romikgosai/squad_modified huggingface dataset:
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.

Questions and answers:
['
Q: Where is the semiconductor laser found in a CD player?
A: on a swing arm', '
Q: What wavelenght is used to pull data from a CD?
A: 780 nm', '
Q: What is used to discern the change of intensity in light on a CD?
A: photodiode', '
Q: In what pattern is data stored on a CD?
A: spiral', '
Q: What createds the change in light reflected off of a CD?
A: change in height between pits and lands']
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).

Questions and answers:
['
Q: What type of result from a CD will return a one?
A: change from pit to land or land to pit', '
Q: Where can one find the encoding techniques for CDs?
A: Red Book', '
Q: What type of encoding do CDs implement?
A: non-return-to-zero', '
Q: What type of modulation is implemented when a disc is mastered?
A: eight-to-fourteen']
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.

Questions and answers:
['
Q: Where can one expect to find damage on a disc?
A: label side of the disc', '
Q: How are scratches on a CD fixed?
A: refilling them with similar refractive plastic or by careful polishing', '
Q: What eats at the plastic and aluminum found in CDs?
A: fungus Geotrichum candidum', '
Q: Where does the fungus Geotrichum candidum originate from?
A: Belize']
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]

Questions and answers:
['
Q: Where is the start of data on a CD?
A: the center', '
Q: What size CD is most frequently used?
A: 120 millimetres (4.7 in)', '
Q: What is the size of a Mini CD?
A: Eighty-millimeter', '
Q: What is the size of a Maxi Single?
A: 120 mm', '
Q: Who was the Sony Executive in 1980?
A: Norio Ohga']
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.

Questions and answers:
["
Q: Where does the Red Book get it's name from?
A: the colour of its cover", '
Q: What is the formal name for a CD? 
A: Compact Disc Digital Audio', '
Q: Do CDs have a two or four channel format?
A: two-channel', '
Q: What format has never been implemented on CDs?
A: Four-channel sound']
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.

Questions and answers:
['
Q: How is graphics information read from a CD+ Graphics?
A: television set or a computer monitor', '
Q: What is the primary use of Compact Disc + Graphics?
A: to display lyrics on a television set for karaoke', '
Q: Which channels does the CD+G use to hold graphics data?
A: channels R through W']
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.

Questions and answers:
['
Q: How much video can a CD-R contain?
A: 60 minutes', '
Q: Which has better resolution, a VCD or SVCD?
A: SVCD', '
Q: How are lengthy videos fit onto SVCDs?
A: lower the video bit rate', '
Q: What is the maximum amount of video a SVCD can properly hold?
A: 100 minutes']
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.

Questions and answers:
['
Q: How many images could Photo CDs initially contain?
A: 100', '
Q: When were Photo CDs initially released?
A: 1992', '
Q: Who created Photo CDs?
A: Kodak', '
Q: What type of paper can Photo CD images be produced on?
A: photographic paper', '
Q: In what book are Photo CD standards defined?
A: Beige Book']
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.

Questions and answers:
['
Q: When did record companies first attempt to protect their CDs from copying?
A: 2001', '
Q: Who said that protected CDs are not allowed to carry the CDDA logo?
A: Philips', '
Q: Where does the Red Book mention copy protection?
A: in the subcode']
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.

Questions and answers:
['
Q: What is the use of a transistor?
A: to amplify or switch electronic signals and electrical power', '
Q: What is a transistor made of?
A: semiconductor material', '
Q: Why does a transistor increase a signal?
A: the controlled (output) power can be higher than the controlling (input) power', '
Q: What is the minimum amount of external connection terminals to call an item a transistor?
A: three', '
Q: Where are most transistors found?
A: embedded in integrated circuits']
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.

Questions and answers:
['
Q: When was the first transistor created?
A: 1926', '
Q: Who invented the first transistor?
A: Julius Lilienfeld', '
Q: When was the first transistor implemented for practical use?
A: 1947', '
Q: When did the implementers receive a Nobel Prize for making the transistor?
A: 1956', '
Q: What list is the transistor on?
A: list of IEEE milestones in electronics']
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.

Questions and answers:
['
Q: When was the thermionic triode invented?
A: 1907', '
Q: What was the purpose of the thermionic triode?
A: amplified radio technology and long-distance telephony', '
Q: Who filed a patent for the field-effect transistor?
A: Physicist Julius Edgar Lilienfeld', '
Q: Where did Lilienfeld file his patent?
A: Canada', '
Q: What year did Lilienfeld file his patent?
A: 1925']
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."

Questions and answers:
['
Q: At what time did Bardeen and Brattain experiment on increasing signal output?
A: November 17, 1947 to December 23, 1947', '
Q: What were gold contacts attached to to increase signal output?
A: germanium', '
Q: Who was the Solid State Physics Group Leader?
A: William Shockley', '
Q: Who came up with the term transistor?
A: John R. Pierce', '
Q: Why was the term transistor used?
A: a contraction of the term transresistance']
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.

Questions and answers:
['
Q: In what year was the point-contact transistor invented?
A: 1948', '
Q: Where were Matare and Welker working when inventing the point-contact transistor?
A: Compagnie des Freins et Signaux', '
Q: Who invented the point-contact transistor?
A: Herbert Mataré and Heinrich Welker', "
Q: What was the name of Matare and Welker's transistor?
A: transistron", "
Q: What was the transistron used for?
A: amplified use in France's telephone network"]
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."

Questions and answers:
['
Q: How many transistors make up a logic gate?
A: up to about twenty transistors', '
Q: How many transistors make up a microprocessor?
A: as many as 3 billion transistors', '
Q: How many transistors were made in 2002?
A: 60 million transistors were built in 2002… for [each] man, woman, and child', '
Q: How many individually packaged transistors are produced each year?
A: over a billion', '
Q: What are some abbreviations for integrated circuits?
A: IC, microchips or simply chips']
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.

Questions and answers:
['
Q: Why is a transistor so useful?
A: gain', '
Q: What is gain?
A: it can act as an amplifier', '
Q: What is an additional use of the transistor?
A: turn current on or off in a circuit', '
Q: What determines the amount of current in an electrically controlled switch?
A: other circuit elements']
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.

Questions and answers:
['
Q: How many types of transistors are there?
A: two', '
Q: What controls the large current between the collector and emitter?
A: A small current at the base terminal', '
Q: What are the components of a field-effect transistor?
A: gate, source, and drain', '
Q: In a field-effect transistor, what controls the current between the source and drain?
A: a voltage at the gate', '
Q: What are the components of a bipolar transistor?
A: base, collector, and emitter']
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.

Questions and answers:
['
Q: Why does the collector voltage drop in grounded-emitter transistor circuits?
A: reduced resistance from collector to emitter', '
Q: What would happen if the voltage difference from collector and emitter were zero?
A: the collector current would be limited only by the load resistance (light bulb) and the supply voltage', '
Q: What is the term for a zero difference between collector and emitter?
A: saturation', '
Q: Why is the term saturation named as such?
A: current is flowing from collector to emitter freely', '
Q: What position is the switch in when saturated?
A: on']
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.

Questions and answers:
['
Q: What is a major problem with using bipolar transistors as switches?
A: Providing sufficient base drive current', '
Q: What does the transistor provide?
A: current gain', '
Q: What determines the current ratio in transistors?
A: the type of transistor', '
Q: If the type of transistor is the same what determines the current ratio?
A: collector current']
In a switching circuit, the idea is to simulate, as near as possible, the ideal switch having the properties of open circuit when off, short circuit when on, and an instantaneous transition between the two states. Parameters are chosen such that the "off" output is limited to leakage currents too small to affect connected circuitry; the resistance of the transistor in the "on" state is too small to affect circuitry; and the transition between the two states is fast enough not to have a detrimental effect.

Questions and answers:
['
Q: How are parameters chosen in a switching circuit?
A: the "off" output is limited to leakage currents too small to affect connected circuitry', '
Q: What is a switching circuit trying to simulate when on?
A: short circuit', '
Q: What is a switching circuit trying to simulate when off?
A: open circuit', '
Q: How quickly does the change from open circuit to short circuit happen?
A: instantaneous']
Bipolar transistors are so named because they conduct by using both majority and minority carriers. The bipolar junction transistor, the first type of transistor to be mass-produced, is a combination of two junction diodes, and is formed of either a thin layer of p-type semiconductor sandwiched between two n-type semiconductors (an n–p–n transistor), or a thin layer of n-type semiconductor sandwiched between two p-type semiconductors (a p–n–p transistor). This construction produces two p–n junctions: a base–emitter junction and a base–collector junction, separated by a thin region of semiconductor known as the base region (two junction diodes wired together without sharing an intervening semiconducting region will not make a transistor).

Questions and answers:
['
Q: What gives bipolar transistors their name?
A: they conduct by using both majority and minority carriers', '
Q: What was the first mass-produced transistor?
A: bipolar junction transistor', '
Q: What is the bipolar junction transistor a combination of?
A: two junction diodes', '
Q: What is the name for a layer of p-type semiconductor set between two n-type semiconductors?
A: n–p–n transistor', '
Q: What is the name for a layer of n-type semiconductor set between two p-type semiconductors?
A: p–n–p transistor']