QUES: Since the armature windings of a direct-current or universal motor are moving through a magnetic field, they have a voltage induced in them. This voltage tends to oppose the motor supply voltage and so is called "back electromotive force (emf)". The voltage is proportional to the running speed of the motor. The back emf of the motor, plus the voltage drop across the winding internal resistance and brushes, must equal the voltage at the brushes. This provides the fundamental mechanism of speed regulation in a DC motor. If the mechanical load increases, the motor slows down; a lower back emf results, and more current is drawn from the supply. This increased current provides the additional torque to balance the new load.

Voltage opposing the motor supply voltage is called what?
What is the answer?
ANS: back electromotive force
QUES: In the early part of the 20th century, San Diego hosted two World's Fairs: the Panama-California Exposition in 1915 and the California Pacific International Exposition in 1935. Both expositions were held in Balboa Park, and many of the Spanish/Baroque-style buildings that were built for those expositions remain to this day as central features of the park. The buildings were intended to be temporary structures, but most remained in continuous use until they progressively fell into disrepair. Most were eventually rebuilt, using castings of the original facades to retain the architectural style. The menagerie of exotic animals featured at the 1915 exposition provided the basis for the San Diego Zoo. During the 1950s there was a citywide festival called Fiesta del Pacifico highlighting the area's Spanish and Mexican past. In the 2010s there was a proposal for a large-scale celebration of the 100th anniversary of Balboa Park, but the plans were abandoned when the organization tasked with putting on the celebration went out of business.

Where did many of the San Diego Zoo's exotic animals come from?
What is the answer?
ANS: Panama-California Exposition in 1915
QUES: A text is self-referential when it speaks about itself and makes reference to itself. According to Stefan Wild, the Quran demonstrates this metatextuality by explaining, classifying, interpreting and justifying the words to be transmitted. Self-referentiality is evident in those passages where the Quran refers to itself as revelation (tanzil), remembrance (dhikr), news (naba'), criterion (furqan) in a self-designating manner (explicitly asserting its Divinity, "And this is a blessed Remembrance that We have sent down; so are you now denying it?"), or in the frequent appearance of the "Say" tags, when Muhammad is commanded to speak (e.g., "Say: 'God's guidance is the true guidance' ", "Say: 'Would you then dispute with us concerning God?' "). According to Wild the Quran is highly self-referential. The feature is more evident in early Meccan suras.

Which term that the Quran uses for itself doesn't mean "news"?
What is the answer?
ANS:
unanswerable