still continue to sell greatly. As of 2012, CDs and DVDs made up only 34 percent of music sales in the United States. In Japan, however, over 80 percent of music was bought on CDs and other physical formats as of 2015.

What portion of music sales did CDs and DVDs account for in the United States as of 2012?

34 percent

Which country attributes over 80 percent of its music sales to physical formats?

Japan

How are MP3s compressed?

lossily-compressed

When did CD sales experience their original decline?

What has caused a decrease in CD sales?

Internet-based distribution of files

In what year did CDs have an unusual spike in sales?

I'm not sure.

What percentage of music sales do MP3s make up?

I'm not sure.

How are CDs compressed?

I'm not sure.

By what percentage have DIY and independent CDs increased?

I'm not sure.

When did MP3 sales take off in Japan?

I'm not sure.


Replicated CDs are mass-produced initially using a hydraulic press. Small granules of heated raw polycarbonate plastic are fed into the press. A screw forces the liquefied plastic into the mold cavity. The mold closes with a metal stamper in contact with the disc surface. The plastic is allowed to cool and harden. Once opened, the disc substrate is removed from the mold by a robotic arm, and a 15 mm diameter center hole (called a stacking ring) is created. The time it takes to "stamp" one CD is usually two to three seconds.

How are CDs mass produced?

hydraulic press

What type of material is used to make CDs?

raw polycarbonate plastic

What size is the diameter of the center hole in a CD?

15 mm

How long does it take to stamp out one CD?

two to three seconds

What is the term for the center hole in a CD?

stacking ring

How large is the screw that forces the plastic into the cavity?

I'm not sure.

How long does it take the plastic to cool?

I'm not sure.

What is the robotic arm called?

I'm not sure.

What is a hydraulic press made out of?

I'm not sure.

What closes the mold?

I'm not sure.


This method produces the clear plastic blank part of the disc. After a metallic reflecting layer (usually aluminium, but sometimes gold or other metal) is applied to the clear blank substrate, the disc goes under a UV light for curing and it is ready to go to press. To prepare to press a CD, a glass master is made, using a high-powered laser on a device similar to a CD writer. The glass master is a positive image of the desired CD surface (with the desired microscopic pits and lands). After testing, it is used to make a die by pressing it against a metal disc.

What materials can be used to make the reflective layer on a CD?

usually aluminium, but sometimes gold or other metal

What type of light is used to cure CDs?

UV

What is a glass master?

positive image of the desired CD surface

How are glass masters created?

high-powered laser

What is the clear blank side made out of?

I'm not sure.

What is used to apply the reflecting layer to the clear layer?

I'm not sure.

How is a CD writer made?

I'm not sure.

How is a positive image made of the CD made?

I'm not sure.

How are the pits and lands made?

I'm not sure.


The die is a negative image of the glass master: typically, several are made, depending on the number of pressing mills that are to make the CD. The die then goes into a press, and the physical image is transferred to the blank CD, leaving a final positive image on the disc. A small amount of lacquer is applied as a ring around the center of the disc, and rapid spinning spreads it evenly over the surface. Edge protection lacquer is applied before the disc is finished. The disc can then be printed and packed.

What is the term for a negative image of the glass master?

die

How is the positive image on a CD protected?

lacquer

How is lacquer distrubted on a CD?

rapid spinning

What is the name of the positive image?

I'm not sure.

What is liquid is applied to the blank CD?

I'm not sure.

How much edge protection lacquer is needed for the finished disc?

I'm not sure.

How is the physical image placed on the blank CD?

I'm not sure.


The most expensive part of a CD is the jewel case. In 1995, material costs were 30 cents for the jewel case and 10 to 15 cents for the CD. Wholesale cost of CDs was $0.75 to $1.15, which retailed for $16.98. On average, the store received 35 percent of the retail price, the record company 27 percent, the artist 16 percent, the manufacturer 13 percent, and the distributor 9 percent. When 8-track tapes, cassette tapes, and CDs were introduced, each was marketed at a higher price than the format they succeeded, even though the cost to produce the media was reduced. This was done because the apparent value increased. This continued from vinyl to CDs but was broken when Apple marketed MP3s for $0.99, and albums for $9.99. The incremental cost, though, to produce an MP3 is very small.

What is the priciest component of a CD?

jewel case

Why did the cost of audio music increase when the production costs decreased?

value increased

What did CDs retail for in 1995?

Who received the most profit from the sale of CDs?

the store

How much did a jewel case cost in 1995?

30 cents

Why were successive formats less expensive than their predecessors?

I'm not sure.

When did Apple place MP3s on the market?

I'm not sure.

What was the wholesale cost of a cassette tape?

I'm not sure.

What was the most expensive part of an MP3?

I'm not sure.

What percentage of an MP3 does Apple receive?

I'm not sure.


CD-R recordings are designed to be permanent. Over time, the dye's physical characteristics may change causing read errors and data loss until the reading device cannot recover with error correction methods. The design life is from 20 to 100 years, depending on the quality of the discs, the quality of the writing drive, and storage conditions. However, testing has demonstrated such degradation of some discs in as little as 18 months under normal storage conditions. This failure is known as disc rot, for which there are several, mostly environmental, reasons.

How long are CDs expected to last?

20 to 100 years

What can cause sudden disc degradation?

disc rot

Are CDs meant for permanent or temporary use?

permanent

What can the aluminium on a disc cause reading errors?

I'm not sure.

Why does disc rot allow CD-Rs to last for years?

I'm not sure.

Why are CD-Rs considered temporary?

I'm not sure.

What company discovered disc rot?

I'm not sure.

What type of environment is best for a CD-R?

I'm not sure.


The ReWritable Audio CD is designed to be used in a consumer audio CD recorder, which will not (without modification) accept standard CD-RW discs. These consumer audio CD recorders use the Serial Copy Management System (SCMS), an early form of digital rights management (DRM), to conform to the United States' Audio Home Recording Act (AHRA). The ReWritable Audio CD is typically somewhat more expensive than CD-RW due to (a) lower volume and (b) a 3% AHRA royalty used to compensate the music industry for the making of a copy.

What does SCMS stand for?

Serial Copy Management System

What does DRM stand for?

digital rights management

What does AHRA stand for?

Audio Home Recording Act

What type of CD is intended to be used in a Consumer audio CD Recorder?

ReWritable Audio CD

Which is less expensive, the ReWritable Audio CD or a CD-RW?

CD-RW

What plays standard CD-RW discs without changes?

I'm not sure.

What royalties does a CD-RW have?

I'm not sure.

What year was the digital rights management published?

I'm not sure.

What is the international standard for home recordings?

I'm not sure.

Why is the CD-RW more expensive than the ReWritable CD?

I'm not sure.


Due to technical limitations, the original ReWritable CD could be written no faster than 4x speed. High Speed ReWritable CD has a different design, which permits writing at speeds ranging from 4x to 12x. Original CD-RW drives can only write to original ReWritable CDs. High Speed CD-RW drives can typically write to both original ReWritable CDs and High Speed ReWritable CDs. Both types of CD-RW discs can be read in most CD drives. Higher speed CD-RW discs, Ultra Speed (16x to 24x write speed) and Ultra Speed+ (32x write speed) are now available.

How fast could the first ReWritable CD be written?

4x speed

Which CD has writing speeds betwen 4x and 12x?

High Speed ReWritable CD

How fast can Ultra Speed+ CDs write?

How fast can Ultra Speed CDs write?

16x to 24x

What has only a 1x write speed?

I'm not sure.

Which type of CD-RW cannot be read on a CD drive?

I'm not sure.

Does a High Speed CD-RW drive write faster on ReWriteable CDs or High Speed ReWritable CDs?

I'm not sure.

Which ReWriteable CD is most common?

I'm not sure.

Why was the original ReWriteable CD written only at speeds faster than 4x?

I'm not sure.


A CD is read by focusing a 780 nm wavelength (near infrared) semiconductor laser housed within the CD player, through the bottom of the polycarbonate layer. The change in height between pits and lands results in a difference in the way the light is reflected. By measuring the intensity change with a photodiode, the data can be read from the disc. In order to accommodate the spiral pattern of data, the semiconductor laser is placed on a swing arm within the disc tray of any CD player. This swing arm allows the laser to read information from the centre to the edge of a disc, without having to interrupt the spinning of the disc itself.

Where is the semiconductor laser found in a CD player?

on a swing arm

What wavelenght is used to pull data from a CD?

780 nm

In what pattern is data stored on a CD?

spiral

What is used to discern the change of intensity in light on a CD?

photodiode

What createds the change in light reflected off of a CD?

change in height between pits and lands

How long is the swing arm?

I'm not sure.

How many layers of polycarbonate are there?

I'm not sure.

Why is the data arranged in a spiral pattern?

I'm not sure.

Where is the photodiode?

I'm not sure.

What does the width of a pit indicate?

I'm not sure.


The pits and lands themselves do not directly represent the zeros and ones of binary data. Instead, non-return-to-zero, inverted encoding is used: a change from pit to land or land to pit indicates a one, while no change indicates a series of zeros. There must be at least two and no more than ten zeros between each one, which is defined by the length of the pit. This in turn is decoded by reversing the eight-to-fourteen modulation used in mastering the disc, and then reversing the cross-interleaved Reed–Solomon coding, finally revealing the raw data stored on the disc. These encoding techniques (defined in the Red Book) were originally designed for CD Digital Audio, but they later became a standard for almost all CD formats (such as CD-ROM).

What type of encoding do CDs implement?

non-return-to-zero

Where can one find the encoding techniques for CDs?

Red Book

What type of result from a CD will return a one?

change from pit to land or land to pit

What type of modulation is implemented when a disc is mastered?

eight-to-fourteen

How many ones are there between each zero?

I'm not sure.

What decodes the eight-to-fourteen modulation?

I'm not sure.

What is Reed-Solomon coding?

I'm not sure.

Who designed the CD Digital Audio coding techniques?

I'm not sure.

What does a land represent?

I'm not sure.


CDs are susceptible to damage during handling and from environmental exposure. Pits are much closer to the label side of a disc, enabling defects and contaminants on the clear side to be out of focus during playback. Consequently, CDs are more likely to suffer damage on the label side of the disc. Scratches on the clear side can be repaired by refilling them with similar refractive plastic or by careful polishing. The edges of CDs are sometimes incompletely sealed, allowing gases and liquids to corrode the metal reflective layer and to interfere with the focus of the laser on the pits. The fungus Geotrichum candidum, found in Belize, has been found to consume the polycarbonate plastic and aluminium found in CDs.

Where can one expect to find damage on a disc?

label side of the disc

How are scratches on a CD fixed?

refilling them with similar refractive plastic or by careful polishing

What eats at the plastic and aluminum found in CDs?

fungus Geotrichum candidum

Where does the fungus Geotrichum candidum originate from?

Belize

Where is polycarbonate plastic created?

I'm not sure.

What are lands closer to?

I'm not sure.

How are scratches on the labeled side of a disc fixed?

I'm not sure.

What causes edges of CDs to be incorrectly sealed?

I'm not sure.

Where is the metal reflective layer located?

I'm not sure.


The digital data on a CD begins at the center of the disc and proceeds toward the edge, which allows adaptation to the different size formats available. Standard CDs are available in two sizes. By far, the most common is 120 millimetres (4.7 in) in diameter, with a 74- or 80-minute audio capacity and a 650 or 700 MiB (737,280,000-byte) data capacity. This capacity was reportedly specified by Sony executive Norio Ohga in May 1980 so as to be able to contain the entirety of the London Philharmonic Orchestra's recording of Beethoven's Ninth Symphony on one disc. This is a myth according to Kees Immink, as the code format had not yet been decided in May 1980. The adoption of EFM one month later would have allowed a playing time of 97 minutes for 120 mm diameter or 74 minutes for a disc as small as 100 mm. The 120 mm diameter has been adopted by subsequent formats, including Super Audio CD, DVD, HD DVD, and Blu-ray Disc. Eighty-millimeter discs ("Mini CDs") were originally designed for CD singles and can hold up to 24 minutes of music or 210 MiB of data but never became popular.[citation needed] Today, nearly every single is released on a 120 mm CD, called a Maxi single.[citation needed]

Where is the start of data on a CD?

the center

What size CD is most frequently used?

120 millimetres (4.7 in)

What is the size of a Mini CD?

Eighty-millimeter

What is the size of a Maxi Single?

120 mm

Who was the Sony Executive in 1980?

Norio Ohga

Who named the Maxi single?

I'm not sure.

How many minutes does a Super Audio CD hold?

I'm not sure.

When were Mini-CDs released?

I'm not sure.

Why are CDs limited to one size?

I'm not sure.

When was the London Philharmonic Orchestra's recording of the Ninth Symphony created?

I'm not sure.


The logical format of an audio CD (officially Compact Disc Digital Audio or CD-DA) is described in a document produced in 1980 by the format's joint creators, Sony and Philips. The document is known colloquially as the Red Book CD-DA after the colour of its cover. The format is a two-channel 16-bit PCM encoding at a 44.1 kHz sampling rate per channel. Four-channel sound was to be an allowable option within the Red Book format, but has never been implemented. Monaural audio has no existing standard on a Red Book CD; thus, mono source material is usually presented as two identical channels in a standard Red Book stereo track (i.e., mirrored mono); an MP3 CD, however, can have audio file formats with mono sound.

Where does the Red Book get it's name from?

the colour of its cover

What is the formal name for a CD?

Compact Disc Digital Audio

Do CDs have a two or four channel format?

two-channel

What format has never been implemented on CDs?

Four-channel sound

What was the sampling rate for the four-channel sound?

I'm not sure.

When was four-channel sound implemented?

I'm not sure.

What is the Red Book format for monaural audio?

I'm not sure.

What is the official name of the Red Book?

I'm not sure.

What is the PCM for an MP3 mono sound chanel?

I'm not sure.


Compact Disc + Graphics is a special audio compact disc that contains graphics data in addition to the audio data on the disc. The disc can be played on a regular audio CD player, but when played on a special CD+G player, it can output a graphics signal (typically, the CD+G player is hooked up to a television set or a computer monitor); these graphics are almost exclusively used to display lyrics on a television set for karaoke performers to sing along with. The CD+G format takes advantage of the channels R through W. These six bits store the graphics information.

What is the primary use of Compact Disc + Graphics?

to display lyrics on a television set for karaoke

How is graphics information read from a CD+ Graphics?

television set or a computer monitor

Which channels does the CD+G use to hold graphics data?

channels R through W

Why can a CD+G not play on an audio CD player?

I'm not sure.

How many bits does a normal CD use?

I'm not sure.

Why are CD-G players not useful for karaoke?

I'm not sure.

What channels does a normal CD use?

I'm not sure.


SVCD has two-thirds the resolution of DVD, and over 2.7 times the resolution of VCD. One CD-R disc can hold up to 60 minutes of standard quality SVCD-format video. While no specific limit on SVCD video length is mandated by the specification, one must lower the video bit rate, and therefore quality, to accommodate very long videos. It is usually difficult to fit much more than 100 minutes of video onto one SVCD without incurring significant quality loss, and many hardware players are unable to play video with an instantaneous bit rate lower than 300 to 600 kilobits per second.

How much video can a CD-R contain?

60 minutes

Which has better resolution, a VCD or SVCD?

SVCD

How are lengthy videos fit onto SVCDs?

lower the video bit rate

What is the maximum amount of video a SVCD can properly hold?

100 minutes

How much can a VCD hold?

I'm not sure.

Why is there a video length limit on SVCD?

I'm not sure.

What is the kilobit rate for a DVD?

I'm not sure.

How does a VCN compare to a DVD?

I'm not sure.

Why is it difficult to put more than 60 minutes on a DVD?

I'm not sure.


Photo CD is a system designed by Kodak for digitizing and storing photos on a CD. Launched in 1992, the discs were designed to hold nearly 100 high-quality images, scanned prints and slides using special proprietary encoding. Photo CDs are defined in the Beige Book and conform to the CD-ROM XA and CD-i Bridge specifications as well. They are intended to play on CD-i players, Photo CD players and any computer with the suitable software irrespective of the operating system. The images can also be printed out on photographic paper with a special Kodak machine. This format is not to be confused with Kodak Picture CD, which is a consumer product in CD-ROM format.

Who created Photo CDs?

Kodak

When were Photo CDs initially released?

How many images could Photo CDs initially contain?

What type of paper can Photo CD images be produced on?

photographic paper

In what book are Photo CD standards defined?

Beige Book

When was the Beige Book published?

I'm not sure.

How many photos does the CD-ROM XA hold?

I'm not sure.

Who invented CD-i Players?

I'm not sure.

Why can't Photo CDs work on any computer?

I'm not sure.

When was the Kodak Picture CD released?

I'm not sure.


The Red Book audio specification, except for a simple "anti-copy" statement in the subcode, does not include any copy protection mechanism. Known at least as early as 2001, attempts were made by record companies to market "copy-protected" non-standard compact discs, which cannot be ripped, or copied, to hard drives or easily converted to MP3s. One major drawback to these copy-protected discs is that most will not play on either computer CD-ROM drives or some standalone CD players that use CD-ROM mechanisms. Philips has stated that such discs are not permitted to bear the trademarked Compact Disc Digital Audio logo because they violate the Red Book specifications. Numerous copy-protection systems have been countered by readily available, often free, software.

When did record companies first attempt to protect their CDs from copying?

Who said that protected CDs are not allowed to carry the CDDA logo?

Philips

Where does the Red Book mention copy protection?

in the subcode

When was the "anti-copy" subcode written in the Red Book?

I'm not sure.

Who created the anti-protection systems software?

I'm not sure.

When was the Compact Disc Digital Audio logo copyrighted?

I'm not sure.

What devices do standard CDs not play on?

I'm not sure.

Why does Philips want non-standard discs to have the trademarked logo?

I'm not sure.


A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Today, some transistors are packaged individually, but many more are found embedded in integrated circuits.

What is the use of a transistor?

to amplify or switch electronic signals and electrical power

What is a transistor made of?

semiconductor material

What is the minimum amount of external connection terminals to call an item a transistor?

three

Why does a transistor increase a signal?

the controlled (output) power can be higher than the controlling (input) power

Where are most transistors found?

embedded in integrated circuits

What is an integrated circuit used for?

I'm not sure.

Where are most semiconductor devices found?

I'm not sure.

What are integrated circuits made of?

I'm not sure.

How many transistors are embedded in most integrated circuits?

I'm not sure.

What controls how strong a signal is?

I'm not sure.


The transistor is the fundamental building block of modern electronic devices, and is ubiquitous in modern electronic systems. First conceived by Julius Lilienfeld in 1926 and practically implemented in 1947 by American physicists John Bardeen, Walter Brattain, and William Shockley, the transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things. The transistor is on the list of IEEE milestones in electronics, and Bardeen, Brattain, and Shockley shared the 1956 Nobel Prize in Physics for their achievement.

When was the first transistor created?

Who invented the first transistor?

Julius Lilienfeld

When was the first transistor implemented for practical use?

When did the implementers receive a Nobel Prize for making the transistor?

What list is the transistor on?

list of IEEE milestones in electronics

When were smaller, cheaper radios introduced?

I'm not sure.

What besides the transistor is on the IEEE list of milestones in electronics?

I'm not sure.

What did Julius Lilienfeld receive for inventing the transistor?

I'm not sure.

Who was the first person to use transistors in calculators?

I'm not sure.

Why were transistors in 1947 easier to practically implement than transistors in 1926?

I'm not sure.


The thermionic triode, a vacuum tube invented in 1907, enabled amplified radio technology and long-distance telephony. The triode, however, was a fragile device that consumed a lot of power. Physicist Julius Edgar Lilienfeld filed a patent for a field-effect transistor (FET) in Canada in 1925, which was intended to be a solid-state replacement for the triode. Lilienfeld also filed identical patents in the United States in 1926 and 1928. However, Lilienfeld did not publish any research articles about his devices nor did his patents cite any specific examples of a working prototype. Because the production of high-quality semiconductor materials was still decades away, Lilienfeld's solid-state amplifier ideas would not have found practical use in the 1920s and 1930s, even if such a device had been built. In 1934, German inventor Oskar Heil patented a similar device.

When was the thermionic triode invented?

What was the purpose of the thermionic triode?

amplified radio technology and long-distance telephony

Who filed a patent for the field-effect transistor?

Physicist Julius Edgar Lilienfeld

Where did Lilienfeld file his patent?

Canada

What year did Lilienfeld file his patent?

Where did Oskar Heil file a patent?

I'm not sure.

How long would it take for a practical field-effect transistor be built?

I'm not sure.

Why did Oskar Heil invent a device similar to Lilienfeld's?

I'm not sure.

Why were field-effect transistors not practical without high quality semiconductor materials?

I'm not sure.

Where was the thermionic triode invented?

I'm not sure.


From November 17, 1947 to December 23, 1947, John Bardeen and Walter Brattain at AT&T's Bell Labs in the United States performed experiments and observed that when two gold point contacts were applied to a crystal of germanium, a signal was produced with the output power greater than the input. Solid State Physics Group leader William Shockley saw the potential in this, and over the next few months worked to greatly expand the knowledge of semiconductors. The term transistor was coined by John R. Pierce as a contraction of the term transresistance. According to Lillian Hoddeson and Vicki Daitch, authors of a biography of John Bardeen, Shockley had proposed that Bell Labs' first patent for a transistor should be based on the field-effect and that he be named as the inventor. Having unearthed Lilienfeld’s patents that went into obscurity years earlier, lawyers at Bell Labs advised against Shockley's proposal because the idea of a field-effect transistor that used an electric field as a "grid" was not new. Instead, what Bardeen, Brattain, and Shockley invented in 1947 was the first point-contact transistor. In acknowledgement of this accomplishment, Shockley, Bardeen, and Brattain were jointly awarded the 1956 Nobel Prize in Physics "for their researches on semiconductors and their discovery of the transistor effect."

At what time did Bardeen and Brattain experiment on increasing signal output?

November 17, 1947 to December 23, 1947

What were gold contacts attached to to increase signal output?

germanium

Who was the Solid State Physics Group Leader?

William Shockley

Who came up with the term transistor?

John R. Pierce

Why was the term transistor used?

a contraction of the term transresistance

When did lawyers at Bell Labs find Lilienfeld's patents?

I'm not sure.

Who thought of the term semiconductor?

I'm not sure.

How many patents did Lilienfeld file?

I'm not sure.

When was the term transistor first used?

I'm not sure.

Where was the biography of John Bardeen written?

I'm not sure.


In 1948, the point-contact transistor was independently invented by German physicists Herbert Mataré and Heinrich Welker while working at the Compagnie des Freins et Signaux, a Westinghouse subsidiary located in Paris. Mataré had previous experience in developing crystal rectifiers from silicon and germanium in the German radar effort during World War II. Using this knowledge, he began researching the phenomenon of "interference" in 1947. By June 1948, witnessing currents flowing through point-contacts, Mataré produced consistent results using samples of germanium produced by Welker, similar to what Bardeen and Brattain had accomplished earlier in December 1947. Realizing that Bell Labs' scientists had already invented the transistor before them, the company rushed to get its "transistron" into production for amplified use in France's telephone network.

In what year was the point-contact transistor invented?

Who invented the point-contact transistor?

Herbert Mataré and Heinrich Welker

Where were Matare and Welker working when inventing the point-contact transistor?

Compagnie des Freins et Signaux

What was the name of Matare and Welker's transistor?

transistron

What was the transistron used for?

amplified use in France's telephone network

What were Matare and Welker's transistors made of?

I'm not sure.

When did Heinrich Welker start researching electronics?

I'm not sure.

When did Matare and Welker realize that Bell Labs had invented a transistor?

I'm not sure.

Where were the "transistrons" produced?

I'm not sure.

Who was in charge of France's telephone network?

I'm not sure.


Although several companies each produce over a billion individually packaged (known as discrete) transistors every year, the vast majority of transistors are now produced in integrated circuits (often shortened to IC, microchips or simply chips), along with diodes, resistors, capacitors and other electronic components, to produce complete electronic circuits. A logic gate consists of up to about twenty transistors whereas an advanced microprocessor, as of 2009, can use as many as 3 billion transistors (MOSFETs). "About 60 million transistors were built in 2002… for [each] man, woman, and child on Earth."

How many transistors make up a logic gate?

up to about twenty transistors

How many transistors make up a microprocessor?

as many as 3 billion transistors

How many transistors were made in 2002?

60 million transistors were built in 2002… for [each] man, woman, and child

How many individually packaged transistors are produced each year?

over a billion

What are some abbreviations for integrated circuits?

IC, microchips or simply chips

How many integrated circuits are produced every year?

I'm not sure.

How many men, women, and children are on Earth?

I'm not sure.

How many logic gates are in a microchip?

I'm not sure.

What produces electronic components?

I'm not sure.

Where are transistors being produced?

I'm not sure.


The essential usefulness of a transistor comes from its ability to use a small signal applied between one pair of its terminals to control a much larger signal at another pair of terminals. This property is called gain. It can produce a stronger output signal, a voltage or current, which is proportional to a weaker input signal; that is, it can act as an amplifier. Alternatively, the transistor can be used to turn current on or off in a circuit as an electrically controlled switch, where the amount of current is determined by other circuit elements.

Why is a transistor so useful?

gain

What is gain?

it can act as an amplifier

What is an additional use of the transistor?

turn current on or off in a circuit

What determines the amount of current in an electrically controlled switch?

other circuit elements

What controls how strong the output signal is?

I'm not sure.

Where are transistors located?

I'm not sure.

How large is a transistor in comparison to a terminal?

I'm not sure.

What does a signal become when the transistor does not work properly?

I'm not sure.

Where would an electrically controlled switch be located?

I'm not sure.


There are two types of transistors, which have slight differences in how they are used in a circuit. A bipolar transistor has terminals labeled base, collector, and emitter. A small current at the base terminal (that is, flowing between the base and the emitter) can control or switch a much larger current between the collector and emitter terminals. For a field-effect transistor, the terminals are labeled gate, source, and drain, and a voltage at the gate can control a current between source and drain.

How many types of transistors are there?

two

What are the components of a bipolar transistor?

base, collector, and emitter

What controls the large current between the collector and emitter?

A small current at the base terminal

What are the components of a field-effect transistor?

gate, source, and drain

In a field-effect transistor, what controls the current between the source and drain?

a voltage at the gate

Why would someone use a bipolar transistor instead of a field-effect transistor?

I'm not sure.

What is the most common kind of transistor?

I'm not sure.

What controls the voltage at the gate of a field-effect transistor?

I'm not sure.

Where is the collector terminal located?

I'm not sure.

Where is the gate terminal located?

I'm not sure.


In a grounded-emitter transistor circuit, such as the light-switch circuit shown, as the base voltage rises, the emitter and collector currents rise exponentially. The collector voltage drops because of reduced resistance from collector to emitter. If the voltage difference between the collector and emitter were zero (or near zero), the collector current would be limited only by the load resistance (light bulb) and the supply voltage. This is called saturation because current is flowing from collector to emitter freely. When saturated, the switch is said to be on.

Why does the collector voltage drop in grounded-emitter transistor circuits?

reduced resistance from collector to emitter

What would happen if the voltage difference from collector and emitter were zero?

the collector current would be limited only by the load resistance (light bulb) and the supply voltage

What is the term for a zero difference between collector and emitter?

saturation

Why is the term saturation named as such?

current is flowing from collector to emitter freely

What position is the switch in when saturated?

on

What causes reduced resistance from collector to emitter?

I'm not sure.

Why does "current" have that name?

I'm not sure.

What changes the most in a grounded-emitter transistor circuit?

I'm not sure.

What is the load resistance in a light bulb?

I'm not sure.

What changes the amount of supply voltage?

I'm not sure.


Providing sufficient base drive current is a key problem in the use of bipolar transistors as switches. The transistor provides current gain, allowing a relatively large current in the collector to be switched by a much smaller current into the base terminal. The ratio of these currents varies depending on the type of transistor, and even for a particular type, varies depending on the collector current. In the example light-switch circuit shown, the resistor is chosen to provide enough base current to ensure the transistor will be saturated.

What is a major problem with using bipolar transistors as switches?

Providing sufficient base drive current

What does the transistor provide?

current gain

What determines the current ratio in transistors?

the type of transistor

If the type of transistor is the same what determines the current ratio?

collector current

What controls how much gain a transistor provides?

I'm not sure.

How much current is needed to saturate a light-switch?

I'm not sure.

What determines how much collector current there is?

I'm not sure.

What fluctuates the most in a transistor?

I'm not sure.