Problem: A synchronous electric motor is an AC motor distinguished by a rotor spinning with coils passing magnets at the same rate as the AC and resulting magnetic field which drives it. Another way of saying this is that it has zero slip under usual operating conditions. Contrast this with an induction motor, which must slip to produce torque. One type of synchronous motor is like an induction motor except the rotor is excited by a DC field. Slip rings and brushes are used to conduct current to the rotor. The rotor poles connect to each other and move at the same speed hence the name synchronous motor. Another type, for low load torque, has flats ground onto a conventional squirrel-cage rotor to create discrete poles. Yet another, such as made by Hammond for its pre-World War II clocks, and in the older Hammond organs, has no rotor windings and discrete poles. It is not self-starting. The clock requires manual starting by a small knob on the back, while the older Hammond organs had an auxiliary starting motor connected by a spring-loaded manually operated switch.
 How isn't current brought to the rotor in a synchronous motor?
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Answer: unanswerable


Problem: The Dominican friars quickly spread, including to England, where they appeared in Oxford in 1221. In the 13th century the order reached all classes of Christian society, fought heresy, schism, and paganism by word and book, and by its missions to the north of Europe, to Africa, and Asia passed beyond the frontiers of Christendom. Its schools spread throughout the entire Church; its doctors wrote monumental works in all branches of knowledge, including the extremely important Albertus Magnus and Thomas Aquinas. Its members included popes, cardinals, bishops, legates, inquisitors, confessors of princes, ambassadors, and paciarii (enforcers of the peace decreed by popes or councils). The order was appointed by Pope Gregory IX the duty to carry out the Inquisition. In his Papal Bull Ad extirpanda of 1252, Pope Innocent IV authorised the Dominicans' use of torture under prescribed circumstances.
Who appointed the Dominican Order to begin the inquisition?
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Answer: Pope Gregory IX


Problem: By 26 March, the growing refusal of soldiers to fire into the largely nonviolent protesting crowds turned into a full-scale tumult, and resulted into thousands of soldiers putting down their arms and joining the pro-democracy movement. That afternoon, Lieutenant Colonel Amadou Toumani Touré announced on the radio that he had arrested the dictatorial president, Moussa Traoré. As a consequence, opposition parties were legalized and a national congress of civil and political groups met to draft a new democratic constitution to be approved by a national referendum.
What did students lay down?
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Answer:
unanswerable