Analysis Of Herbert Blumer s Social Movement - 1738 Words

Herbert Blumer describes social movements as â€Å"†¦collective enterprises to establish a new order of life. They have their inception in the condition of unrest, and derive their motive power on one hand from dissatisfaction with the current form of life, and on the other hand, from wishes and hopes for a new scheme or system of living.† (Blumer, 1939, p. 199). Social groups partake in a movement in order to implement change through the use of protests and community involvement to share their goal. Particularly, participants of the LGBTQ+ (lesbian, gay, bisexual, transgender, queer, etc,) movement strive to gain equality and acceptance for people of all genders and sexual orientations in modern day society while ending discrimination against†¦show more content†¦Classical conditioning is the pairing of an unconditioned stimulus with a conditioned stimulus in order to elicit a conditioned response (Alexanderson, 2016). In the case of the LGBT+ rights movement, s upporters may learn to pair the conditioned stimulus of LGBT+ pride symbols, such as the rainbow flag, with a conditioned response of enthusiasm. For example, at the 2016 New York pride parade there were accounts of supporters donning merchandise, such as T-shirts, with the popular symbol (Wickman, 2013). When participants of the social movement attend an event such as a protest or a parade, such as the New York City Pride March, they are likely to observe the enthusiasm of the crowds around them (Levy, 2015). The enthusiasm of the crowd acts as an unconditioned stimulus that causes individual enthusiasm to increase. An individual’s predominant inclination will be enhanced in a group with similar inclinations due to the phenomenon of group polarization (Alexanderson, 2016). In this case, participants of a parade for gay pride will have enhanced enthusiasm in addition their already-present enthusiasm. When this enthusiasm is paired with an iconic gay rights symbol, such as the rainbow flag, it becomes a conditioned stimulus able to elicit a conditioned response of enthusiasm on it’s own. Since the 1970s, the rainbow flag has been symbolic of the LGBT+ movement and serves to empower and unify participants, partially because of itsShow MoreRelatedEssay about Research Methodology Report1448 Words   |  6 PagesLinguistics and Discourse Analysis, concluding as to why I have settled upon the latter in my own research. One qualitative method of research I will employ is a case study. The aim of my case study is to highlight the key components of the Riot Grrrl movement in the 90s. Thomas defines a case study as; ‘An analysis of persons, events, decisions, periods†¦ in which a study is conducted and the case is illuminated and explicated. (1) With the Riot Grrrl movement of the early 90’s providing my caseRead MoreSymbolic Interactionism George Simmel Jacqueline Low10230 Words   |  41 PagesStructure, Agency, and Social Reality in Blumerian Symbolic Interactionism: The Influence of Georg Simmel Author(s): Jacqueline Low Source: Symbolic Interaction, Vol. 31, No. 3 (Summer 2008), pp. 325-343 Published by: Wiley on behalf of the Society for the Study of Symbolic Interaction Stable URL: http://www.jstor.org/stable/10.1525/si.2008.31.3.325 . 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He was the first to suggest that deviant labeling satisfies that function and satisfies society s need to control the behavior. As a contributor to American Pragmatism and later a member of the Chicago School, George Herbert Mead posited that the self is socially constructed and reconstructed through the interactions which each person has with the community. The labeling theory suggests that people obtain labelsRead MorePost 1900 American Homelessness Essay2029 Words   |  9 Pagesfocus on post 1900. In modern society it can be inferred that economic crisis’s, institutional reintegration (mentally ill, prison system) failure, and reintegration of Veterans are primary culprits of American homelessness. Sociological Analysis Social problems are all around; they affect our daily lives and show no sign of stopping on their own. They have underlying causes that needs to be exposed to the public. For example, throwing newspaper over an unfortunate mess that the dog made onRead Morebiology 125894 Words   |  24 PagesToward a New Vision: Race, Class, and Gender as Categories of Analysis By: Patricia Hill Collins Summary- The author writes about oppression in society and how it is full of contradictions. She states that there are no pure victims or oppressors, but rather everyone experiences a different amount of penalty and privilege based on their race and social status. She believes that if women and people of colour could find that they have common grounds in regards to class, it will eliminate racismRead MoreCollective Behavior11901 Words   |  48 Pagesparticular institution such as schools, on abstract group properties such as social stratification or bureaucratic structure, or on a single social process such as socialization. To be sure many areas of sociology involve the study of behavior --but they tend to be restricted to particular types e.g., religious, criminal or political behavior. In contrast collective behavior is not restricted to a given type of behavior or social process. It is more general and inclusive. What do sociologists mean byRead MoreCollective Behavior11916 Words   |  48 Pagesparticular institution such as schools, on abstract group properties such as social stratification or bureaucratic structure, or on a single social process such as socialization. To be sure many areas of sociology involve the study of behavior --but they tend to be restricted to particular types e.g., religious, criminal or political behavior. In contrast collective behavior is not restricted to a given type of behavior or social process. It is more general and inclusive. What do sociologists mean byRead MoreSo, How Do People Really Use Their Handheld Devices? an Interactive Study of Wireless Technology Use13130 Words   |  53 Pagestechnology into their work and personal roles, and at the same time, adjusted these roles to ï ¬ t new expectations arising from the technology. Innovative ways of using the technology were shaped by individual needs as users adapted their message contexts, social etiquette, self-impressions, and ways of doing business. A need to self-regulate emerged with high expectations of availability and the blurring of multiple work and personal roles. Copyright # 2002 John Wiley Sons, Ltd. Introduction The mostRead MoreSummary Communication Theory13076 Words   |  53 Pagesand depends on the attitudes people have towards other people or things. 4) Communication is a relational process because it influences the relationship between the communicators. 5) A message in a successful communication stimulates the hearer(s) who receive it to create a response. What is a communication theory? A communication theory explains how the exchange of messages works and which factors influence the way we understand messages or rather assign meaning to them. What are the essential

1984 compared to cults Essay example - 2218 Words

nbsp;nbsp;nbsp;nbsp;nbsp;In the book 1984, written by George Orwell, there is a group portrayed that is similar to what society would call a cult. A cult is defined as a religion or religious sect generally considered to be extremist or false, with its followers often living in an unconventional manner under the guidance of an authoritarian, charismatic leader. Totalism is described as the principle of complete and unrestricted power in government. The books main themes include language as mind control and psychological and physical intimidation and manipulation. In the book, the people live in a city which is very out of the ordinary and also overseen by a charismatic leader, Big Brother. This society, portrayed by George Orwell has†¦show more content†¦Once this happens, the followers will believe anything that the party tells them, even if it makes no sense at all. In 1984, the Ministry of Peace is in charge of waging perpetual war, which is the complete opposite of what someone would think. This is what we call â€Å"doublespeak†. Doublespeak is when someone uses language that says one thing, but means the other. Most people would think the Ministry of Peace would be in charge of keeping peace between Oceania and the other countries. The Ministry of Truth was in charge of changing books to reflect the party’s ideology. If it were actually the Ministry of Truth, then it wouldn’t be feeding lies to the people of Oceania. The Ministry of Love is in charge of torturing people, which is also ironic. Winston never goes into the building until the end, when he is kept prisoner. nbsp;nbsp;nbsp;nbsp;nbsp;Just like in 1984, cults control the flow of information within their community. Milieu control is the method that they most commonly use. Basically, milieu control is the control of all communication within an environment. †In such an environment individual autonomy becomes a threat to the group. There is an attempt to manage an individuals inner communication. Milieu control is maintained and expressed by intense group process, continuous psychological pressure, and isolation by geographical distance, unavailability of transportation, or evenShow MoreRelatedThe Cult Of Fensive Essay1355 Words   |  6 Pagesthe â€Å"cult of the offensive† is militarized tendency to glorify the offensive and adopt the military strategies and accompanied the assumption of the elite civilians that have the advantage of warfare. The primary argument that Van Evera has to declare about â€Å"cult of the offensive† was the main principal cause of World War I . Van Evera states that because world power government made a wrong choice in foreign policy, it is the reason why World War I happened. He also concluded that the cult of theRead MoreInside a Totalitarian Regime: Key features of Stalinism Essay1652 Words   |  7 PagesStalin’s rule lasted almost thirty years, from the middle of the 1920’s until his death in 1953. His rule deeply transformed the USSR and destalinization is still not fully achieved today. While Stalinism and Nazism are often compared because they were the two totalitarian regimes of the 20th century, the Stalinist regime lasted for decades while Nazism collapsed after 12 years, thus raising several questions concerning the particular nature of the Stalinist Society. What were the key features ofRead MoreBrave New World And 19841150 Words   |  5 PagesWhat would our world be like if we did not have religion? Would things be better or worse? There are so many different religious groups and practices that make up the simple fibers of our existence. 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However, there are still some differencesRead MoreUpheaval and Renewal in Egypt and Syria 1585 Words   |  7 Pagesâ€Å"corrective revolution† in both countries, then the use of the party and the patronage system to ensure loyalty to the regime, the relationship with the military, and the relationship with the religious groups. Lastly the focus will be on Al-Asad’s cult of personality and the Egyptian use of elections as oppo site ways to legitimise the regime. In 1970 the new leaders in Syria and Egypt had to face the problem of gathering support from society. The Egyptian President Sadat was considered not worthyRead MoreThe Iceman At The Bolzano Museum928 Words   |  4 PagesThe Creation of New Worlds which is an general overview of the Iceman and Neolithic according to the ppt. 1994, Barry Cunliffe (ed.) authored Prehistoric Europe: An Illustrated History which is also has coverage of the Neolithic according to the ppt. 1984, Timothy Champion, Clive Gamble, Stephen Shennan, and Alasdair Whittle collectively wrote Prehistoric Europe which, again, has coverage of the Neolithic period according to the ppt. According to the documentary: Patrick Hunt (Alpine Archaeologist)Read MoreSocial Psychology : Midterm Exam Summer 20154074 Words   |  17 Pagesmay alter attitudes on the basis of quite different cognitive processes. First, explain this phenomenon and briefly describe one research study that illustrates the â€Å"two-route† idea. Explain the principles and techniques anyone would use to become a cult leader. Ajzen and Fishbein (1977) state in their article that previous studies show that there is inconsistent and disappointingly low relations between attitude and behavior. They go on to say that an individual’s attitude has a consistently strongRead MoreOlympic History : The Olympic Games1209 Words   |  5 Pagesand other religious and political practices as early as the 10th century B.C.† (Ancient Olympic Games.). This is suiting because religion and the Greek Olympics were related. â€Å"The Olympic Games were closely linked to the religious festivals of the cult of Zeus† (Ancient Olympic Games.). Though the early Olympic Games were religious, that is not the only reason why they were held. They were also held to allow athletes to show their abilities and in order to keep the relationships between Greek citiesRead MoreDifference Between Health And Social Class1333 Words   |  6 Pagesinevitable? Health and ill health on the basis of Cultural/Behaviour is explained as having direct relationships with social class and how their actions determine their health. According to (Bourdieu 1984) Life expectancy amongst people in high social class standing was because of their â€Å"inclination towards a cult of health-consciousness and their appearance of the body: the body as a thing displayed to others†¦and a high value being placed on moderate drinking and careful diet.† What Bourdeau is suggestingRead MoreThe Religion Of Shoko Asahara1765 Words   |  8 Pagesnow the cult Aleph was not the dangerous and threatening organization its image is associated to be now. In fact, there was a time where Asahara and Aum Shinrikyo members had taken up an attitude similar to that of a humble missionary. However, the Aum Shinrikyo faith, as well as Asahara, had been obsessed with some of the philosophies of the Bible, the Book of Revelation in particular, and had an unfortunate tu rnaround, which resulted in the religion’s currently bad reputation. This cult is a perfect

Woman in Black Temes free essay sample

The ghost is the main focal point of where all of the fear is stemmed, the fear is unspoken but almost a rule for the way the villagers in Crythin Gifford live their lives. For Arthur Kipps’, the fear is individual and over whelming and presents itself to him many times despite his adamant nature to forget and move on from it all, denying its value to frighten him to his core. By making everyone afraid of her the woman in black earns herself power she didn’t have when she was alive. By creating a sense of fear, Hill leaves us at her mercy; you can do almost anything with someone living in fear, Supernatural- Arthur himself is very rational and he has his mind set on all things reality and with no such idea of ghosts, thinking the villagers are backward and ignorant, but he is blissfully unaware of the secrets the old proud house has to hide. We will write a custom essay sample on Woman in Black Temes or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page His first sighting of her, the ghost, he approaches the situation with a childlike naivety and only has ‘concern for that lonely soul of a woman’. As the reader and from our interpretation of the title and knowledge of the context and background of the novel we have suspicion, and through a little bit of belief in the supernatural we can easily identify that the ‘wasted face’ and ‘thinnest layer of flesh’ shows the supernatural. A very typical image of a ghost is created because of her gothic story technique used throughout. We saw Kipps especially grow as a character from one who is sceptical to one who is undoubting of the ghost and supernatural powers contained within the house That the woman by the graves had been ghostly I now – not believed, no – knew, for certainty lay deep within me. † (pg. 97)

Why Maglev Essay Example For Students

Why Maglev Essay MagLev technology is entirely different from any form of transportation in operation today, but the basic principles that lie at the foundation are not beyond the understanding of the beginning electricity and magnetism student. It is in the application of these principles to design and optimize an actual train that things get hairy. The basic idea has been researched since the mid-sixties, but it is only now that economically feasible prototypes are being built and governments are seriously looking towards magnets to propel us into the next century. Leading the race is Germany. Their design, the Transrapid 07, is ready for commercial production. It utilizes conventional electromagnets and forces of attraction to levitate the train. A good web site to find out more about German plans for their design is http://transrapid.simplenet.com/index-e.htm The Japanese are investigating an entirely different design involving superconducting magnets to generate huge repulsive forces which levit ate the train. However, their MLU002N is still in experimental stages. For more information, check out http://www.rtri.or.jp/rd/maglev_E.html With a little stretching, the average physics student should be able to comprehend the principles of magnetic levitation and propulsion through synchronous linear motors. To facilitate the process of understanding this complex material, we suggest that the student go through this web site in order. Make sure you understand the basic physics before moving on to the page which applies these principles to magnetically levitated vehicles. We know from experiment that a moving charge exerts a force on other moving charges; we call this effect magnetism. The magnetic force is a field force, meaning that a moving charge sets up a field which in turn exerts a force on other moving charges. The field set up by a given moving charge is found to be perpendicular to its velocity, and to decay with distance from the charge: First, we will examine how magne tic fields are created, then we will calculate their magnitude and direction. We will write a custom essay on Why Maglev specifically for you for only $16.38 $13.9/page Order now Some materials can be said to be natural magnets. These magnets dont appear to have any moving charge, so how can they set up magnetic fields? The answer is found at the atomic scale:Electrons circling an atom set up small magnetic fields. In most materials, these fields are aligned in a fairly random manner, so that all of these small fields cancel each other. In a magnet, however, these fields line up to create a net magnetic dipole, so that the object sets up a magnetic field in the surrounding space. A current is a moving charge. Moving charges set up magnetic fields. Thus, a current seems the logical way to create a magnetic field. There are two basic setups which can be used for this purpose:The Biot-Savart Law: in order to find the magnetic field (denoted by the symbol B) produced by a given current distribution, we have to integrate the field at a given test point, P, due to individual current displacements, ids:The equation for the field integral turns out to be a rather complicated one, known as the Biot-Savart Law: Ampres Law: in cetain situations, this integral can be simplified by symmetry. In these situatins, we can use a more fundamental law, known as Ampres Law. This law allows the calculation of the field from the amount of current enclosed by an arbitrary closed loop:The equation for the magnetic field in such a case turns out to be:One of the two most commonly used magnetic field equations is that for a long, straight wire. This equation can be determined from Ampr es Law through the following setup:The equation is then derived as follows:A solenoid is a tightly wound coil of wire carrying a uniform current i : The field inside a solenoid is approximately as shown in the following diagram:We can calculate the field inside a solenoid with n turns per unit length using Ampres Law:We have now examined how magnetic fields are created, and how to calculate their magnitude. Next, we will examine the force felt on moving charges and currents due to magnetic fields. We know that a moving charge sets up a Magnetic Field. We also know that this field sets up a force on other moving charges. This force is perpendicular both to the magnetic field and to the velocity of the charge: Next we will determine how to calculate this force, and then examine an example of particular significance to magnetic levitation: repulsion between parallel wires. For a moving point charge, the magnetic force is proportional to both the magnetic field strength and the velocity of the charge. Furthermore, the direction of this force is perpendicular to both the velocity and the field (direction given by right-hand rule). Thus, the magnetic force is given by:For a current in a wire, the magnetic force is proportional to the current, the length of the wire, and the magnetic field strength. Direction is perpendicular to current direction and magnetic field. Thus, the magnetic force equation looks very similar to that for a moving point charge:The repulsion or attraction between two parallel wires is of particular importance to magnetic levitation. The setup is as follows:If the currents flow in the same direction (as shown), the wires attract. If the currents flow in opposite directions, the wires repel. To calculate the force of repulsion, we first calculate the field produced by wire 1:Next, we use B1 to find the force on wire 2 due to wire 1:We now know how to determine the force on a moving charge due to a magnetic field, and how to determine the force of attraction or repulsion between two currents. Next, we will examine the phenomenon of induced currents, where a changing magnetic field can produce a current. In 1831, Michael Faraday and Joseph Henry conducted similar experiments that demonstrated the following phenomena:In the above illustration, movement of a magnet through a wire loop induces a current in that wire. Reversing the direction in which the magnet travels reverses the current direction. In this experimental setup, opening or closing switch S induces a momentary current, i. The direction of i when closing the switch is opposite the direction when opening the switch. We can conclude from the previous experiments that a change in the magnetic field through a current loop produces an current in that wire. More scientifically, we say that a change in magnetic flux (field through a given area) induces a current in the loop to oppose the change in flux. Quantitatively, we find that the negative rate of change in flux is equal to the electromotive force (EMF) in the wire:For a coil of N turns, the induced EMF is the sum of the voltages from each turn:The direction of these induced currents, according to a principle known as Lenz Law, always opposes the change in magnetic flux that produced it. When a large peice of conducting material moves through a magnetic field in such a way that the magnetic flux through the material changes, currents are induced in the material:These currents, known as eddy currents , may produce desired or undesired effects, depending on the situation. Of particular interest to magnetic levitation is the magnetic force produced, which opposes motion through the magnetic field:This induced magnetic force is somewhat analgous to frictional forces: it opposes motion in or out of the magnetic field. In our example of magnetic levitation, this effect becomes significant, as we will see later. We have now examined most of the basic electro-physics involved in magnetic levitation. In the next section, we will begin applying these physics to the magnetically levitated train. A maglev train has a system designed to provide the force for levitation. Since the levitation system is separate from the propulsion system, a designer can choose from various propulsi on systems. One propulsion system uses Linear Synchronous Motors (abbreviated as LSMs). Another propulsion system uses Linear Induction Motors (abbreviated as LIMs). This page focuses on the levitation system that can be used with either type of propulsion system.. This is a cross section of the Magneplane vehicle and its guideway. This setup achieves levitation through repulsion. The propulstion system is not explicity diagrammed in this picture; however, other sources reveal that the Magneplane system uses a LIM. (Image source: page 338, Linear Motion Electromagnetic Systems.)Now we will move on to develop equations to model a simple repulsive levitation system. .u525e8053b6bf025713919b3ef613ffd8 , .u525e8053b6bf025713919b3ef613ffd8 .postImageUrl , .u525e8053b6bf025713919b3ef613ffd8 .centered-text-area { min-height: 80px; position: relative; } .u525e8053b6bf025713919b3ef613ffd8 , .u525e8053b6bf025713919b3ef613ffd8:hover , .u525e8053b6bf025713919b3ef613ffd8:visited , .u525e8053b6bf025713919b3ef613ffd8:active { border:0!important; } .u525e8053b6bf025713919b3ef613ffd8 .clearfix:after { content: ""; display: table; clear: both; } .u525e8053b6bf025713919b3ef613ffd8 { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .u525e8053b6bf025713919b3ef613ffd8:active , .u525e8053b6bf025713919b3ef613ffd8:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .u525e8053b6bf025713919b3ef613ffd8 .centered-text-area { width: 100%; position: relative ; } .u525e8053b6bf025713919b3ef613ffd8 .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .u525e8053b6bf025713919b3ef613ffd8 .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .u525e8053b6bf025713919b3ef613ffd8 .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .u525e8053b6bf025713919b3ef613ffd8:hover .ctaButton { background-color: #34495E!important; } .u525e8053b6bf025713919b3ef613ffd8 .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .u525e8053b6bf025713919b3ef613ffd8 .u525e8053b6bf025713919b3ef613ffd8-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .u525e8053b6bf025713919b3ef613ffd8:after { content: ""; display: block; clear: both; } READ: Odysseus (1054 words) EssayWe will model the levitation system using two separate coils. One coil is part of the vehicle, and carries a direct current in the counter-clockwise direction (as viewed from above the coil). The second coil is part of the track, and carries a direct current in the opposite (clockwise) direction. In practice, the currents need to be quite large to produce a force strong enough to counteract the weight of the train. The resistance of the coils is a very important factor when the cost of providing the power is considered. Smaller resistances allow for more current to be generated using less power, making the magnetic field induced stronger. For thi s reason, it is most efficient for the coils to be superconducting. However, the cost of superconducting coils and magnets is also considerable. The magnetic field strength at segment AB due the magnetic field created by segment AB isThe force on the upper wire segment AB due the field created by the lower wire segment AB:The picture below illustrates the direction of FAB, which is the green vector on the drawing labeled FB. FB is perpendicular to ray AB, and the vector B. FB is opposite in direction to Fg , and can balance out the force of gravity. Since there are four straight wires comprising each loop, there are four forces acting on the upper loop. Note that the currents in the two loops are traveling in the same direction, which provides a repulsive force. This force provides the lift, or levitating force for the vehicle. From this simple model we have explaned how levitating forces are created. We also can point out a few further considerations:? This setup only addressed the vertical forces acting on the train and assumed that the train was horizontally stable. In reality, maglev trains need some means of horizontal stabilization to keep the train on the track, in a manner of speaking. ? In many maglev systems, the coil setup isnt quite the same as our model explained. The train carries one set of coils, and the track contains a flat conducting surface. The trains coils have a current flowing, but the track conducting surface is completely passive. The moving train coils create a moving magnetic field. This changing magnetic field, or flux, induces eddy currents in the tracks conducting surface. These induced currents then act like the track coil in the model we used. With this in mind, our model is still effective for calculations. ? Our model uses several approximations to make the mathematics mor e concise. One, in our first equation, we assumed that the segment AB was an infinitely long wire. This means that the calculation for B is not exact. This page deals with the systems involved in a Maglev train that use repulsion as the means for attraction. This is a cross section the Krauss-Maffei experimental vehicle and guideway. This setup uses attractiion for levitation and a LIM for propulsion. (Image source: page 27, Linear Motion Electromagnetic Systems.)The setup for the attraction system is very similar to to the setup for the repulsion system, except that the direction of current in one of the coils is reversed, resulting in an attractive force between the coils. Also, the coils are located on an extension of the train that wraps under the track. It is important to notice that as the distance between the two coils decreases, the attractive force increases. Under certain conditions the two coils could get pulled into direct contact, eliminating the air gap between them. This would be very undesirable. Therefore engineers who design attractive levitation system must make use of a secondary system that monitors the air gap distance and can adjust the magnetic field strength appropriately. This secondary system also would make the ride more comfortable for passengers. The magnetic field strength at segment AB due the magnetic field created by segment AB isThe force on the lower wire segment AB due the field created by the upper wire segment AB:The picture below illustrates the direction of FAB, which is the green vector on the drawing labeled FB. FB is perpendicular to ray AB, and the vector B. FB is opposite in direction to Fg , and can balance out the force of gravity. Since there are four straight wires comprising each loop, there are four forces acting on the upper loop. This attractive force provides the lift, or levitating force for the vehicle. Note that the equations are exactly the same, provided that the setups are different. (That is, in the repulsive case, the vehicle coil was above the track coil. In the attractive case presented on this page, the vehicle coil is below the track coil.)Linear motors are analogous to conventional (rotary) motors. A Linear Induction Motor, or LIM, can be visualized by unrolling a conventional induction motor until it is flat. This presentation will explain the qualitative nature of the LIM, without going into the complicated mathematical and physical derivations. We will focus on a three-phase LIM. A LIM consists of two parts, a stator, and a rotor. The stator and rotor consist of magnetically permeable material such as iron. Within the stator, three wires are embedded. Each wire weaves through the stator in a special periodic pattern. In the diagram below, the wires are perpendicular to the plane of the computer screen. Each wire is connected to a sinusoidal current source. The three currents are each 120 degrees out of phase with each other. This setup is called a three-phase current source. The pattern used with a three phase current source is this: A C B A C B Each letter represents a wire. A and A represent the wire that carries current Ia. A and A carry the same current, but point in opposite directions. The same conventions apply to B, B and C, C. This configuration is very useful because it allows the stator to create a moving magnetic field. This moving magnetic field induces currents in the rotor. These induced currents, at any instaneous time, oppose the change in the magnetic field, in accordance with Faradays Law. These induced currents then interact with the moving magnetic field, resulting in a force that moves the rotor along with the moving magnetic field in the stator. LIMs have the ability to move the rotor relative to the stator without any physical contact. This drastically reduces wear and tear on the parts involved and eliminates frictional forces that cause inefficiency. LIMs have the ability to accelerate the rotor from rest up to the speed of the moving magnetic field. LSMs are structurally very similar to LIMs except for one change. The behavior of the two types of linear motors is changed significantly. Both LIMs and LSMs consist of a stator and rotor. Both have three phase currents weaving through the stator. How LSMs differ is that their rotor has two closely spaced direct current wires spaced regularly as the diagram below shows. The moving magnetic field is setup, but the induced currents setup are much smaller than in the LIM case. One reason is that the composition of the rotor may be different: it may be laminated or consist of a material of high electrical resistance. The DC currents are the important factor in LSMs. Look at the diagram below. (Note that the position of the rotor and stator are reversed. Also note the pattern of wires in the stator is A C B A C B )From Applied Electromagnetism, page 578. The force acting on the rotor DC currents due to the track flux tends to to move the rotor to the right. (This can be shown using the right hand rule involving the vertical track flux lines. The horizonal track flux lines do not contribute to the propulsion.)The position of the DC rotor currents is very important. In the diagram above, the rotor currents coming out of the paper are aligned with the leftmost stator wire that is also coming out of the page. This produces the maximum force on the rotor. Now consider what will happen after the diagrams time frame:1. the rotor will move (in relation to its acceleration and velocity) 2. the stators magnetic field will move (in relation to the frequency of the three phase currents) Now, after a small time interal, lets examine the relative positions of the rotor and stator. If the alignment is not the same as the figure, then the force on the rotor will not be the maximum. It should be clear that the Linear Synchronous Motor operates best a t its sychronous speed. Indeed, if the rotor isnt moving close to the synchronous speed, then the LSM will not move the stator at all!If the rotor is close enough to the synchronous speed, then the LSM will be able to accelerate the rotor up to the synchronous speed. .u2530c1170eb87162ef24e345593cde22 , .u2530c1170eb87162ef24e345593cde22 .postImageUrl , .u2530c1170eb87162ef24e345593cde22 .centered-text-area { min-height: 80px; position: relative; } .u2530c1170eb87162ef24e345593cde22 , .u2530c1170eb87162ef24e345593cde22:hover , .u2530c1170eb87162ef24e345593cde22:visited , .u2530c1170eb87162ef24e345593cde22:active { border:0!important; } .u2530c1170eb87162ef24e345593cde22 .clearfix:after { content: ""; display: table; clear: both; } .u2530c1170eb87162ef24e345593cde22 { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .u2530c1170eb87162ef24e345593cde22:active , .u2530c1170eb87162ef24e345593cde22:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .u2530c1170eb87162ef24e345593cde22 .centered-text-area { width: 100%; position: relative ; } .u2530c1170eb87162ef24e345593cde22 .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .u2530c1170eb87162ef24e345593cde22 .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .u2530c1170eb87162ef24e345593cde22 .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .u2530c1170eb87162ef24e345593cde22:hover .ctaButton { background-color: #34495E!important; } .u2530c1170eb87162ef24e345593cde22 .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .u2530c1170eb87162ef24e345593cde22 .u2530c1170eb87162ef24e345593cde22-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .u2530c1170eb87162ef24e345593cde22:after { content: ""; display: block; clear: both; } READ: Timeline of the Revolutionary War EssayNote: the synchronous speed of a LSM can be altered in two main ways:1. by varying the frequency of the three phase currents 2. by varying the number of wires per unit length in the stator and rotor. LSMs, like LIMs, have the ability to move the rotor relative to the stator without any physical contact. This drastically reduces mechanical wear. LSMs do NOT have the ability to accelerate the rotor from rest up to the speed of a quickly moving magnetic field. This means that Maglev trains that use LSM must either make the synchronous speed start very slowly and increase slowly or use a secondary propulsion system for acceleration. from Linear Motion Electromagnetic Systems, page 26. The basic physics of magnetic lift and electrical propulsion are the essentials behind Maglevs energy efficiency. For example, Maglev consumes per trip about one seventh of the energy used by a Boeing 737-300 for a 125-620 mile trip. In addition, Maglev operation is not dependent upon petroleum for its energy; the electrical power can be derived from other sources. The energy efficiency is due to the mechanical efficiency resulting from drastically reduced friction and less enegry lost as heat in the operation of the vehicle. High speed is an inherent characteristic of maglev. Because the operation of the vehicle occurs without physical contact, high speeds are within technological limits. Speeds up to 500 miles per hour are possible, with top speeds usually limited not by physical constraints, but rather by economic considerations. Commercial rail today usually travels at only 200 miles per hour, while Maglev promises at minimum a 300 mile per hour top speed. For short trips, Maglev is competitive with short airplane flights of up to 500 miles! Maglev could be used to effect a fully automated transport system, with goods arriving within seconds of their scheduled time. Combining the reliability and speed advantages, this looks to be a promising possibility. Because lift and guidance forces are distributed over a large area, contact stresses are at a minima. The Linear Motor allows noncontact propulsion and braking, in contrast to conventional rail where severe stresses occur from wheel/rail contact and by power transfer. A low cost maintenance program is a certain advantage associated with this technology. Drag Forces: Magnetic and AerodynamicWhen a conductor moves through a magnetic field, the changing flux induces electric currents as reviewed in the induction page of the Basic Physics section. These eddy currents then react with the magnetic field in such a way as to brake motion through the field. Due to of this phenomenon, a part of the propulsion energy is spent counteracting the drag force. As the table from Linear Motion Magnetic Systems shows, the drag force increases as the speed increases, for the most part. As a maglev gains speed, it requires more and more energy just to remain at cruising speed. In addition to the magnetic drag force, conventional aerodynamic drag is present. Although both forms of drag are undesirable in many ways, there are some ways of utlizing them to our advantage. The drag forces can help brake a maglev train quite efficiently. In the introduction, there is a photograph of a Maglev train with aerodynamic brakes extended. Technical Problems A Study in the Feasibility of the SCM The major technical barrier to the mass adoption of Maglev as a new transportation system lies in problems with the superconducting magnets (hereafter SCM) used to levitate and power the trains. To date most Maglev trains have utilized an SCM made of NbTi. The SCM develops extremely high temperatures during operation, during which it must be cooled down to four degrees Kelvin to maintain its properties. Liquid helium is usually used for this purpose. The heat side effects are unavoidable, and thus engineers have focused on the efficacy of the cooling systems rather than designing a cooler SCM. Severe difficulties lie in the storage of the helium vapor, and the reliquification of the vapor once it has absorbed the tremendous heat of the SCM. Currently, this has been the slowest front for progress in Maglev technology. The current thought is that using cryorefrigeration techniques which constantly cool the magnet without flashing the helium prove to be the most promising. By winding the coolant through tubes surrounding the magnet, an even, constant cooling process will be effected. This maglev diagram known as the LM-500-01, also from Linear Motion Magnetic Systems, page 338, shows many of the onboard systems relating to refrigerating the superconducting magnets. These techniques, available today, is limited only by its tremendous expense, which points toward a bottom line for Maglev technology. Economical considerations have historically been a huge hurdle to otherwise very promising technological advances. This certainly rings true with the SCM and Maglev. The superconducting magnets themselves cost millions, and the cooling system technologies associated with the SCMs cost millions more. While in the lab the technologies have been very interesting, the conventional systems have so far won out, merely because of costs. Essentially, we must look at the opportunity costs involved to fully come to a conclusion with regards to the efficacy of this technology. Adopting the Maglev system worldwide would have severe costs, but with a tangible payoff over the next 20 years. We would see a definite reduction in operating costs and a great leap in efficiency, but only after the initial investment in the new technology. SCMs and cooling system RD have already cost us millions even billions of dollars, yet we are not as yet ready to commit to the Maglev system. Feasibility studies con ducted by the US Department of Transportation have shown a great need for the technology, yet no group ready to invest because of the shear number of RD dollars still needed with no real examples of Maglev success in this country. Judging from the progress of other countries, it is our recommendation that the United States take steps toward a greater use of Maglev to reduce its long term public transportation problems and take advantage of the low cost operation, reliability, and energy efficiency associated with Maglev. Weve stood on the shoulders of giants, and now its time to enumerate them . . . Bibliography:ReferencesWeve stood on the shoulders of giants, and now its time to enumerate them . . . Books1. D. Halliday, R. Resnik K. Krane, Physics, vol. 2, 4th ed. John Wiley Sons Inc., 1992. 2. Liang Chi Shen and Jin Au Kong, Applied Electromagnetism, 3rd ed. PWS Publishing Company, 1995. 3. I. Boldea and S.A. Nasar, Linear Motion and Electromagnetic Systems. John Wiley Sons Inc., 1995. Web Sites? The High Speed / Automated Transportation Home Page ? The Argonne National Laboratories Home Page ? The Railway Technical Research Institute ? Magnetbahn: The Unofficial Transrapid Homepage