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An early advantage of AC is that the power-wasting resistors used in DC locomotives for speed control were not needed in an AC locomotive: multiple taps on the transformer can supply a range of voltages. Separate low-voltage transformer windings supply lighting and the motors driving auxiliary machinery. More recently, the development of very high power semiconductors has caused the classic "universal" AC/DC motor to be largely replaced with the three-phase induction motor fed by a variable frequency drive, a special inverter that varies both frequency and voltage to control motor speed. These drives can run equally well on DC or AC of any frequency, and many modern electric locomotives are designed to handle different supply voltages and frequencies to simplify cross-border operation.
What taps can provide lighting supply?
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The answer: low-voltage transformer windings

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Whitehead makes the startling observation that "life is comparatively deficient in survival value." If humans can only exist for about a hundred years, and rocks for eight hundred million, then one is forced to ask why complex organisms ever evolved in the first place; as Whitehead humorously notes, "they certainly did not appear because they were better at that game than the rocks around them." He then observes that the mark of higher forms of life is that they are actively engaged in modifying their environment, an activity which he theorizes is directed toward the three-fold goal of living, living well, and living better. In other words, Whitehead sees life as directed toward the purpose of increasing its own satisfaction. Without such a goal, he sees the rise of life as totally unintelligible.
What observation did Whitehead make about life?
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The answer: "life is comparatively deficient in survival value."

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During the tumultuous 14th century, disputes within the leadership of the Church led to the Avignon Papacy of 130578, also called the "Babylonian Captivity of the Papacy" (a reference to the Babylonian captivity of the Jews), and then to the Great Schism, lasting from 1378 to 1418, when there were two and later three rival popes, each supported by several states. Ecclesiastical officials convened at the Council of Constance in 1414, and in the following year the council deposed one of the rival popes, leaving only two claimants. Further depositions followed, and in November 1417 the council elected Martin V (pope 141731) as pope.
What is another term for the Avignon Papacy?
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The answer: Babylonian Captivity of the Papacy

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Off-grid PV systems have traditionally used rechargeable batteries to store excess electricity. With grid-tied systems, excess electricity can be sent to the transmission grid, while standard grid electricity can be used to meet shortfalls. Net metering programs give household systems a credit for any electricity they deliver to the grid. This is handled by 'rolling back' the meter whenever the home produces more electricity than it consumes. If the net electricity use is below zero, the utility then rolls over the kilowatt hour credit to the next month. Other approaches involve the use of two meters, to measure electricity consumed vs. electricity produced. This is less common due to the increased installation cost of the second meter. Most standard meters accurately measure in both directions, making a second meter unnecessary.
Where do off-grid PV systems store excess electricity?
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The answer:
rechargeable batteries