QUES: Leakage is equivalent to a resistor in parallel with the capacitor. Constant exposure to heat can cause dielectric breakdown and excessive leakage, a problem often seen in older vacuum tube circuits, particularly where oiled paper and foil capacitors were used. In many vacuum tube circuits, interstage coupling capacitors are used to conduct a varying signal from the plate of one tube to the grid circuit of the next stage. A leaky capacitor can cause the grid circuit voltage to be raised from its normal bias setting, causing excessive current or signal distortion in the downstream tube. In power amplifiers this can cause the plates to glow red, or current limiting resistors to overheat, even fail. Similar considerations apply to component fabricated solid-state (transistor) amplifiers, but owing to lower heat production and the use of modern polyester dielectric barriers this once-common problem has become relatively rare.
What type of capacitor can cause signal distortion in the downstream tube?

ANS: A leaky capacitor

QUES: The Taiping Rebellion in the mid-19th century was the first major instance of anti-Manchu sentiment threatening the stability of the dynasty. Hong Xiuquan, a failed civil service candidate, led the Taiping Rebellion, amid widespread social unrest and worsening famine. In 1851 Hong Xiuquan and others launched an uprising in Guizhou province, established the Taiping Heavenly Kingdom with Hong himself as king, claiming he often had visions of God and that he was the brother of Jesus Christ. Slavery, concubinage, arranged marriage, opium smoking, footbinding, judicial torture, and the worship of idols were all banned. However, success and subsequent authority and power led to internal feuds, defections and corruption. In addition, British and French troops, equipped with modern weapons, had come to the assistance of the Qing imperial army. It was not until 1864 that Qing armies under Zeng Guofan succeeded in crushing the revolt. The rebellion not only posed the most serious threat towards Qing rulers; it was also "bloodiest civil war of all time." Between 20 and 30 million people died during its fourteen-year course from 1850 to 1864. After the outbreak of this rebellion, there were also revolts by the Muslims and Miao people of China against the Qing dynasty, most notably in the Dungan Revolt (186277) in the northwest and the Panthay Rebellion (18561873) in Yunnan.
Who led the Rebellion?

ANS: Hong Xiuquan

QUES: The university culture developed differently in northern Europe than it did in the south, although the northern (primarily Germany, France and Great Britain) and southern universities (primarily Italy) did have many elements in common. Latin was the language of the university, used for all texts, lectures, disputations and examinations. Professors lectured on the books of Aristotle for logic, natural philosophy, and metaphysics; while Hippocrates, Galen, and Avicenna were used for medicine. Outside of these commonalities, great differences separated north and south, primarily in subject matter. Italian universities focused on law and medicine, while the northern universities focused on the arts and theology. There were distinct differences in the quality of instruction in these areas which were congruent with their focus, so scholars would travel north or south based on their interests and means. There was also a difference in the types of degrees awarded at these universities. English, French and German universities usually awarded bachelor's degrees, with the exception of degrees in theology, for which the doctorate was more common. Italian universities awarded primarily doctorates. The distinction can be attributed to the intent of the degree holder after graduation in the north the focus tended to be on acquiring teaching positions, while in the south students often went on to professional positions. The structure of northern universities tended to be modeled after the system of faculty governance developed at the University of Paris. Southern universities tended to be patterned after the student-controlled model begun at the University of Bologna. Among the southern universities, a further distinction has been noted between those of northern Italy, which followed the pattern of Bologna as a "self-regulating, independent corporation of scholars" and those of southern Italy and Iberia, which were "founded by royal and imperial charter to serve the needs of government."
What type of subjects did the universities of northern Europe focus on?

ANS: arts and theology

QUES: Aposematism, where organisms are brightly colored as a warning to predators, is the antithesis of camouflage. Some organisms pose a threat to their predatorsfor example they may be poisonous, or able to harm them physically. Aposematic coloring involves bright, easily recognizable and unique colors and patterns. For example, bright coloration in Variable Checkerspot butterflies leads to decreased predation attempts by avian predators. Upon being harmed (e.g., stung) by their prey, the appearance in such an organism will be remembered as something to avoid. While that particular prey organism may be killed, the coloring benefits the prey species as a whole.
What do predators use to warn their prey?

ANS:
unanswerable