SUPERCONDUCTIVITY Essays - Superconductivity, Free Essays

SUPERCONDUCTIVITY Essays - Superconductivity, Free Essays SUPERCONDUCTIVITY The definition of superconductivity. Superconductivity is a phenomenon displayed by certain conductors that show no resistance to the flow of electric current. Conductors are materials in which the electron current goes through. There are 4 different kinds of conductors. Insulators, like glass or wood, have a very high resistance while semi-conductors, such as silicon, have a medium resistance. Conductors, like copper and other metals, have very low resistance, and superconductors, comprised of certain metals such as mercury and ceramics such as lanthanum-barium-copper-oxide, have no resistance. Resistance is an obstacle in the flow of electricity. Superconductors also have strong dimagnetism. In other words, they are repelled by magnetic fields. Due to these special characteristics of superconductors, no electrical energy is lost while flowing and since magnetic levitation above a superconductor is possible, new technology in the future could include high-speed trains that travel at 483 km/h (300 mph) while levitating on a cushion of air, powerful medical systems that have many more capabilities than the CAT scan, or even magnetically driven ships that get their power from the ocean itself (Gibilisco 1993, p 28). Making materials become superconductors. When superconductivity was first discovered, it was established that the compounds needed to be cooled to within several degrees Kelvin to absolute zero (zero Kelvin). Zero degrees Kelvin is the same as -460 degrees Fahrenheit and -273 degrees Celsius. The large amount of cooling was done by putting the compound in liquid helium. Helium, which is usually a gas, liquefies when its temperature drops to 4 K. Once the material had cooled to that temperature, it became a superconductor. However, using liquid helium to cool down material has been a problem. Liquid helium is very expensive, and the cooling equipment is very large (Langone 1989, p 8). In the past, there was no economic incentive to replace ordinary conductors with superconductors because the cooling costs for superconductors were so high. Scientists have tried to find ways to overcome the cooling problems, and so far they have found 2. The first is to find a way to cool the material using something less expensive and less bulky than liquid helium. The second way is to raise the temperatures that are necessary to cause superconductivity in the metals, or the critical temperatures. By combining materials into superconducting alloys, the temperature was raised slightly. By 1933, the critical temperature was at 10 K, and it wasn't until 1969 when the critical temperature was raised to 23 K and scientists tried, unsuccessfully, to raise it again. Then, in 1986, 2 IBM researchers in Zurich found a complex ceramic material that was superconducting at 30 K. After being increased to 39 K in late 1986, a critical temperature of 98 K was reported by Ching-WuChu and his research team at the University of Houston in 1987. A new coolant was then used. Liquid nitrogen liquefies at 77 K, is fairly inexpensive, and can even be carried around in a thermos (Mayo 1988, p 7). Liquid nitrogen costs about 50 cents a liter, while liquid h elium costs several dollars a liter. Thanks to this new discovery, efficient and cost-effective superconductors could be created. HISTORY OF THE SUPERCONDUCTOR Discovery. In 1911, the Dutch physicist Heike Kamerlingh Onnes discovered superconductivity while doing research on the effects of extremely cold temperatures on the properties of metals. While conducting his experiments, he discovered that mercury list all resistance to the flow of electricity when it was cooled to about 4 K. He then went on to discover superconductivity in other metals. In each case, the material had to be cooled to within several degrees Kelvin to absolute zero. To further his experiments, Onnes once put a current in a superconductor that was formed in the shape of a ring, and cooled it in liquid helium. One year after removing the source of electricity, the current was still flowing at its original strength in the superconductor (Hazen 1988, p 31). The only downside to the new finding was that scientists were unable to explain how it worked. Many scientists had theories, but it was Albert Einstein who perhaps summed it up best when he said in 1922, "With our cons iderable ignorance of complicated quantum-mechanical systems, we are far from

How to get Your CDL in Alabama, Arkansas and Mississippi

How to get Your CDL in Alabama, Arkansas and Mississippi This article is useful for anyone who wants to get a CDL in Alabama, Arkansas and Mississippi. If you want to learn about earning a CDL at other states, we have put together a comprehensive guide on how to get a commercial driver’s license in every state of the country. AlabamaBefore You Apply for Your CDL1. Get you  doctor to fill out  the current Department of Transportation Medical Examination Report (Form 649-F)2. Learn or review  the rules and regulations of commercial driving. You can study these in Alabama’s Commercial Driver License Manual.How to ApplyTake the following documents to your nearest Driver License Division office (make sure to research ahead for one that handles CDLs!):A current Alabama driver’s licenseA Social Security card or other proof of Social Security numberYour current DOT medical certificate (from above)Proof of insurance for the testing vehicle if you are taking the skills test$25 for the written test, $20 for the skills testL icense fees vary depending on your desired  class of license. Class A costs $66.25; Class B costs $56.25; Class Ccosts $36.25. If you are purchasing a CDL  or a license to operate only a school bus, the fee is $36.25.What to Expect When TestingFirst, on test day,  you will take one or more knowledge tests (which are written), depending on the license and endorsements you want.Then, if you pass the knowledge tests, you qualify to take the skills test (which is a driving test). Another option at this point is choosing to  be issued a learner’s license, which will allow you to practice driving  a rig with a licensed commercial driver in the passenger seat.When you feel   ready to take the on-road driving test, you can make another appointment at  the CDL licensing office.  The driving skills test includes: vehicle inspection (where you must  prove your vehicle’s safety and show your inspection skills), vehicle control (you will be asked to drive forward, backward, and in turns, in a small  area), and the actual driving test (this tests how well you know  Ã‚  signs, driving laws, and regulations).ArkansasBefore you take your certification exams, you must assess your driving record. If you have any serious offenses, like  DUI, you may be disqualified.The Knowledge TestsYou must pass the written knowledge test before you can take your road skills test. In order to familiarize yourself with the content of the exam, study the Arkansas  CDL Manual  to learn about driver safety, cargo safety, equipment, traffic rules, inspection procedures, and hazardous materials.To bring on test day:Documents that prove your age and identity$42, which is the fee for your CDLIf you haul hazardous materials, you will need to have federal  background and fingerprint check.The Road Skills TestAfter you have passed the written tests, you are ready for the road skills test.  On this test, you will be asked to perform driver tasks including pre-t rip inspections, changing lanes, tying down cargo, and maneuvering intersections.  The Arkansas CDL Manual review everything you will be tested on- review the criteria before test day so you are familiar with the tasks you will face.RequirementsYou must self-certify one of the following driving categories with the Arkansas DMV:Non-Excepted InterstateExcepted InterstateNon-Excepted IntrastateExcepted IntrastateIf you choose Non-Excepted Interstate, you must provide the DMV with a federal medical certificate.MississippiTo obtain a CDL in Mississippi, you must hold a  Regular Class R driver’s license. You must also obtain a current medical card when applying.Testing for the CDLNext stop is to take and pass the written and skills tests. All the information you need to know about the exam is in the Professional Driver’s Manual, which you can find at any  driver’s license office  throughout the state. You can schedule an appointment for the driving test either   online  or by phone.What You Must BringYour valid Mississippi driver’s license, a CDL learner’s permit, and your completed application for your desired CDLAnother driver to accompany you who holds the same class CDL license (or greater) as the one you seekA current medical cardThe same class of vehicle you will be driving once you obtain your CDL (it must pass inspection before any tests will be administered)A Social Security cardProof of residency (electric or water bill, lease agreement, vehicle-registration receipt, mortgage documents, homestead exemption receipt, bank statement, notarized employer verification on company letterhead (with a phone number) that states your address)Appropriate feesOut-of-state applicants applying for a Mississippi CDL can use their valid driver’s license from another stateNote: If your job entails hauling hazardous materials, you must undergo a background check. You will have to complete a  Driver’s License Hazard ous Materials Endorsement Application  and pay a fee.

Wotif.com Case Study Example | Topics and Well Written Essays - 1000 words

Wotif.com - Case Study Example Having established a good name and profitable business operation in Australia, Wotif.com's logical choice for expansion is its neighboring country New Zealand. The proximity of the nations is considered very strategic because the target markets are the almost alike or the same. And since buyers are almost always looking at the proximity of these countries, they somehow consider buying from one or the other. Another is that since Wotif.com is very near New Zealand, customers who are aware of its services in Australia, most could also be aware of them in their neighboring country. Venturing in farther and highly unknown markets like North America, Western Europe or China did not become an option as these markets are already controlled by other huge players. The great distance and different consumer culture will also post additional challenges. In the merchant model, the companies buy the properties like hotels and others at a wholesale price, charge a sensible markup and sell them to customers. However, in the commission based model like the one employed by Wotif.com, its responsibility is solely on the provision of a venue where buyers and sellers can transact. The prices are set by the merchants and it gets a certain percentage of the price that the properties are sold. Noting that properties are not liquid and often requires high payment prices, a company operating on commission based model is more likely to succeed as it entails less risk and is assured of commission when the merchant sells. 4. Using appropriate diagrams illustrate the supply chain for online companies such as Wotif.com, eBay, Dell Computers and Amazon.com. Identify the similarities and the differences between the business models. (8 marks) Wotif.com is the same as eBay since they create value by providing venue for buyers and sellers to transact. They both profit from having a fee to post merchandises and commission to some items. Dell is a manufacturer which distributes its products directly to customers and is employing a significantly different business model from Wotif and eBay since its sets its price. For Amazon, it functions as an online store carrying merchandises from other manufacturers. Version 2. 1. How has Wotif.com maintained its competitive advantage in the marketplace (4 Marks) Wotif.com maintained its competitive advantage in the marketplace by continuing its quest of becoming the lowest cost provider of venue for merchants and buyers of properties. Another is by safeguarding its position as the most profitable and respected business organization in the online accommodation market through strategic pricing strategy and efficient business model. 2. Why would Wotif.com choose New Zealand as their first international market when there are potentially more lucrative markets in North America, Western Europe or China (4 Marks) Wotif.com's decision of conquering its neighbor New Zealand instead of huge yet unknown markets like North America, We

A) To what extent can it be argued that a Seperation of Powers exists Essay

A) To what extent can it be argued that a Seperation of Powers exists within the British Political system B)What are the arguments for and against Britian ado - Essay Example The latter privilege allows it to acquire and dispose of land, etc., the way ordinary individuals can. In contrast to this, the powers of local authorities are very much subject to statutes and regulations. In this sense, the executive powers of the local government is limited and constrained when compared with the powers of the Crown. â€Å"The power to order and reorganize the civil service derives either from the royal prerogative or the normal powers of a body recognized by law to enter into employment relations. It is detailed by Orders in Council, but these leave much leeway to ministers. It is this `flexible friend that has been used to establish Executive Agencies in the civil service and various other innovations over the years. All of this without the need for recourse to Parliament or law.† (Oliver 1994, p.641) The executive powers of the ministers, though loosely regulated, nevertheless provide them with â€Å"powers to make contracts for the supply of goods and services to departments and the public† (Shell 1994, p.301). The last fifty years had seen moves to implement more statutory controls over the executive branch. This is because the older methods of control were inappropriate and irrelevant to the modern times. Some examples include, reduction of powers of local authorities in favor of school governors and teachers; enhancement of responsibilities of hospital managers and general practitioners within the framework of the National Health Service. Both these cases suggest a move toward decentralization of executive powers. (Oliver 1994, p.639) The independence of the judicial power was solidly established in England by the Glorious Revolution of 1688-89. Ever since, one of the implicit conditions of this outcome was that the judges should take care not to encroach on the legitimate spheres of discretion of the sovereign political authorities, Crown and Parliament. The legal control of the government is aided by the Supreme Court Act,

La-La Land American Ignorance Essay -- Argumentative Persuasive Papers

La-La Land American Ignorance So tell me. Who is the prime minister of Britain? What did Koizumi just do to his cabinet? Do you even know what country he’s from? What was the reelected chancellor of Germany’s stance in his recent political campaign? What resolution did the U.N. Security Council pass in late September? Which country stopped the shipment of five million dollars of uranium 155 miles from Iraqi borders? Can you even point out the location of Baghdad on a world map? Where is Arafat’s headquarters located? Do you even know who Arafat is? What 39-year old Asian businessman took control of North Korea’s recently opened â€Å"special economic zone?† Why is Milosevic being tried at The Hague? Do you know what these things, these people, and these events, have to do with the United States? More specifically, do you know how they might affect you? It is no surprise that many Americans cannot answer these questions. In general, most of us aren’t interested in what happens in countries on the other side of the globe. We feel apathetic even to domestic events occurring in states other than our own. But that is the problem – the American public does not recognize the most basic knowledge about the current events of the world due to lack of interest. The average adult perhaps only realizes that bin Laden and al Qaeda are hiding somewhere inside or outside Afghanistan and that Saddam Hussein may have a stockpile of weapons of mass destruction hidden somewhere in Iraq. But this is about as far as their familiarity with foreign affairs extends – they may not even be able to point out Baghdad on a map or what territory Desert Storm covered. They probably cannot even identify the events that occurred at Tora Bora... ...lling our gigantic walk-in closets with more dresses from Gucci than there are days in a year than we are with North Korea’s militarization of its economy. We want to watch action movies all day long, eat Ben and Jerry’s ice cream right out of the half-gallon bucket, drive fancy BMW sports cars, booze up on Smirnoff Ice, shoot up more heroin, pay thousands for prostitutes, gamble fortunes away at the MGM Grand in Vegas, and enjoy all the pleasures of life. We care more for that than anything else in the world. And our government responds to that. The media bows to our wishes. And we grow ever more apathetic, ignoring the world around us. Sources cited: Epstein, Edward J. News From Nowhere: Television and the News, Vintage, New York NY. 1973, pp. 16; Pearson, David. â€Å"The Media and Government Deception.† Propaganda Review. Spring 1989, pp. 6-11.

How I Think and Learn

Throughout my college years I have found what my best ways of thinking and learning are. I have tried many different methods to make sure I get the best out of learning. Now that I know what helps me concentrate I stick to that method when studying. Thinking is a complex part of me that I have difficulties in, especially when I have to make a decision. Thinking and learning are a process that has no ending, and frequently can be modified to ones potential. To learn what I am being taught, I have to rewrite and review my notes.I have difficult time memorizing my notes, so the more I review them the easier it is for me to remember the content. Also, to learn in class I have to sit in the front of class to focus on what is being taught. When it comes to study time, I like to be alone to be able to think and process what I am learning. I don’t like to have distractions at this time so, this helps me concentrate and forget about any other issues I may have. I believe that I need to improve my persona so that I can become a successful and great nurse one day. I want to improve my technical skill, according to Alfaro, this it to focus on more important things.Sometimes I dedicate more time to socializing with friends and I don’t dedicate enough assignments, which is more important. In the past, while I was taking a science course, I would spend more time going out with my friends rather than studying for upcoming quizzes or exams. I know that if I focus more on important things I will be a better student that will lead to a great nursing career. Another, skill I want to improve on is my interpersonal skill. I have a difficulty communicating with others, especially if they are older people than me.I have difficulty expressing myself to others and giving any feedback. I would like to improve this skill because I want to prepare myself to working with a large number of people, like at a hospital. I know that being part of a health care team means that worki ng as a team is important. I will work on this skill by socializing more with my fellow co workers and other people when the time is appropriate. The last skill I think is important for me to improve is my intellectual skill as well. I think that my confidence in decision making is not very high.I usually don’t go with my gut feeling. For instance, when I take a test and I’m unsure about an answer, if I have an intuition about an answer I always doubt myself and end up choosing the wrong answer. I think this skill will help me as a nurse in the future because the life of patients will rely on me, and I have to make the best decision to keep them healthy. I plan to work on this skill by trusting myself and working on myself esteem. Throughout the years that I have dedicated in college to better my education and prepare for a better future I have learned many new things about myself.I’ve found out what my styles in learning are, and what helps me learn and stay fo cus. I have been able to critically think about different situations that will impact my life and have been able to make wise decisions about my life. I am happy that there is great opportunity for improvement in myself. I am looking forward into putting to use what I have learned and happy that I’ve been thought the difference between a thinker and a critical thinker. Alfaro-Lefevre, R. (2009). Critical thinking and clinical judgement (4th ed). Philadelphia: WB Saunders

Causes of the American Revolution - Free Essay Example

Sample details Pages: 4 Words: 1071 Downloads: 5 Date added: 2019/04/26 Category History Essay Level High school Tags: American Revolution Essay Did you like this example? The American Revolution was caused by the French and Indian War, the Proclamation Line of 1763, Navigation acts, lack of colonial representation, and violent colonial resistance. Even though the French and Indian War succeeded in giving Great Britain an enormous amount of territory in North America, it was also immensely expensive. In an attempt to cover these expenses, Britains parliament decided to impose taxes on the colonists, also known as the Navigation Acts. These acts led to colonial resentment over the growing imperial rule in the colonies. Having no control over these taxes, colonists realized their lack of representation in the English Parliament and wrote to King George III, hoping to gain some say in what was imposed upon them. In response, the colonists gained more taxes and their irritation with the parliament grew. Great Britain, not wanting to provocate another war with the Indians, attempted to limit Westward expansion for colonists by passing the Proclamation Line of 1763, which stated that colonists could not settle West of the Appalachian Mountains. Tired of the repressive laws and taxes bestowed upon them, colonists began to revolt and use violence as their way of rejecting British rule. These clashes over colonial freedom led to an extensive war for independence. Don’t waste time! Our writers will create an original "Causes of the American Revolution" essay for you Create order When the war ended in 1763, Britain gained a vast amount of land for its empire after signing the Treaty of Paris. Although the war had ended, fighting with indians continued. After signing the treaty, ten thousand British troops arrived on the new frontier to defend and assuage it. The soldiers lodged themselves in the homes of many settlers, causing colonial discontent with the disruption of their homes. Along with building a vast empire and strong Navy, Britain was so high in expenses that Englands national debt doubled in amount. England decided to push the debt on the colonies in the form of many taxes and laws. Resentment among colonists grew as their expansion was limited and they were heavily taxed. After an expensive war, King George III passed the Proclamation Line of 1763 to prevent further fighting with the indians. This frontier policy forbade colonial settlement West of the Appalachian Mountains, mainly in the Ohio Valley. Many colonists disliked this policy and resented the British monarchy for it. The colonists were celebrating the opening of the frontier won after the war, and grew upset that their expansion became limited. Many colonists believed that Britain was trying to keep a tight control over the colonies by enacting this policy. Since Britain was in a massive debt and in need of cash, the expenses were pushed onto America. This led to a series of taxes imposed upon the colonists, some of which were meant to prevent smuggling. The Sugar Act of 1764 taxed many commonly used imports such as sugar, coffee, and wine. Tax collection was stringently enforced and led colonists to protest and cry no taxation without representation, because they had no say in the British policy. For the colonists, property was seen as a freedom instead of just a possession. If one had property, they could provide for themselves without relying on the government. When the security of that property was threatened due to taxes, so was the liberty that came with it. Many colonists believed that their freedom was being dealt with in this way, and protested. For example, in Massachusetts, a protest was drawn up that stated that taxes ought not to be laid without representatives of the colonists affected by them. In March, 1765, the Stamp tax became a law, forcing any formally written or printed documents to be put on singular stamped paper and distributed in America by resident agents who were on payment of the taxes. The colonists would have to pay stamp tariffs on the stages of lawsuits, almanacs, newspapers, bills and bonds, diplomas, deeds, advertisements, and even dice and cards. Regardless of size, each fee seemed to be a strike on the security of property to the colonists because they were levied without assent. With the passage of the Stamp Act, merchants of the colonies rebelled by agreeing to cease imports on all British goods unless Parliament were to repeal it. Most colonies also witnessed a pause in business due to the desire to nulli fy the act, and used nothing that required the use of stamps. TAXATION WITHOUT REPRESENTATION Most Englishmen were ineligible to vote on the acts of Parliament, either because they did not own enough property, or they lived in towns that were not allowed to send members. The Sugar Act and a newly proposed stamp tax brought forth colonial protests and objections. In an attempt to justify these new acts, Thomas Whatley, a member of the Parliament, assured the colonists that they werent unrepresented, but they instead enjoyed a virtual representation, without voting for anyone. According to Whatley, each member of Parliament represented the entire empire and not just the few electors who chose them. The colonists roundly rejected this idea of virtual representation and wanted an actual representation in Parliament. In October, 1765, nine colonies sent representatives to New York to attend the Stamp Act Congress, where they drew up a set of regulations denying the authority of taxation by Parliament. This declaration of rights and grievances was framed and then sent to King Georg e III, but despite the opposition, the Stamp Act was still enacted. The colonists were angered by the lack of representation that they had in the British government, and thus their desire for freedom was fueled. COLONIAL RESISTANCE As the colonists tried to flout the British government, they formed rebellious associations, a popular one called the Sons of Liberty in Boston, led by politician Samuel Adams. The purpose of these groups was to declare the colonial intention to resist the Stamp act to the last extremity. The colonists in these associations found themselves willing to risk their lives in rebellion to prevent the security of their property from being taken by the Parliament, in which they had no representation. In response to the Stamp Act, the Sons of Liberty hung an effigy of Andrew Oliver, who was paid to distribute stamps in Massachusetts, along with a large boot with a devil climbing out of it, to symbolize Olivers evil connection to the Stamp Act. After dusk, many furious colonists of Boston burned Olivers property, stoned his house, and beheaded the effigy. Similar riots began to break out and forced the resignations of various crown-appointed officials.