When a low carbon steel is heated upto lower critical temperature, ?->(Show Answer!)

1. When a low carbon steel is heated upto lower critical temperature,

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MCQ-> Our propensity to look out for regularities, and to impose laws upon nature, leads to the psychological phenomenon of dogmatic thinking or, more generally, dogmatic behaviour: we expect regularities everywhere and attempt to find them even where there are none; events which do not yield to these attempts we are inclined to treat as a kind of `background noise’; and we stick to our expectations even when they are inadequate and we ought to accept defeat. This dogmatism is to some extent necessary. It is demanded by a situation which can only be dealt with by forcing our conjectures upon the world. Moreover, this dogmatism allows us to approach a good theory in stages, by way of approximations: if we accept defeat too easily, we may prevent ourselves from finding that we were very nearly right.It is clear that this dogmatic attitude; which makes us stick to our first impressions, is indicative of a strong belief; while a critical attitude, which is ready to modify its tenets, which admits doubt and demands tests, is indicative of a weaker belief. Now according to Hume’s theory, and to the popular theory, the strength of a belief should be a product of repetition; thus it should always grow with experience, and always be greater in less primitive persons. But dogmatic thinking, an uncontrolled wish to impose regularities, a manifest pleasure in rites and in repetition as such, is characteristic of primitives and children; and increasing experience and maturity sometimes create an attitude of caution and criticism rather than of dogmatism.My logical criticism of Hume’s psychological theory, and the considerations connected with it, may seem a little removed from the field of the philosophy of science. But the distinction between dogmatic and critical thinking, or the dogmatic and the critical attitude, brings us right back to our central problem. For the dogmatic attitude is clearly related to the tendency to verify our laws and schemata by seeking to apply them and to confirm them, even to the point of neglecting refutations, whereas the critical attitude is one of readiness to change them - to test them; to refute them; to falsify them, if possible. This suggests that we may identify the critical attitude with the scientific attitude, and the dogmatic attitude with the one which we have described as pseudo-scientific. It further suggests that genetically speaking the pseudo-scientific attitude is more primitive than, and prior to, the scientific attitude: that it is a pre-scientific attitude. And this primitivity or priority also has its logical aspect. For the critical attitude is not so much opposed to the dogmatic attitude as super-imposed upon it: criticism must be directed against existing and influential beliefs in need of critical revision – in other words, dogmatic beliefs. A critical attitude needs for its raw material, as it were, theories or beliefs which are held more or less dogmatically.Thus, science must begin with myths, and with the criticism of myths; neither with the collection of observations, nor with the invention of experiments, but with the critical discussion of myths, and of magical techniques and practices. The scientific tradition is distinguished from the pre-scientific tradition in having two layers. Like the latter, it passes on its theories; but it also passes on a critical attitude towards them. The theories are passed on, not as dogmas, but rather with the challenge to discuss them and improve upon them.The critical attitude, the tradition of free discussion of theories with the aim of discovering their weak spots so that they may be improved upon, is the attitude of reasonableness, of rationality. From the point of view here developed, all laws, all theories, remain essentially tentative, or conjectural, or hypothetical, even when we feel unable to doubt them any longer. Before a theory has been refuted we can never know in what way it may have to be modified.In the context of science, according to the passage, the interaction of dogmatic beliefs and critical attitude can be best described as:
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MCQ->When a low carbon steel is heated upto lower critical temperature,....

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 at the end.Passage 4Public sector banks (PSBs) are pulling back on credit disbursement to lower rated companies, as they keep a closer watch on using their own scarce capital and the banking regulator heightens its scrutiny on loans being sanctioned. Bankers say the Reserve Bank of India has started strictly monitoring how banks are utilizing their capital. Any big-ticket loan to lower rated companies is being questioned. Almost all large public sector banks that reported their first quarter results so far have showed a contraction in credit disbursal on a year-to-date basis, as most banks have shifted to a strategy of lending largely to government-owned "Navratna" companies and highly rated private sector companies. On a sequential basis too, banks have grown their loan book at an anaemic rate.To be sure, in the first quarter, loan demand is not quite robust. However, in the first quarter last year, banks had healthier loan growth on a sequential basis than this year. The country's largest lender State Bank of India grew its loan book at only 1.21% quarter-on-quarter. Meanwhile, Bank of Baroda and Punjab National Bank shrank their loan book by 1.97% and 0.66% respectively in the first quarter on a sequential basis.Last year, State Bank of India had seen sequential loan growth of 3.37%, while Bank of Baroda had seen a smaller contraction of 0.22%. Punjab National Bank had seen a growth of 0.46% in loan book between the January-March and April-June quarters last year. On a year-to-date basis, SBI's credit growth fell more than 2%, Bank of Baroda's credit growth contracted 4.71% and Bank of India's credit growth shrank about 3%. SBI chief Arundhati Bhattacharya said the bank's year-to-date credit growth fell as the bank focused on ‘A’ rated customers. About 90% of the loans in the quarter were given to high-rated companies. "Part of this was a conscious decision and part of it is because we actually did not get good fresh proposals in the quarter," Bhattacharya said.According to bankers, while part of the credit contraction is due to the economic slowdown, capital constraints and reluctance to take on excessive risk has also played a role. "Most of the PSU banks are facing pressure on capital adequacy. It is challenging to maintain 9% core capital adequacy. The pressure on monitoring capital adequacy and maintaining capital buffer is so strict that you cannot grow aggressively," said Rupa Rege Nitsure, chief economist at Bank of Baroda.Nitsure said capital conservation pressures will substantially cut down "irrational expansion of loans" in some smaller banks, which used to grow at a rate much higher than the industry average. The companies coming to banks, in turn, will have to make themselves more creditworthy for banks to lend. "The conservation of capital is going to inculcate a lot of discipline in both banks and borrowers," she said.For every loan that a bank disburses, some amount of money is required to be set aside as provision. Lower the credit rating of the company, riskier the loan is perceived to be. Thus, the bank is required to set aside more capital for a lower rated company than what it otherwise would do for a higher rated client. New international accounting norms, known as Basel III norms, require banks to maintain higher capital and higher liquidity. They also require a bank to set aside "buffer" capital to meet contingencies. As per the norms, a bank's total capital adequacy ratio should be 12% at any time, in which tier-I, or the core capital, should be at 9%. Capital adequacy is calculated by dividing total capital by risk-weighted assets. If the loans have been given to lower rated companies, risk weight goes up and capital adequacy falls.According to bankers, all loan decisions are now being assessed on the basis of the capital that needs to be set aside as provision against the loan and as a result, loans to lower rated companies are being avoided. According to a senior banker with a public sector bank, the capital adequacy situation is so precarious in some banks that if the risk weight increases a few basis points, the proposal gets cancelled. The banker did not wish to be named. One basis point is one hundredth of a percentage point. Bankers add that the Reserve Bank of India has also started strictly monitoring how banks are utilising their capital. Any big-ticket loan to lower rated companies is being questioned.In this scenario, banks are looking for safe bets, even if it means that profitability is being compromised. "About 25% of our loans this quarter was given to Navratna companies, who pay at base rate. This resulted in contraction of our net interest margin (NIM)," said Bank of India chairperson V.R. Iyer, while discussing the bank's first quarter results with the media. Bank of India's NIM, or the difference between yields on advances and cost of deposits, a key gauge of profitability, fell in the first quarter to 2.45% from 3.07% a year ago, as the bank focused on lending to highly rated customers.Analysts, however, say the strategy being followed by banks is short-sighted. "A high rated client will take loans at base rate and will not give any fee income to a bank. A bank will never be profitable that way. Besides, there are only so many PSU companies to chase. All banks cannot be chasing them all at a time. Fact is, the banks are badly hit by NPA and are afraid to lend now to big projects. They need capital, true, but they have become risk-averse," said a senior analyst with a local brokerage who did not wish to be named.Various estimates suggest that Indian banks would require more than Rs. 2 trillion of additional capital to have this kind of capital adequacy ratio by 2019. The central government, which owns the majority share of these banks, has been cutting down on its commitment to recapitalize the banks. In 2013-14, the government infused Rs. 14,000 crore in its banks. However, in 2014-15, the government will infuse just Rs. 11,200 crore.Which of the following statements is correct according to the passage?
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MCQ->When a low carbon steel is heated upto upper critical temperature....