Assertion (A): When light falls at junction of p-n photodiode, its p side becomes positive and n side becomes negative. Reason (R): When a photodiode is short circuited, the current in the external circuit flows from p side to n side. p> ?->(Show Answer!)

1. Assertion (A): When light falls at junction of p-n photodiode, its p side becomes positive and n side becomes negative. Reason (R): When a photodiode is short circuited, the current in the external circuit flows from p side to n side.

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MCQ->Assertion (A): When light falls at junction of p-n photodiode, its p side becomes positive and n side becomes negative. Reason (R): When a photodiode is short circuited, the current in the external circuit flows from p side to n side.

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MCQ-> Analyse the following passage and provide appropriate answers for the follow. Popper claimed, scientific beliefs are universal in character, and have to be so if they are to serve us in explanation and prediction. For the universality of a scientific belief implies that, no matter how many instances we have found positive, there will always be an indefinite number of unexamined instances which may or may not also be positive. We have no good reason for supposing that any of these unexamined instances will be positive, or will be negative, so we must refrain from drawing any conclusions. On the other hand, a single negative instance is sufficient to prove that the belief is false, for such an instance is logically incompatible with the universal truth of the belief. Provided, therefore, that the instance is accepted as negative we must conclude that the scientific belief is false. In short, we can sometimes deduce that a universal scientific belief is false but we can never induce that a universal scientific belief is true. It is sometimes argued that this 'asymmetry' between verification and falsification is not nearly as pronounced as Popper declared it to be. Thus, there is no inconsistency in holding that a universal scientific belief is false despite any number of positive instances; and there is no inconsistency either in holding that a universal scientific belief is true despite the evidence of a negative instance. For the belief that an instance is negative is itself a scientific belief and may be falsified by experimental evidence which we accept and which is inconsistent with it. When, for example, we draw a right-angled triangle on the surface of a sphere using parts of three great circles for its sides, and discover that for this triangle Pythagoras' Theorem does not hold, we may decide that this apparently negative instance is not really negative because it is not a genuine instance at all. Triangles drawn on the surfaces of spheres are not the sort of triangles which fall within the scope of Pythagoras' Theorem. Falsification, that is to say, is no more capable of yielding conclusive rejections of scientific belief than verification is of yielding conclusive acceptances of scientific beliefs. The asymmetry between falsification and verification, therefore, has less logical significance than Popper supposed. We should, though, resist this reasoning. Falsifications may not be conclusive, for the acceptances on which rejections are based are always provisional acceptances. But, nevertheless, it remains the case that, in falsification, if we accept falsifying claims then, to remain consistent, we must reject falsified claims. On the other hand, although verifications are also not conclusive, our acceptance or rejection of verifying instances has no implications concerning the acceptance or rejection of verified claims. Falsifying claims sometimes give us a good reason for rejecting a scientific belief, namely when the claims are accepted. But verifying claims, even when accepted, give us no good and appropriate reason for accepting any scientific belief, because any such reason would have to be inductive to be appropriate and there are no good inductive reasons.According to Popper, the statement "Scientific beliefs are universal in character" implies that....

MCQ-> The broad scientific understanding today is that our planet is experiencing a warming trend over and above natural and normal variations that is almost certainly due to human activities associated with large-scale manufacturing. The process began in the late 1700s with the Industrial Revolution, when manual labor, horsepower, and water power began to be replaced by or enhanced by machines. This revolution, over time, shifted Britain, Europe, and eventually North America from largely agricultural and trading societies to manufacturing ones, relying on machinery and engines rather than tools and animals.The Industrial Revolution was at heart a revolution in the use of energy and power. Its beginning is usually dated to the advent of the steam engine, which was based on the conversion of chemical energy in wood or coal to thermal energy and then to mechanical work primarily the powering of industrial machinery and steam locomotives. Coal eventually supplanted wood because, pound for pound, coal contains twice as much energy as wood (measured in BTUs, or British thermal units, per pound) and because its use helped to save what was left of the world's temperate forests. Coal was used to produce heat that went directly into industrial processes, including metallurgy, and to warm buildings, as well as to power steam engines. When crude oil came along in the mid- 1800s, still a couple of decades before electricity, it was burned, in the form of kerosene, in lamps to make light replacing whale oil. It was also used to provide heat for buildings and in manufacturing processes, and as a fuel for engines used in industry and propulsion.In short, one can say that the main forms in which humans need and use energy are for light, heat, mechanical work and motive power, and electricity which can be used to provide any of the other three, as well as to do things that none of those three can do, such as electronic communications and information processing. Since the Industrial Revolution, all these energy functions have been powered primarily, but not exclusively, by fossil fuels that emit carbon dioxide (CO2), To put it another way, the Industrial Revolution gave a whole new prominence to what Rochelle Lefkowitz, president of Pro-Media Communications and an energy buff, calls "fuels from hell" - coal, oil, and natural gas. All these fuels from hell come from underground, are exhaustible, and emit CO2 and other pollutants when they are burned for transportation, heating, and industrial use. These fuels are in contrast to what Lefkowitz calls "fuels from heaven" -wind, hydroelectric, tidal, biomass, and solar power. These all come from above ground, are endlessly renewable, and produce no harmful emissions.Meanwhile, industrialization promoted urbanization, and urbanization eventually gave birth to suburbanization. This trend, which was repeated across America, nurtured the development of the American car culture, the building of a national highway system, and a mushrooming of suburbs around American cities, which rewove the fabric of American life. Many other developed and developing countries followed the American model, with all its upsides and downsides. The result is that today we have suburbs and ribbons of highways that run in, out, and around not only America s major cities, but China's, India's, and South America's as well. And as these urban areas attract more people, the sprawl extends in every direction.All the coal, oil, and natural gas inputs for this new economic model seemed relatively cheap, relatively inexhaustible, and relatively harmless-or at least relatively easy to clean up afterward. So there wasn't much to stop the juggernaut of more people and more development and more concrete and more buildings and more cars and more coal, oil, and gas needed to build and power them. Summing it all up, Andy Karsner, the Department of Energy's assistant secretary for energy efficiency and renewable energy, once said to me: "We built a really inefficient environment with the greatest efficiency ever known to man."Beginning in the second half of the twentieth century, a scientific understanding began to emerge that an excessive accumulation of largely invisible pollutants-called greenhouse gases - was affecting the climate. The buildup of these greenhouse gases had been under way since the start of the Industrial Revolution in a place we could not see and in a form we could not touch or smell. These greenhouse gases, primarily carbon dioxide emitted from human industrial, residential, and transportation sources, were not piling up along roadsides or in rivers, in cans or empty bottles, but, rather, above our heads, in the earth's atmosphere. If the earth's atmosphere was like a blanket that helped to regulate the planet's temperature, the CO2 buildup was having the effect of thickening that blanket and making the globe warmer.Those bags of CO2 from our cars float up and stay in the atmosphere, along with bags of CO2 from power plants burning coal, oil, and gas, and bags of CO2 released from the burning and clearing of forests, which releases all the carbon stored in trees, plants, and soil. In fact, many people don't realize that deforestation in places like Indonesia and Brazil is responsible for more CO2 than all the world's cars, trucks, planes, ships, and trains combined - that is, about 20 percent of all global emissions. And when we're not tossing bags of carbon dioxide into the atmosphere, we're throwing up other greenhouse gases, like methane (CH4) released from rice farming, petroleum drilling, coal mining, animal defecation, solid waste landfill sites, and yes, even from cattle belching. Cattle belching? That's right-the striking thing about greenhouse gases is the diversity of sources that emit them. A herd of cattle belching can be worse than a highway full of Hummers. Livestock gas is very high in methane, which, like CO2, is colorless and odorless. And like CO2, methane is one of those greenhouse gases that, once released into the atmosphere, also absorb heat radiating from the earth's surface. "Molecule for molecule, methane's heat-trapping power in the atmosphere is twenty-one times stronger than carbon dioxide, the most abundant greenhouse gas.." reported Science World (January 21, 2002). “With 1.3 billion cows belching almost constantly around the world (100 million in the United States alone), it's no surprise that methane released by livestock is one of the chief global sources of the gas, according to the U.S. Environmental Protection Agency ... 'It's part of their normal digestion process,' says Tom Wirth of the EPA. 'When they chew their cud, they regurgitate [spit up] some food to rechew it, and all this gas comes out.' The average cow expels 600 liters of methane a day, climate researchers report." What is the precise scientific relationship between these expanded greenhouse gas emissions and global warming? Experts at the Pew Center on Climate Change offer a handy summary in their report "Climate Change 101. " Global average temperatures, notes the Pew study, "have experienced natural shifts throughout human history. For example; the climate of the Northern Hemisphere varied from a relatively warm period between the eleventh and fifteenth centuries to a period of cooler temperatures between the seventeenth century and the middle of the nineteenth century. However, scientists studying the rapid rise in global temperatures during the late twentieth century say that natural variability cannot account for what is happening now." The new factor is the human factor-our vastly increased emissions of carbon dioxide and other greenhouse gases from the burning of fossil fuels such as coal and oil as well as from deforestation, large-scale cattle-grazing, agriculture, and industrialization.“Scientists refer to what has been happening in the earth’s atmosphere over the past century as the ‘enhanced greenhouse effect’”, notes the Pew study. By pumping man- made greenhouse gases into the atmosphere, humans are altering the process by which naturally occurring greenhouse gases, because of their unique molecular structure, trap the sun’s heat near the earth’s surface before that heat radiates back into space."The greenhouse effect keeps the earth warm and habitable; without it, the earth's surface would be about 60 degrees Fahrenheit colder on average. Since the average temperature of the earth is about 45 degrees Fahrenheit, the natural greenhouse effect is clearly a good thing. But the enhanced greenhouse effect means even more of the sun's heat is trapped, causing global temperatures to rise. Among the many scientific studies providing clear evidence that an enhanced greenhouse effect is under way was a 2005 report from NASA's Goddard Institute for Space Studies. Using satellites, data from buoys, and computer models to study the earth's oceans, scientists concluded that more energy is being absorbed from the sun than is emitted back to space, throwing the earth's energy out of balance and warming the globe."Which of the following statements is correct? (I) Greenhouse gases are responsible for global warming. They should be eliminated to save the planet (II) CO2 is the most dangerous of the greenhouse gases. Reduction in the release of CO2 would surely bring down the temperature (III) The greenhouse effect could be traced back to the industrial revolution. But the current development and the patterns of life have enhanced their emissions (IV) Deforestation has been one of the biggest factors contributing to the emission of greenhouse gases Choose the correct option:....

MCQ-> Read the following passage carefully and answer the questions given below it. Certain words/phrases have been printed in bold tohelp you locate them while answering some of the questions. During the last few years, a lot of hype has been heaped on the BRICS (Brazil, Russia, India, China, and South Africa). With their large populations and rapid growth, these countries, so the argument goes, will soon become some of the largest economies in the world and, in the case of China, the largest of all by as early as 2020. But the BRICS, as well as many other emerging-market economieshave recently experienced a sharp economic slowdown. So, is the honeymoon over? Brazil’s GDP grew by only 1% last year, and may not grow by more than 2% this year, with its potential growth barely above 3%. Russia’s economy may grow by barely 2% this year, with potential growth also at around 3%, despite oil prices being around $100 a barrel. India had a couple of years of strong growth recently (11.2% in 2010 and 7.7% in 2011) but slowed to 4% in 2012. China’s economy grew by 10% a year for the last three decades, but slowed to 7.8% last year and risks a hard landing. And South Africa grew by only 2.5% last year and may not grow faster than 2% this year. Many other previously fast-growing emerging-market economies – for example, Turkey, Argentina, Poland, Hungary, and many in Central and Eastern Europe are experiencing a similar slowdown. So, what is ailing the BRICS and other emerging markets? First, most emerging-market economies were overheating in 2010-2011, with growth above potential and inflation rising and exceeding targets. Many of them thus tightened monetary policy in 2011, with consequences for growth in 2012 that have carried over into this year. Second, the idea that emerging-market economies could fully decouple from economic weakness in advanced economies was farfetched : recession in the eurozone, near-recession in the United Kingdom and Japan in 2011-2012, and slow economic growth in the United States were always likely to affect emerging market performance negatively – via trade, financial links, and investor confidence. For example, the ongoing euro zone downturn has hurt Turkey and emergingmarket economies in Central and Eastern Europe, owing to trade links. Third, most BRICS and a few other emerging markets have moved toward a variant of state capitalism. This implies a slowdown in reforms that increase the private sector’s productivity and economic share, together with a greater economic role for state-owned enterprises (and for state-owned banks in the allocation of credit and savings), as well as resource nationalism, trade protectionism, import substitution industrialization policies, and imposition of capital controls. This approach may have worked at earlier stages of development and when the global financial crisis caused private spending to fall; but it is now distorting economic activity and depressing potential growth. Indeed, China’s slowdown reflects an economic model that is, as former Premier Wen Jiabao put it, “unstable, unbalanced, uncoordinated, and unsustainable,” and that now is adversely affecting growth in emerging Asia and in commodity-exporting emerging markets from Asia to Latin America and Africa. The risk that China will experience a hard landing in the next two years may further hurt many emerging economies. Fourth, the commodity super-cycle that helped Brazil, Russia, South Africa, and many other commodity-exporting emerging markets may be over. Indeed, a boom would be difficult to sustain, given China’s slowdown, higher investment in energysaving technologies, less emphasis on capital-and resource-oriented growth models around the world, and the delayed increase in supply that high prices induced. The fifth, and most recent, factor is the US Federal Reserve’s signals that it might end its policy of quantitative easing earlier than expected, and its hints of an even tual exit from zero interest rates. both of which have caused turbulence in emerging economies’ financial markets. Even before the Fed’s signals, emergingmarket equities and commodities had underperformed this year, owing to China’s slowdown. Since then, emerging-market currencies and fixed-income securities (government and corporate bonds) have taken a hit. The era of cheap or zerointerest money that led to a wall of liquidity chasing high yields and assets equities, bonds, currencies, and commodities – in emerging markets is drawing to a close. Finally, while many emerging-market economies tend to run current-account surpluses, a growing number of them – including Turkey, South Africa, Brazil, and India – are running deficits. And these deficits are now being financed in riskier ways: more debt than equity; more short-term debt than longterm debt; more foreign-currency debt than local-currency debt; and more financing from fickle cross-border interbank flows. These countries share other weaknesses as well: excessive fiscal deficits, abovetarget inflation, and stability risk (reflected not only in the recent political turmoil in Brazil and Turkey, but also in South Africa’s labour strife and India’s political and electoral uncertainties). The need to finance the external deficit and to avoid excessive depreciation (and even higher inflation) calls for raising policy rates or keeping them on hold at high levels. But monetary tightening would weaken already-slow growth. Thus, emerging economies with large twin deficits and other macroeconomic fragilities may experience further downward pressure on their financial markets and growth rates. These factors explain why growth in most BRICS and many other emerging markets has slowed sharply. Some factors are cyclical, but others – state capitalism, the risk of a hard landing in China, the end of the commodity supercycle -are more structural. Thus, many emerging markets’ growth rates in the next decade may be lower than in the last – as may the outsize returns that investors realised from these economies’ financial assets (currencies, equities. bonds, and commodities). Of course, some of the better-managed emerging-market economies will continue to experitnce rapid growth and asset outperformance. But many of the BRICS, along with some other emerging economies, may hit a thick wall, with growth and financial markets taking a serious beating.Which of the following statement(s) is/are true as per the given information in the passage ? A. Brazil’s GDP grew by only 1% last year, and is expected to grow by approximately 2% this year. B. China’s economy grew by 10% a year for the last three decades but slowed to 7.8% last year. C. BRICS is a group of nations — Barzil, Russia, India China and South Africa.....

MCQ-> Read the passage carefully and answer the questions givenMore and more companies, government agencies, educational institutions and philanthropic organisations are today in the grip of a new phenomenon: ‘metric fixation’. The key components of metric fixation are the belief that it is possible - and desirable - to replace professional judgment (acquired through personal experience and talent) with numerical indicators of comparative performance based upon standardised data (metrics); and that the best way to motivate people within these organisations is by attaching rewards and penalties to their measured performance. The rewards can be monetary, in the form of pay for performance, say, or reputational, in the form of college rankings, hospital ratings, surgical report cards and so on. But the most dramatic negative effect of metric fixation is its propensity to incentivise gaming: that is, encouraging professionals to maximise the metrics in ways that are at odds with the larger purpose of the organisation. If the rate of major crimes in a district becomes the metric according to which police officers are promoted, then some officers will respond by simply not recording crimes or downgrading them from major offences to misdemeanours. Or take the case of surgeons. When the metrics of success and failure are made public - affecting their reputation and income - some surgeons will improve their metric scores by refusing to operate on patients with more complex problems, whose surgical outcomes are more likely to be negative. Who suffers? The patients who don’t get operated upon.When reward is tied to measured performance, metric fixation invites just this sort of gaming. But metric fixation also leads to a variety of more subtle unintended negative consequences. These include goal displacement, which comes in many varieties: when performance is judged by a few measures, and the stakes are high (keeping one’s job, getting a pay rise or raising the stock price at the time that stock options are vested), people focus on satisfying those measures - often at the expense of other, more important organisational goals that are not measured. The best-known example is ‘teaching to the test’, a widespread phenomenon that has distorted primary and secondary education in the United States since the adoption of the No Child Left Behind Act of 2001.Short-termism is another negative. Measured performance encourages what the US sociologist Robert K Merton in 1936 called ‘the imperious immediacy of interests … where the actor’s paramount concern with the foreseen immediate consequences excludes consideration of further or other consequences’. In short, advancing short-term goals at the expense of long-range considerations. This problem is endemic to publicly traded corporations that sacrifice long-term research and development, and the development of their staff, to the perceived imperatives of the quarterly report.To the debit side of the ledger must also be added the transactional costs of metrics: the expenditure of employee time by those tasked with compiling and processing the metrics in the first place - not to mention the time required to actually read them. . . .All of the following can be a possible feature of the No Child Left Behind Act of 2001, EXCEPT:
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