1. What is the current through R2?





Write Comment

Type in
(Press Ctrl+g to toggle between English and the chosen language)

Comments

Tags
Show Similar Question And Answers
QA->A transformer has a turn ration of 1:If the current in the primary has a peak value of 5A, then the current in the secondary will be :....
QA->When current flows through a metallic conductor, heat is produced, known as :....
QA->The current and enclosure arranged below is punched and a tag is passed through the hole is :....
QA->Which will you put into pure water in order to pass electric current through it?....
QA->‘our education has got to be revolutionized. The brain must be educated through hands. Those who do not train hands, and go through the ordinary suit of education, lack music in their life’. Who said this ?....
MCQ-> In a modern computer, electronic and magnetic storage technologies play complementary roles. Electronic memory chips are fast but volatile (their contents are lost when the computer is unplugged). Magnetic tapes and hard disks are slower, but have the advantage that they are non-volatile, so that they can be used to store software and documents even when the power is off.In laboratories around the world, however, researchers are hoping to achieve the best of both worlds. They are trying to build magnetic memory chips that could be used in place of today’s electronics. These magnetic memories would be nonvolatile; but they would also he faster, would consume less power, and would be able to stand up to hazardous environments more easily. Such chips would have obvious applications in storage cards for digital cameras and music- players; they would enable handheld and laptop computers to boot up more quickly and to operate for longer; they would allow desktop computers to run faster; they would doubtless have military and space-faring advantages too. But although the theory behind them looks solid, there are tricky practical problems and need to be overcome.Two different approaches, based on different magnetic phenomena, are being pursued. The first, being investigated by Gary Prinz and his colleagues at the Naval Research Laboratory (NRL) in Washington, D.c), exploits the fact that the electrical resistance of some materials changes in the presence of magnetic field— a phenomenon known as magneto- resistance. For some multi-layered materials this effect is particularly powerful and is, accordingly, called “giant” magneto-resistance (GMR). Since 1997, the exploitation of GMR has made cheap multi-gigabyte hard disks commonplace. The magnetic orientations of the magnetised spots on the surface of a spinning disk are detected by measuring the changes they induce in the resistance of a tiny sensor. This technique is so sensitive that it means the spots can be made smaller and packed closer together than was previously possible, thus increasing the capacity and reducing the size and cost of a disk drive. Dr. Prinz and his colleagues are now exploiting the same phenomenon on the surface of memory chips, rather spinning disks. In a conventional memory chip, each binary digit (bit) of data is represented using a capacitor-reservoir of electrical charge that is either empty or fill -to represent a zero or a one. In the NRL’s magnetic design, by contrast, each bit is stored in a magnetic element in the form of a vertical pillar of magnetisable material. A matrix of wires passing above and below the elements allows each to be magnetised, either clockwise or anti-clockwise, to represent zero or one. Another set of wires allows current to pass through any particular element. By measuring an element’s resistance you can determine its magnetic orientation, and hence whether it is storing a zero or a one. Since the elements retain their magnetic orientation even when the power is off, the result is non-volatile memory. Unlike the elements of an electronic memory, a magnetic memory’s elements are not easily disrupted by radiation. And compared with electronic memories, whose capacitors need constant topping up, magnetic memories are simpler and consume less power. The NRL researchers plan to commercialise their device through a company called Non-V olatile Electronics, which recently began work on the necessary processing and fabrication techniques. But it will be some years before the first chips roll off the production line.Most attention in the field in focused on an alternative approach based on magnetic tunnel-junctions (MTJs), which are being investigated by researchers at chipmakers such as IBM, Motorola, Siemens and Hewlett-Packard. IBM’s research team, led by Stuart Parkin, has already created a 500-element working prototype that operates at 20 times the speed of conventional memory chips and consumes 1% of the power. Each element consists of a sandwich of two layers of magnetisable material separated by a barrier of aluminium oxide just four or five atoms thick. The polarisation of lower magnetisable layer is fixed in one direction, but that of the upper layer can be set (again, by passing a current through a matrix of control wires) either to the left or to the right, to store a zero or a one. The polarisations of the two layers are then either the same or opposite directions.Although the aluminum-oxide barrier is an electrical insulator, it is so thin that electrons are able to jump across it via a quantum-mechanical effect called tunnelling. It turns out that such tunnelling is easier when the two magnetic layers are polarised in the same direction than when they are polarised in opposite directions. So, by measuring the current that flows through the sandwich, it is possible to determine the alignment of the topmost layer, and hence whether it is storing a zero or a one.To build a full-scale memory chip based on MTJs is, however, no easy matter. According to Paulo Freitas, an expert on chip manufacturing at the Technical University of Lisbon, magnetic memory elements will have to become far smaller and more reliable than current prototypes if they are to compete with electronic memory. At the same time, they will have to be sensitive enough to respond when the appropriate wires in the control matrix are switched on, but not so sensitive that they respond when a neighbouring elements is changed. Despite these difficulties, the general consensus is that MTJs are the more promising ideas. Dr. Parkin says his group evaluated the GMR approach and decided not to pursue it, despite the fact that IBM pioneered GMR in hard disks. Dr. Prinz, however, contends that his plan will eventually offer higher storage densities and lower production costs.Not content with shaking up the multi-billion-dollar market for computer memory, some researchers have even more ambitious plans for magnetic computing. In a paper published last month in Science, Russell Cowburn and Mark Well and of Cambridge University outlined research that could form the basis of a magnetic microprocessor — a chip capable of manipulating (rather than merely storing) information magnetically. In place of conducting wires, a magnetic processor would have rows of magnetic dots, each of which could be polarised in one of two directions. Individual bits of information would travel down the rows as magnetic pulses, changing the orientation of the dots as they went. Dr. Cowbum and Dr. Welland have demonstrated how a logic gate (the basic element of a microprocessor) could work in such a scheme. In their experiment, they fed a signal in at one end of the chain of dots and used a second signal to control whether it propagated along the chain.It is, admittedly, a long way from a single logic gate to a full microprocessor, but this was true also when the transistor was first invented. Dr. Cowburn, who is now searching for backers to help commercialise the technology, says he believes it will be at least ten years before the first magnetic microprocessor is constructed. But other researchers in the field agree that such a chip, is the next logical step. Dr. Prinz says that once magnetic memory is sorted out “the target is to go after the logic circuits.” Whether all-magnetic computers will ever be able to compete with other contenders that are jostling to knock electronics off its perch — such as optical, biological and quantum computing — remains to be seen. Dr. Cowburn suggests that the future lies with hybrid machines that use different technologies. But computing with magnetism evidently has an attraction all its own.In developing magnetic memory chips to replace the electronic ones, two alternative research paths are being pursued. These are approaches based on:
 ....
MCQ-> Read the given passage carefully and select the best answer to each question out of the four given alternatives.The Divine Comedy is a narrative poem describing Dante's imaginary journey. Midway on his journey through life Dante realizes he has taken the wrong path. The Roman poet Virgil searches for the lost Dante at the request of Beatrice; he finds Dante in the woods on the evening of Good Friday in the year 1300 and serves as a guide as Dante begins his religious pilgrimage to find God. To reach his goal, Dante passes through Hell, Purgatory and Paradise. The Divine Comedy was not titled as such by Dante; his title for the work was simply Commedia or Comedy. Dante’s use of the word "comedy" is medieval by definition. To Dante and his contemporaries, the term "comedy" meant a tale with a happy ending, not a funny story as the word has since come to mean. Dante and Virgil enter the wide gates of Hell and descend through the nine circles of Hell. In each circle they see sinners being punished for their sins on earth; Dante sees the torture as Divine justice. Dante first travels through circles of hell and then through 3 rings before entering the 8th circle. Then there are 9 bowge before Dante reached the 9th circle. After 9th circle Dante has to travel 4 more regions. On Easter Sunday, Dante emerges from Hell. Through his travels, he has found his way to God and is able, once more, to look upon the stars.To reach god, Dante has to pass through which of the following?
 ....
MCQ->Pick out thể one word for - a secret arrangement....
MCQ-> Read the following passage carefully and answer the questions given at the end. The second issue I want to address is one that comes up frequently - that Indian banks should aim to become global. Most people who put forward this view have not thought through the costs and benefits analytically; they only see this as an aspiration consistent with India’s growing international profile. In its 1998 report, the Narasimham (II) Committee envisaged a three tier structure for the Indian banking sector: 3 or 4 large banks having an international presence on the top, 8-10 mid-sized banks, with a network of branches throughout the country and engaged in universal banking, in the middle, and local banks and regional rural banks operating in smaller regions forming the bottom layer. However, the Indian banking system has not consolidated in the manner envisioned by the Narasimham Committee. The current structure is that India has 81 scheduled commercial banks of which 26 are public sector banks, 21 are private sector banks and 34 are foreign banks. Even a quick review would reveal that there is no segmentation in the banking structure along the lines of Narasimham II.A natural sequel to this issue of the envisaged structure of the Indian banking system is the Reserve Bank’s position on bank consolidation. Our view on bank consolidation is that the process should be market-driven, based on profitability considerations and brought about through a process of mergers & amalgamations (M&As;). The initiative for this has to come from the boards of the banks concerned which have to make a decision based on a judgment of the synergies involved in the business models and the compatibility of the business cultures. The Reserve Bank’s role in the reorganisation of the banking system will normally be only that of a facilitator.lt should be noted though that bank consolidation through mergers is not always a totally benign option. On the positive side are a higher exposure threshold, international acceptance and recognition, improved risk management and improvement in financials due to economies of scale and scope. This can be achieved both through organic and inorganic growth. On the negative side, experience shows that consolidation would fail if there are no synergies in the business models and there is no compatibility in the business cultures and technology platforms of the merging banks.Having given that broad brush position on bank consolidation let me address two specific questions: (i) can Indian banks aspire to global size?; and (ii) should Indian banks aspire to global size? On the first question, as per the current global league tables based on the size of assets, our largest bank, the State Bank of India (SBI), together with its subsidiaries, comes in at No.74 followed by ICICI Bank at No. I45 and Bank of Baroda at 188. It is, therefore, unlikely that any of our banks will jump into the top ten of the global league even after reasonable consolidation.Then comes the next question of whether Indian banks should become global. Opinion on this is divided. Those who argue that we must go global contend that the issue is not so much the size of our banks in global rankings but of Indian banks having a strong enough, global presence. The main argument is that the increasing global size and influence of Indian corporates warrant a corresponding increase in the global footprint of Indian banks. The opposing view is that Indian banks should look inwards rather than outwards, focus their efforts on financial deepening at home rather than aspiring to global size.It is possible to take a middle path and argue that looking outwards towards increased global presence and looking inwards towards deeper financial penetration are not mutually exclusive; it should be possible to aim for both. With the onset of the global financial crisis, there has definitely been a pause to the rapid expansion overseas of our banks. Nevertheless, notwithstanding the risks involved, it will be opportune for some of our larger banks to be looking out for opportunities for consolidation both organically and inorganically. They should look out more actively in regions which hold out a promise of attractive acquisitions.The surmise, therefore, is that Indian banks should increase their global footprint opportunistically even if they do not get to the top of the league table.Identify the correct statement from the following:
 ....
MCQ-> Read the passage carefully and answer the questions givenWill a day come when India’s poor can access government services as easily as drawing cash from an ATM? . . . [N]o country in the world has made accessing education or health or policing or dispute resolution as easy as an ATM, because the nature of these activities requires individuals to use their discretion in a positive way. Technology can certainly facilitate this in a variety of ways if it is seen as one part of an overall approach, but the evidence so far in education, for instance, is that just adding computers alone doesn’t make education any better. . . . The dangerous illusion of technology is that it can create stronger, top down accountability of service providers in implementation-intensive services within existing public sector organisations. One notion is that electronic management information systems (EMIS) keep better track of inputs and those aspects of personnel that are ‘EMIS visible’ can lead to better services. A recent study examined attempts to increase attendance of Auxiliary Nurse Midwife (ANMs) at clinics in Rajasthan, which involved high-tech time clocks to monitor attendance. The study’s title says it all: Band-Aids on a Corpse . . . e-governance can be just as bad as any other governance when the real issue is people and their motivation. For services to improve, the people providing the services have to want to do a better job with the skills they have. A study of medical care in Delhi found that even though providers, in the public sector had much better skills than private sector providers their provision of care in actual practice was much worse. In implementation-intensive services the key to success is face-to-face interactions between a teacher, a nurse, a policeman, an extension agent and a citizen. This relationship is about power. Amartya Sen’s . . . report on education in West Bengal had a supremely telling anecdote in which the villagers forced the teacher to attend school, but then, when the parents went off to work, the teacher did not teach, but forced the children to massage his feet. . . . As long as the system empowers providers over citizens, technology is irrelevant. The answer to successfully providing basic services is to create systems that provide both autonomy and accountability. In basic education for instance, the answer to poor teaching is not controlling teachers more . . . The key . . . is to hire teachers who want to teach and let them teach, expressing their professionalism and vocation as a teacher through autonomy in the classroom. This autonomy has to be matched with accountability for results—not just narrowly measured through test scores, but broadly for the quality of the education they provide. A recent study in Uttar Pradesh showed that if, somehow, all civil service teachers could be replaced with contract teachers, the state could save a billion dollars a year in revenue and double student learning. Just the additional autonomy and accountability of contracts through local groups—even without complementary system changes in information and empowerment—led to that much improvement. The first step to being part of the solution is to create performance information accessible to those outside of the government. . . .According to the author, service delivery in Indian education can be improved in all of the following ways EXCEPT through:
 ....
Terms And Service:We do not guarantee the accuracy of available data ..We Provide Information On Public Data.. Please consult an expert before using this data for commercial or personal use
DMCA.com Protection Status Powered By:Omega Web Solutions
© 2002-2017 Omega Education PVT LTD...Privacy | Terms And Conditions