1. Which type of camshaft drive mechanism is used in over head camshaft engine?





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MCQ->Which type of camshaft drive mechanism is used in over head camshaft engine?....
MCQ-> Recently I spent several hours sitting under a tree in my garden with the social anthropologist William Ury, a Harvard University professor who specializes in the art of negotiation and wrote the bestselling book, Getting to Yes. He captivated me with his theory that tribalism protects people from their fear of rapid change. He explained that the pillars of tribalism that humans rely on for security would always counter any significant cultural or social change. In this way, he said, change is never allowed to happen too fast. Technology, for example, is a pillar of society. Ury believes that every time technology moves in a new or radical direction, another pillar such as religion or nationalism will grow stronger in effect, the traditional and familiar will assume greater importance to compensate for the new and untested. In this manner, human tribes avoid rapid change that leaves people insecure and frightened.But we have all heard that nothing is as permanent as change. Nothing is guaranteed. Pithy expressions, to be sure, but no more than cliches. As Ury says, people don’t live that way from day-to-day. On the contrary, they actively seek certainty and stability. They want to know they will be safe.Even so we scare ourselves constantly with the idea of change. An IBM CEO once said: ‘We only re-structure for a good reason, and if we haven’t re-structured in a while, that’s a good reason.’ We are scared that competitors, technology and the consumer will put us Out of business — so we have to change all the time just to stay alive. But if we asked our fathers and grandfathers, would they have said that they lived in a period of little change? Structure may not have changed much. It may just be the speed with which we do things.Change is over-rated, anyway, consider the automobile. It’s an especially valuable example, because the auto industry has spent tens of billions of dollars on research and product development in the last 100 years. Henry Ford’s first car had a metal chassis with an internal combustion, gasoline-powered engine, four wheels with rubber types, a foot operated clutch assembly and brake system, a steering wheel, and four seats, and it could safely do 1 8 miles per hour. A hundred years and tens of thousands of research hours later, we drive cars with a metal chassis with an internal combustion, gasoline-powered engine, four wheels with rubber tyres a foot operated clutch assembly and brake system, a steering wheel, four seats – and the average speed in London in 2001 was 17.5 miles per hour!That’s not a hell of a lot of return for the money. Ford evidently doesn’t have much to teach us about change. The fact that they’re still manufacturing cars is not proof that Ford Motor Co. is a sound organization, just proof that it takes very large companies to make cars in great quantities — making for an almost impregnable entry barrier.Fifty years after the development of the jet engine, planes are also little changed. They’ve grown bigger, wider and can carry more people. But those are incremental, largely cosmetic changes.Taken together, this lack of real change has come to man that in travel — whether driving or flying — time and technology have not combined to make things much better. The safety and design have of course accompanied the times and the new volume of cars and flights, but nothing of any significance has changed in the basic assumptions of the final product.At the same time, moving around in cars or aero-planes becomes less and less efficient all the time Not only has there been no great change, but also both forms of transport have deteriorated as more people clamour to use them. The same is true for telephones, which took over hundred years to become mobile or photographic film, which also required an entire century to change.The only explanation for this is anthropological. Once established in calcified organizations, humans do two things: sabotage changes that might render people dispensable, and ensure industry-wide emulation. In the 960s, German auto companies developed plans to scrap the entire combustion engine for an electrical design. (The same existed in the 1970s in Japan, and in the 1980s in France.) So for 40 years we might have been free of the wasteful and ludicrous dependence on fossil fuels. Why didn’t it go anywhere? Because auto executives understood pistons and carburettors, and would be loath to cannibalize their expertise, along with most of their factoriesAccording to the above passage, which of the following statements is true?
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MCQ-> Cells are the ultimate multi-taskers: they can switch on genes and carry out their orders, talk to each other, divide in two, and much more, all at the same time. But they couldn’t do any of these tricks without a power source to generate movement. The inside of a cell bustles with more traffic than Delhi roads, and, like all vehicles, the cell’s moving parts need engines. Physicists and biologists have looked ‘under the hood’ of the cell and laid out the nuts and bolts of molecular engines.The ability of such engines to convert chemical energy into motion is the envy nanotechnology researchers looking for ways to power molecule-sized devices. Medical researchers also want to understand how these engines work. Because these molecules are essential for cell division, scientists hope to shut down the rampant growth of cancer cells by deactivating certain motors. Improving motor-driven transport in nerve cells may also be helpful for treating diseases such as Alzheimer’s, Parkinson’s or ALS, also known as Lou Gehrig’s disease.We wouldn’t make it far in life without motor proteins. Our muscles wouldn’t contract. We couldn’t grow, because the growth process requires cells to duplicate their machinery and pull the copies apart. And our genes would be silent without the services of messenger RNA, which carries genetic instructions over to the cell’s protein-making factories. The movements that make these cellular activities possible occur along a complex network of threadlike fibers, or polymers, along which bundles of molecules travel like trams. The engines that power the cell’s freight are three families of proteins, called myosin, kinesin and dynein. For fuel, these proteins burn molecules of ATP, which cells make when they break down the carbohydrates and fats from the foods we eat. The energy from burning ATP causes changes in the proteins’ shape that allow them to heave themselves along the polymer track. The results are impressive: In one second, these molecules can travel between 50 and 100 times their own diameter. If a car with a five-foot-wide engine were as efficient, it would travel 170 to 340 kilometres per hour.Ronald Vale, a researcher at the Howard Hughes Medical Institute and the University of California at San Francisco, and Ronald Milligan of the Scripps Research Institute have realized a long-awaited goal by reconstructing the process by which myosin and kinesin move, almost down to the atom. The dynein motor, on the other hand, is still poorly understood. Myosin molecules, best known for their role in muscle contraction, form chains that lie between filaments of another protein called actin. Each myosin molecule has a tiny head that pokes out from the chain like oars from a canoe. Just as rowers propel their boat by stroking their oars through the water, the myosin molecules stick their heads into the actin and hoist themselves forward along the filament. While myosin moves along in short strokes, its cousin kinesin walks steadily along a different type of filament called a microtubule. Instead of using a projecting head as a lever, kinesin walks on two ‘legs’. Based on these differences, researchers used to think that myosin and kinesin were virtually unrelated. But newly discovered similarities in the motors’ ATP-processing machinery now suggest that they share a common ancestor — molecule. At this point, scientists can only speculate as to what type of primitive cell-like structure this ancestor occupied as it learned to burn ATP and use the energy to change shape. “We’ll never really know, because we can’t dig up the remains of ancient proteins, but that was probably a big evolutionary leap,” says Vale.On a slightly larger scale, loner cells like sperm or infectious bacteria are prime movers that resolutely push their way through to other cells. As L. Mahadevan and Paul Matsudaira of the Massachusetts Institute of Technology explain, the engines in this case are springs or ratchets that are clusters of molecules, rather than single proteins like myosin and kinesin. Researchers don’t yet fully understand these engines’ fueling process or the details of how they move, but the result is a force to be reckoned with. For example, one such engine is a spring-like stalk connecting a single-celled organism called a vorticellid to the leaf fragment it calls home. When exposed to calcium, the spring contracts, yanking the vorticellid down at speeds approaching three inches (eight centimetres) per second.Springs like this are coiled bundles of filaments that expand or contract in response to chemical cues. A wave of positively charged calcium ions, for example, neutralizes the negative charges that keep the filaments extended. Some sperm use spring-like engines made of actin filaments to shoot out a barb that penetrates the layers that surround an egg. And certain viruses use a similar apparatus to shoot their DNA into the host’s cell. Ratchets are also useful for moving whole cells, including some other sperm and pathogens. These engines are filaments that simply grow at one end, attracting chemical building blocks from nearby. Because the other end is anchored in place, the growing end pushes against any barrier that gets in its way.Both springs and ratchets are made up of small units that each move just slightly, but collectively produce a powerful movement. Ultimately, Mahadevan and Matsudaira hope to better understand just how these particles create an effect that seems to be so much more than the sum of its parts. Might such an understanding provide inspiration for ways to power artificial nano-sized devices in the future? “The short answer is absolutely,” says Mahadevan. “Biology has had a lot more time to evolve enormous richness in design for different organisms. Hopefully, studying these structures will not only improve our understanding of the biological world, it will also enable us to copy them, take apart their components and recreate them for other purpose.”According to the author, research on the power source of movement in cells can contribute to
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MCQ-> Read the following passage carefully and answer the questions given at the end.The tight calendar had calmed him, as did the constant exertion of his authority as a judge. How he relished his power over the classes that had kept his family pinned under their heels for centuries - like the stenographer, for example, who was a Brahmin. There he was, now crawling into a tiny tent to the side, and there was Jemubhai reclining like a king in a bed carved out of teak, hung with mosquito netting."Bed tea", the cook would shout "Baaad tee". He would sit up to drink.6:30: he'd bathe in water that had been heated over the fire so it was redolent with the smell of wood smoke and flecked with ash. With a dusting of powder he graced his newly washed face, with a daub of pomade, his hair. Crunched up toast like charcoal from having been toasted upon the flame, with marmalade over the burn.8:30: he rode into the fields with the local officials and everyone else in the village going along for fun. Followed by an orderly holding an umbrella over his head to shield him from the glare, he measured the fields and checked to make sure his yield estimate matched the headman's statement. Farms were growing less than ten maunds an acre of rice or wheat, and at two rupees a maund, every single man in a village, sometimes, was in debt to the bania. (Nobody knew that Jemubhai himself was noosed, of course, that long ago in the little town of Piphit in Gujarat, money-lenders had sniffed out in him a winning combination of ambition and poverty ... that they still sat waiting cross-legged on a soiled mat in the market, snapping their toes, cracking their knuckles in anticipation of repayment .... ) 2.00: after lunch, the judge sat at his desk under a tree to try cases, usually in a cross mood, for he disliked the informality, hated the splotch of leaf shadow on him imparting an untidy mongrel look. Also, there was a worse aspect of contamination and corruption: he heard cases in Hindi, but they were recorded in Urdu by the stenographer and translated by the judge into a second record in English, although his own command of Hindi and Urdu was tenuous; the witnesses who couldn't read at all put their thumbprints at the bottom of "Read Over and Acknowledged Correct", as instructed. Nobody could be sure how much of the truth had fallen between languages, between languages and illiteracy; the clarity that justice demanded was nonexistent. Still, despite the leaf shadow and language confusion, he acquired a fearsome reputation for his speech that seemed to belong to no language at all, and for his face like a mask that conveyed something beyond human fallibility. The expression and manner honed here would carry him, eventually, all the way to the high court in Lucknow where, annoyed by lawless pigeons shuttlecocking about those tall, shadowy halls, he would preside, white powdered wig over white powdered face, hammer in hand.His photograph, thus attired, thus annoyed, was still up on the wall, in a parade of history glorifying the progress of Indian law and order. 4:30: tea had to be perfect, drop scones made in the frying pan. He would embark on them with forehead wrinkled, as if angrily mulling over something important, and then, as it would into his retirement, the draw of the sweet took over, and his stern work face would hatch an expression of tranquillity.5:30: out he went into the countryside with his fishing rod or gun. The countryside was full of game; lariats of migratory birds lassoed the sky in October; quail and partridge with lines of babies strung out behind whirred by like nursery toys that emit sound with movement; pheasant - fat foolish creatures, made to be shot - went scurrying through the bushes. The thunder of gunshot roiled away, the leaves shivered, and he experienced the profound silence that could come only after violence. One thing was always missing, though, the proof of the pudding, the prize of the action. the manliness in manhood, the partridge for the pot. because he returned with - Nothing!He was a terrible shot.8:00: the cook saved his reputation, cooked a chicken, brought it forth, proclaimed it "roast bastard", just as in the Englishman's favourite joke book of natives using incorrect English. But sometimes, eating that roast bustard, the judge felt the joke might also be on him, and he called for another rum, took a big gulp, and kept eating feeling as if he were eating himself, since he, too, was (was he?) part of the fun ....9:00: sipping Ovaltine, he filled out the registers with the day's gleanings. The Petromax lantern would be lit - what a noise it made - insects fording the black to dive - bomb him with soft flowers (moths), with iridescence (beetles). Lines, columns, and squares. He realized truth was best looked at in tiny aggregates, for many baby truths could yet add up to one big size unsavory lie. Last, in his diary also to be submitted to his superiors, he recorded the random observations of a cultured man, someone who was observant, schooled in literature as well as economics; and he made up hunting triumphs: two partridge ... one deer with thirty- inch horns....11:00: he had a hot water bottle in winter, and, in all seasons, to the sound of the wind buffeting the trees and the cook's snoring, he fell asleep.Which of the following statements is incorrect?
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MCQ-> Answer questions on the basis of information given in the following case. Bright Engineering College (BEC) has listed 20 elective courses for the next term and students have to choose any 7 of them. Simran, a student of BEC, notices that there are three categories of electives: Job - oriented (J), Quantitative - oriented (Q) and Grade - oriented (G). Among these 20 electives, some electives are both Job and Grade - oriented but are not Quantitative - oriented (JG type). QJ type electives are both job and Quantitative - oriented but are not Grade - oriented and QG type electives are both Quantitative and Grade - oriented but are not Job - oriented. Simran also notes that the total number of QJ type electives is 2 less than QG type electives. Similarly, the total number of QG type electives is 2 less than JG type and there is only 1 common elective (JQG) across three categories. Furthermore, the number of only Quantitative - oriented electives is same as only Job - oriented electives, but less than the number of only Grade - oriented electives. Each elective has at least one registration and there is at least one elective in each category, or combinations of categories.On her way back Simran met her friend Raj and shared the above information. Raj is preparing for XAT and is only interested in Grade - oriented (G) electives. He wanted to know the number of G - type electives being offered. Simran replied, “You have all the information. Calculate the number of G - type electives yourself. It would help your XAT preparation”. Raj calculates correctly and says that there can be _______ possible answers. Which of the following options would b est fit the blank above?
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