romikgosai/squad_modified huggingface dataset:
Throughout the war, the King and Queen provided morale-boosting visits throughout the United Kingdom, visiting bomb sites, munitions factories, and troops. The King visited military forces abroad in France in December 1939, North Africa and Malta in June 1943, Normandy in June 1944, southern Italy in July 1944, and the Low Countries in October 1944. Their high public profile and apparently indefatigable determination secured their place as symbols of national resistance. At a social function in 1944, Chief of the Imperial General Staff Sir Alan Brooke, revealed that every time he met Field Marshal Bernard Montgomery he thought he was after his job. The King replied: "You should worry, when I meet him, I always think he's after mine!"

Questions and answers:
['
Q: What country did the King and Queen visit in July 1944?
A: Italy', '
Q: When did the King and Queen visit North Africa and Malta?
A: June 1943', '
Q: What improved when the King and Queen visited different military sites?
A: morale']
George VI's reign saw the acceleration of the dissolution of the British Empire. The Statute of Westminster 1931 had already acknowledged the evolution of the Dominions into separate sovereign states. The process of transformation from an empire to a voluntary association of independent states, known as the Commonwealth, gathered pace after the Second World War. During the ministry of Clement Attlee, British India became the two independent dominions of India and Pakistan in 1947. George relinquished the title of Emperor of India, and became King of India and King of Pakistan instead. In 1950 he ceased to be King of India when it became a republic within the Commonwealth of Nations, but he remained King of Pakistan until his death and India recognised his new title of Head of the Commonwealth. Other countries left the Commonwealth, such as Burma in January 1948, Palestine (divided between Israel and the Arab states) in May 1948 and the Republic of Ireland in 1949.

Questions and answers:
['
Q: What is the association of independent states in Britain called?
A: the Commonwealth', '
Q: What two dominions did British India become?
A: India and Pakistan', '
Q: What country left the Commonwealth in January 1948?
A: Burma', '
Q: What year was the Republic of Ireland formed?
A: 1949']
In 1947, the King and his family toured Southern Africa. The Prime Minister of the Union of South Africa, Jan Smuts, was facing an election and hoped to make political capital out of the visit. George was appalled, however, when instructed by the South African government to shake hands only with whites, and referred to his South African bodyguards as "the Gestapo". Despite the tour, Smuts lost the election the following year, and the new government instituted a strict policy of racial segregation.

Questions and answers:
['
Q: Who was the Prime Minister of South Africa in 1947?
A: Jan Smuts', "
Q: What were the King's South African bodyguards referred as? 
A: the Gestapo", '
Q: Who instructed the King to only shake hands with whites in South Africa?
A: South African government']
The stress of the war had taken its toll on the King's health, exacerbated by his heavy smoking and subsequent development of lung cancer among other ailments, including arteriosclerosis and thromboangiitis obliterans. A planned tour of Australia and New Zealand was postponed after the King suffered an arterial blockage in his right leg, which threatened the loss of the leg and was treated with a right lumbar sympathectomy in March 1949. His elder daughter Elizabeth, the heir presumptive, took on more royal duties as her father's health deteriorated. The delayed tour was re-organised, with Elizabeth and her husband, the Duke of Edinburgh, taking the place of the King and Queen. The King was well enough to open the Festival of Britain in May 1951, but on 23 September 1951, his left lung was removed by Clement Price Thomas after a malignant tumour was found. In October 1951, Princess Elizabeth and the Duke of Edinburgh went on a month-long tour of Canada; the trip had been delayed for a week due to the King's illness. At the State Opening of Parliament in November, the King's speech from the throne was read for him by the Lord Chancellor, Lord Simonds. His Christmas broadcast of 1951 was recorded in sections, and then edited together.

Questions and answers:
['
Q: What kind of cancer did the King develop?
A: lung cancer', "
Q: What developed in the King's right leg that prevented him from touring Australia?
A: arterial blockage", "
Q: What treatment helped prevent the loss of the King's right leg?
A: right lumbar sympathectomy", "
Q: Who was the King's heir presumptive?
A: Elizabeth", "
Q: Who was Elizabeth's spouse?
A: Duke of Edinburgh"]
From 9 February for two days his coffin rested in St. Mary Magdalene Church, Sandringham, before lying in state at Westminster Hall from 11 February. His funeral took place at St. George's Chapel, Windsor Castle, on the 15th. He was interred initially in the Royal Vault until he was transferred to the King George VI Memorial Chapel inside St. George's on 26 March 1969. In 2002, fifty years after his death, the remains of his widow, Queen Elizabeth The Queen Mother, and the ashes of his younger daughter Princess Margaret, who both died that year, were interred in the chapel alongside him.

Questions and answers:
["
Q: What church did the King's funeral take place on the 15th?
A: Windsor Castle", '
Q: What year did Queen Elizabeth die?
A: 2002', '
Q: What year did Princess Margaret die?
A: 2002', "
Q: In which chapel does King George's body lie in today? 
A: King George VI Memorial Chapel"]
In the words of Labour Member of Parliament George Hardie, the abdication crisis of 1936 did "more for republicanism than fifty years of propaganda". George VI wrote to his brother Edward that in the aftermath of the abdication he had reluctantly assumed "a rocking throne", and tried "to make it steady again". He became king at a point when public faith in the monarchy was at a low ebb. During his reign his people endured the hardships of war, and imperial power was eroded. However, as a dutiful family man and by showing personal courage, he succeeded in restoring the popularity of the monarchy.

Questions and answers:
['
Q: How high was public faith in the monarchy when King George assumed the throne?
A: low', '
Q: What position did George Hardie hold?
A: Labour Member of Parliament', "
Q: Who was George VI's brother?
A: Edward"]
Found in applications as diverse as industrial fans, blowers and pumps, machine tools, household appliances, power tools, and disk drives, electric motors can be powered by direct current (DC) sources, such as from batteries, motor vehicles or rectifiers, or by alternating current (AC) sources, such as from the power grid, inverters or generators. Small motors may be found in electric watches. General-purpose motors with highly standardized dimensions and characteristics provide convenient mechanical power for industrial use. The largest of electric motors are used for ship propulsion, pipeline compression and pumped-storage applications with ratings reaching 100 megawatts. Electric motors may be classified by electric power source type, internal construction, application, type of motion output, and so on.

Questions and answers:
['
Q: What is the largest rating of an electric motor?
A: 100 megawatts', '
Q: What is the main example of a DC power source?
A: batteries', '
Q: What does AC stand for?
A: alternating current', '
Q: What does DC stand for?
A: direct current', '
Q: In what device are small motors commonly found?
A: electric watches']
Perhaps the first electric motors were simple electrostatic devices created by the Scottish monk Andrew Gordon in the 1740s. The theoretical principle behind production of mechanical force by the interactions of an electric current and a magnetic field, Ampère's force law, was discovered later by André-Marie Ampère in 1820. The conversion of electrical energy into mechanical energy by electromagnetic means was demonstrated by the British scientist Michael Faraday in 1821. A free-hanging wire was dipped into a pool of mercury, on which a permanent magnet (PM) was placed. When a current was passed through the wire, the wire rotated around the magnet, showing that the current gave rise to a close circular magnetic field around the wire. This motor is often demonstrated in physics experiments, brine substituting for toxic mercury. Though Barlow's wheel was an early refinement to this Faraday demonstration, these and similar homopolar motors were to remain unsuited to practical application until late in the century.

Questions and answers:
['
Q: Who created the first electrostatic device?
A: Andrew Gordon', '
Q: Who discovered the principles of magnetic and electric interactions?
A: André-Marie Ampère', '
Q: In what year did Faraday convert electrical energy into mechanical energy?
A: 1821', '
Q: What toxic substance originally served the function of brine in primitive motors?
A: mercury']
In 1827, Hungarian physicist Ányos Jedlik started experimenting with electromagnetic coils. After Jedlik solved the technical problems of the continuous rotation with the invention of the commutator, he called his early devices "electromagnetic self-rotors". Although they were used only for instructional purposes, in 1828 Jedlik demonstrated the first device to contain the three main components of practical DC motors: the stator, rotor and commutator. The device employed no permanent magnets, as the magnetic fields of both the stationary and revolving components were produced solely by the currents flowing through their windings.

Questions and answers:
['
Q: In what year did Jedlik begin experimenting with electromagnetism?
A: 1827', '
Q: Besides the stator and the communicator, what is an element of a DC motor?
A: rotor', '
Q: What did Jedlik call his earliest devices?
A: electromagnetic self-rotors', '
Q: What discovery solved the problem of continuous rotation?
A: commutator', "
Q: What did Jedlik's improved device eliminate the need for?
A: permanent magnets"]
After many other more or less successful attempts with relatively weak rotating and reciprocating apparatus the Prussian Moritz von Jacobi created the first real rotating electric motor in May 1834 that actually developed a remarkable mechanical output power. His motor set a world record which was improved only four years later in September 1838 by Jacobi himself. His second motor was powerful enough to drive a boat with 14 people across a wide river. It was not until 1839/40 that other developers worldwide managed to build motors of similar and later also of higher performance.

Questions and answers:
['
Q: When were developers competing with Jacobi able to match his accomplishments?
A: 1839/40', "
Q: What was Jacobi's improved motor used to propel?
A: boat", '
Q: Who created the first real electric motor?
A: Moritz von Jacobi', "
Q: Who broke the world record set by Jacobi's first motor?
A: Jacobi himself", "
Q: How long did it take for Jacobi's first world record to be broken?
A: four years"]
The first commutator DC electric motor capable of turning machinery was invented by the British scientist William Sturgeon in 1832. Following Sturgeon's work, a commutator-type direct-current electric motor made with the intention of commercial use was built by the American inventor Thomas Davenport, which he patented in 1837. The motors ran at up to 600 revolutions per minute, and powered machine tools and a printing press. Due to the high cost of primary battery power, the motors were commercially unsuccessful and Davenport went bankrupt. Several inventors followed Sturgeon in the development of DC motors but all encountered the same battery power cost issues. No electricity distribution had been developed at the time. Like Sturgeon's motor, there was no practical commercial market for these motors.

Questions and answers:
['
Q: Who developed the first mnotor capable of being used for machinery?
A: William Sturgeon', '
Q: Which inventor went bankrupt?
A: Thomas Davenport', '
Q: What was the main problem with applying early electric motors to industry?
A: the high cost of primary battery power', '
Q: What necessary technical development had yet to occur to make electric motors useful?
A: electricity distribution', "
Q: How fast did Sturgeon and Davenport's motors run?
A: 600 revolutions per minute"]
A major turning point in the development of DC machines took place in 1864, when Antonio Pacinotti described for the first time the ring armature with its symmetrically grouped coils closed upon themselves and connected to the bars of a commutator, the brushes of which delivered practically non-fluctuating current. The first commercially successful DC motors followed the invention by Zénobe Gramme who, in 1871, reinvented Pacinotti's design. In 1873, Gramme showed that his dynamo could be used as a motor, which he demonstrated to great effect at exhibitions in Vienna and Philadelphia by connecting two such DC motors at a distance of up to 2 km away from each other, one as a generator. (See also 1873 : l'expérience décisive [Decisive Workaround] .)

Questions and answers:
["
Q: What made Pacinotti's motor an important advancement?
A: non-fluctuating current", '
Q: Who created a motor similar to Pacinotti?
A: Zénobe Gramme', "
Q: How far from each other were the motors in Gramme's demonstrations?
A: 2 km", '
Q: Besides a motor, what did Gramme use the other device for?
A: generator', '
Q: In what two cities did Gramme conduct his demonstrations?
A: Vienna and Philadelphia']
In 1886, Frank Julian Sprague invented the first practical DC motor, a non-sparking motor that maintained relatively constant speed under variable loads. Other Sprague electric inventions about this time greatly improved grid electric distribution (prior work done while employed by Thomas Edison), allowed power from electric motors to be returned to the electric grid, provided for electric distribution to trolleys via overhead wires and the trolley pole, and provided controls systems for electric operations. This allowed Sprague to use electric motors to invent the first electric trolley system in 1887–88 in Richmond VA, the electric elevator and control system in 1892, and the electric subway with independently powered centrally controlled cars, which were first installed in 1892 in Chicago by the South Side Elevated Railway where it became popularly known as the "L". Sprague's motor and related inventions led to an explosion of interest and use in electric motors for industry, while almost simultaneously another great inventor was developing its primary competitor, which would become much more widespread. The development of electric motors of acceptable efficiency was delayed for several decades by failure to recognize the extreme importance of a relatively small air gap between rotor and stator. Efficient designs have a comparatively small air gap. [a] The St. Louis motor, long used in classrooms to illustrate motor principles, is extremely inefficient for the same reason, as well as appearing nothing like a modern motor.

Questions and answers:
['
Q: What needs to exist between the rotor and stator for increased efficiency?
A: small air gap', '
Q: Which inventor created the first useful DC motor?
A: Frank Julian Sprague', "
Q: What was the transportation advancement made possible by Sprague's designs?
A: electric trolley system", "
Q: What was the name of Chicago's first electric trolley system?
A: South Side Elevated Railway", '
Q: Who did Sprague work for early in his career?
A: Thomas Edison']
Application of electric motors revolutionized industry. Industrial processes were no longer limited by power transmission using line shafts, belts, compressed air or hydraulic pressure. Instead every machine could be equipped with its own electric motor, providing easy control at the point of use, and improving power transmission efficiency. Electric motors applied in agriculture eliminated human and animal muscle power from such tasks as handling grain or pumping water. Household uses of electric motors reduced heavy labor in the home and made higher standards of convenience, comfort and safety possible. Today, electric motors stand for more than half of the electric energy consumption in the US.

Questions and answers:
['
Q: How much energy do electric motors use in the modern United States?
A: more than half', '
Q: In what domain did electric motors reduce reliance on humans and animals?
A: agriculture', '
Q: Besides shafts, belts and compressed air, what did electric motors reduce the need for?
A: hydraulic pressure', '
Q: Where did electric motors improve convenience and safety?
A: in the home']
A commutator is a mechanism used to switch the input of most DC machines and certain AC machines consisting of slip ring segments insulated from each other and from the electric motor's shaft. The motor's armature current is supplied through the stationary brushes in contact with the revolving commutator, which causes required current reversal and applies power to the machine in an optimal manner as the rotor rotates from pole to pole. In absence of such current reversal, the motor would brake to a stop. In light of significant advances in the past few decades due to improved technologies in electronic controller, sensorless control, induction motor, and permanent magnet motor fields, electromechanically commutated motors are increasingly being displaced by externally commutated induction and permanent-magnet motors.

Questions and answers:
['
Q: What would a rotor do without current reversal?
A: brake to a stop', '
Q: What switches the input of most DC motors?
A: commutator', '
Q: From where is current to the motor supplied?
A: stationary brushes', '
Q: What two motor types are ascendant today?
A: externally commutated induction and permanent-magnet']
A commutated DC motor has a set of rotating windings wound on an armature mounted on a rotating shaft. The shaft also carries the commutator, a long-lasting rotary electrical switch that periodically reverses the flow of current in the rotor windings as the shaft rotates. Thus, every brushed DC motor has AC flowing through its rotating windings. Current flows through one or more pairs of brushes that bear on the commutator; the brushes connect an external source of electric power to the rotating armature.

Questions and answers:
['
Q: What does the communicator do?
A: reverses the flow of current in the rotor windings', '
Q: What type of current is featured in brushed DC motors?
A: AC', '
Q: Where do brushes get their power?
A: external', '
Q: What is the main feature of the shaft in a commutated DC motor?
A: rotating']
The rotating armature consists of one or more coils of wire wound around a laminated, magnetically "soft" ferromagnetic core. Current from the brushes flows through the commutator and one winding of the armature, making it a temporary magnet (an electromagnet). The magnetic field produced by the armature interacts with a stationary magnetic field produced by either PMs or another winding a field coil, as part of the motor frame. The force between the two magnetic fields tends to rotate the motor shaft. The commutator switches power to the coils as the rotor turns, keeping the magnetic poles of the rotor from ever fully aligning with the magnetic poles of the stator field, so that the rotor never stops (like a compass needle does), but rather keeps rotating as long as power is applied.

Questions and answers:
['
Q: Current flowing to create a temporary magent is called what?
A: electromagnet', '
Q: What rotates the motor shaft?
A: force between the two magnetic fields', '
Q: What element of the motor keeps the poles from alligning?
A: commutator', '
Q: What non-motor device demonstrates why a commutator is needed?
A: compass']
Many of the limitations of the classic commutator DC motor are due to the need for brushes to press against the commutator. This creates friction. Sparks are created by the brushes making and breaking circuits through the rotor coils as the brushes cross the insulating gaps between commutator sections. Depending on the commutator design, this may include the brushes shorting together adjacent sections – and hence coil ends – momentarily while crossing the gaps. Furthermore, the inductance of the rotor coils causes the voltage across each to rise when its circuit is opened, increasing the sparking of the brushes. This sparking limits the maximum speed of the machine, as too-rapid sparking will overheat, erode, or even melt the commutator. The current density per unit area of the brushes, in combination with their resistivity, limits the output of the motor. The making and breaking of electric contact also generates electrical noise; sparking generates RFI. Brushes eventually wear out and require replacement, and the commutator itself is subject to wear and maintenance (on larger motors) or replacement (on small motors). The commutator assembly on a large motor is a costly element, requiring precision assembly of many parts. On small motors, the commutator is usually permanently integrated into the rotor, so replacing it usually requires replacing the whole rotor.

Questions and answers:
['
Q: How is RFI generated?
A: sparking', '
Q: What do brushes need to be in contact with?
A: commutator', '
Q: What is created by contact between parts of the motor?
A: friction', '
Q: What does sparking limit?
A: maximum speed', '
Q: What motor components most need replacement and maintenance? 
A: Brushes']
Large brushes are desired for a larger brush contact area to maximize motor output, but small brushes are desired for low mass to maximize the speed at which the motor can run without the brushes excessively bouncing and sparking. (Small brushes are also desirable for lower cost.) Stiffer brush springs can also be used to make brushes of a given mass work at a higher speed, but at the cost of greater friction losses (lower efficiency) and accelerated brush and commutator wear. Therefore, DC motor brush design entails a trade-off between output power, speed, and efficiency/wear.

Questions and answers:
['
Q: What are large brushes favorable for?
A: motor output', '
Q: Whate are small brushes favorable for?
A: speed', '
Q: What type of brushes are cheapest?
A: small', '
Q: How can the speed of larger brushes be increased?
A: Stiffer brush springs', '
Q: Besides wear, what is a downside of stiff brush springs?
A: lower efficiency']
A PM motor does not have a field winding on the stator frame, instead relying on PMs to provide the magnetic field against which the rotor field interacts to produce torque. Compensating windings in series with the armature may be used on large motors to improve commutation under load. Because this field is fixed, it cannot be adjusted for speed control. PM fields (stators) are convenient in miniature motors to eliminate the power consumption of the field winding. Most larger DC motors are of the "dynamo" type, which have stator windings. Historically, PMs could not be made to retain high flux if they were disassembled; field windings were more practical to obtain the needed amount of flux. However, large PMs are costly, as well as dangerous and difficult to assemble; this favors wound fields for large machines.

Questions and answers:
['
Q: What can a PM motor not be adjusted for?
A: speed control', '
Q: What is another name for PM fields?
A: stators', '
Q: What design feature does a PM motor lack?
A: field winding', '
Q: What do field windings provide?
A: flux']