Problem: Electric motor:

A servomotor is a motor, very often sold as a complete module, which is used within a position-control or speed-control feedback control system mainly control valves, such as motor-operated control valves. Servomotors are used in applications such as machine tools, pen plotters, and other process systems. Motors intended for use in a servomechanism must have well-documented characteristics for speed, torque, and power. The speed vs. torque curve is quite important and is high ratio for a servo motor. Dynamic response characteristics such as winding inductance and rotor inertia are also important; these factors limit the overall performance of the servomechanism loop. Large, powerful, but slow-responding servo loops may use conventional AC or DC motors and drive systems with position or speed feedback on the motor. As dynamic response requirements increase, more specialized motor designs such as coreless motors are used. AC motors' superior power density and acceleration characteristics compared to that of DC motors tends to favor PM synchronous, BLDC, induction, and SRM drive applications.

What must not be well understood when applying a servo motor for use?
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A: unanswerable

Problem: The Late Jurassic spans from 163 million to 145 million years ago. The Late Jurassic featured a massive extinction of sauropods and Ichthyosaurs due to the separation of Pangaea into Laurasia and Gondwana in an extinction known as the Jurassic-Cretaceous extinction. Sea levels rose, destroying fern prairies and creating shallows in its wake. Ichthyosaurs went extinct whereas sauropods, as a whole, did not die out in the Jurassic; in fact, some species, like the Titanosaurus, lived up to the K-T extinction. The increase in sea-levels opened up the Atlantic sea way which would continue to get larger over time. The divided world would give opportunity for the diversification of new dinosaurs.
Sea levels fell during what time period that spanned from 163 million to 145 million years ago?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
By the end of the decade a distinct genre of hard rock was emerging with bands like Led Zeppelin, who mixed the music of early rock bands with a more hard-edged form of blues rock and acid rock on their first two albums Led Zeppelin (1969) and Led Zeppelin II (1969), and Deep Purple, who began as a progressive rock group but achieved their commercial breakthrough with their fourth and distinctively heavier album, In Rock (1970). Also significant was Black Sabbath's Paranoid (1970), which combined guitar riffs with dissonance and more explicit references to the occult and elements of Gothic horror. All three of these bands have been seen as pivotal in the development of heavy metal, but where metal further accentuated the intensity of the music, with bands like Judas Priest following Sabbath's lead into territory that was often "darker and more menacing", hard rock tended to continue to remain the more exuberant, good-time music.
What is one band directly influenced by Black Sabbath?
A: Judas Priest

Context and question: Wood density is determined by multiple growth and physiological factors compounded into "one fairly easily measured wood characteristic" (Elliott 1970).
Along with growth, what kind of factors determine the density of wood?
Answer: physiological

Question: The Germanic peoples during the Migrations Period came into contact with other peoples; in the case of the populations settling in the territory of modern Germany, they encountered Celts to the south, and Balts and Slavs towards the east. The Limes Germanicus was breached in AD 260. Migrating Germanic tribes commingled with the local Gallo-Roman populations in what is now Swabia and Bavaria. The arrival of the Huns in Europe resulted in Hun conquest of large parts of Eastern Europe, the Huns initially were allies of the Roman Empire who fought against Germanic tribes, but later the Huns cooperated with the Germanic tribe of the Ostrogoths, and large numbers of Germans lived within the lands of the Hunnic Empire of Attila. Attila had both Hunnic and Germanic families and prominent Germanic chiefs amongst his close entourage in Europe. The Huns living in Germanic territories in Eastern Europe adopted an East Germanic language as their lingua franca. A major part of Attila's army were Germans, during the Huns' campaign against the Roman Empire. After Attila's unexpected death the Hunnic Empire collapsed with the Huns disappearing as a people in Europe who either escaped into Asia, or otherwise blended in amongst Europeans.
Is there an answer to this question: Which Germanic tribe did the Huns cooperate with?

Answer: Ostrogoths

Question: However, Mathews' frustration with Whitehead's books did not negatively affect his interest. In fact, there were numerous philosophers and theologians at Chicago's Divinity School that perceived the importance of what Whitehead was doing without fully grasping all of the details and implications. In 1927 they invited one of America's only Whitehead experts Henry Nelson Wieman to Chicago to give a lecture explaining Whitehead's thought. Wieman's lecture was so brilliant that he was promptly hired to the faculty and taught there for twenty years, and for at least thirty years afterward Chicago's Divinity School was closely associated with Whitehead's thought.
Is there an answer to this question: Who was frustrated in Whitehead's books but still interested?

Answer:
Mathews