Prison Gangs in the United States Research Paper

Prison Gangs in the United States - Research Paper Example First, inmates are not to interfere with other inmates, a rule which places a premium on "minding your own business." Inmates are not to inform on one another and not to place a fellow inmate in a precarious situation. The second principle commands "don't lose your head." Inmates should control their emotions during their incarceration. Third, inmates should not exploit each other. The traditional inmate code forbids racketeering, welshing on bets, stealing from other inmates, or retracting promises. Inmates have an obligation to share any wealth which they may acquire. Fourth, inmates should not show weakness or they jeopardize their masculine image. It is very important for an inmate to maintain his masculinity. Any signs of fear or cowardice will greatly harm an inmate's reputation in the prison. Finally, "don't be a sucker," in other words, prisoners should not trust the administration. This final principle demands that inmates reject the values of society represented by prison o fficials. Guards are always considered to be wrong in any dispute with inmates. The administration must not be trusted for any reason (Sykes and Messinger, 1960, p. 7-8). Adherence to the inmate code varies greatly. While most inmates make strong verbal commitment to the code, the actual behaviors of inmates often deviate from it (Ross & Richards, 2002). The inmate code serves to lessen the pains of imprisonment by increasing solidarity among the inmates (Sykes and Messinger, 1960. p. 16). By uniting inmate society, the code lessens the sense of isolation inmates often face. An inmate follows the prescription to share wealth, he can alleviate animosity and hostility. By sharing the limited wealth offered by prison society, the potential for psychological harm can be decreased substantially (Sykes and Messinger, 1960, p. 16). The threat to an inmate's masculine self  ­image can be substantially alleviated by the requirement that inmates maintain their manhood through shows of stren gth and suppression of weakness (Sykes and Messinger, 1960. p. 17). When inmates arrive in prison they undergo prison procedures which have been likened to a series of status degradation ceremonies (Cloward, 1960; Sykes, 1958). These ceremonies convey two messages to the inmate. First, they involve the "ritual destruction of the individual's identity" (Cloward, 1960, p. 20). The individual's dignity is removed as his status is lowered. The lowering of status and stripping of dignity occurs through such procedures as strip searches, assignment of identification numbers instead of names, and the provision of uniforms, all of which create a homogenous inmate society. Second, the new identity provided to the inmate is of a lower status than their previous rank as a member of free society (Cloward, 1960, p. 20). Cloward (1960) argues that prison allows inmates to enhance their status through illegitimate means. Inmates may take on several roles in their efforts to gain status within pris on culture. They may become merchants or peddlers who specialize in providing material goods to other inmates. Politicians, or "big-shots," will control the spread of information among inmates (Cloward, 1960, p. 34). These inmates will seek positions, which grant them greater freedom of movement or greater access to prison officials, allowing them to gather information. Finally, an inmate may assume the role of "right

Why Is Credentialing Important Essay Example for Free

Why Is Credentialing Important Essay Physicians in general often undergo credentialing by the medical institutions and managed care organizations they want to work for and be affiliated with. Such organizations include hospitals, health maintenance organizations (HMOs), and preferred provider organizations (PPOs) which are responsible in providing quality services to their subscribers (Sobelman, 2001). According to Freed et al (2006, p. 913) â€Å"credentialing is a systematic approach to the collection, review, and verification of a practitioners professional qualification†. A practitioners qualification can be assessed based on his or her professional license, certification, educational background and preparation, clinical experience and professional activity and practices (Jones, nd). Credentialing therefore is important in evaluating and assessing the competence of medical practitioners. It is important to both the physicians and medical institutions because credentialing serves as the basis of maintaining quality health care and patient safety (Norcal, 1999, p. 1). Basically, credentialing is a necessity for almost every healthcare providers particularly the physicians for they are directly responsible for the patients treatment outcomes. Credentialing is an ongoing process (Rozovsky et al, 1994) that involves review and verification of the physicians current professional license, current, education, training, hospital privileges and levels of liability insurance as well as review of the physicians office if applicable to determine the quality of service the physician provide to his own clients (Sobelman, 2001). It is an ongoing and continuous process because of the need to ensure that the training and practices of the physicians are aligned with the changing needs of the patients. The processes involved in credentialing are necessary particularly the validation of certificates, training and current hospital privileges as well as the Drug Enforcement Administration and Controlled Drug Substance Certificates because these are very important in avoiding any possible risk and professional liabilities in which the managed care organizations can be held liable. Certificates in particular assured the public that the physician has successfully completed an accredited educational programs, examinations and evaluations, and provide assurance that the physician possess the skills, expertise, knowledge and experience required in practicing his profession (Hillemeier, 2004) When the physicians capability, scope of practice and specializations are known, risks and liabilities are avoided and managed. From this, it can be viewed that managed care organizations conduct credentialing of physicians as part of their risk management activities. Defining, risk management, â€Å" it is a planned and systematic process of reducing and/or eliminating the probability that losses will occur† (Yale New Haven Hospital, n. d). It is very common that when patients has complaints regarding the quality of care given to them, the hospital or HMO lose patients or subscribers that could have provided them better profitability. Complaints from patients and subscribers also pose threat as it can decrease the level of trust patients and the public have for the organization. Thus, managed care organizations see to it that the physicians who will work for them have undergone credentialing which must be designed to aid organizations in choosing competent physicians that has the capability of providing quality care for their patients. Organizations are aware that competent physicians are an important asset to the organization. On the part of the physicians themselves, credentialing broadens the scope of their practice. The more the credentials a physician holds, the more clinical activities he will be authorized to perform. Therefore credentialing is a process that benefits both the organization and the physicians as well as the public. Because of credentialing, physicians and organizations have aimed to improve the competence and quality of healthcare services they offer and provide. Credentialing raises the standards of healthcare organizations. References: Freed, G. , Singer, D. , Lakhani, I. , et al (2006) Use of Board Certification and Recertification of Pediatricians in Health Plan Credentialing Policies, The Journal of American Medical Association, 295:913-918 Hillemeier A, (2004). Recertification now requires a secure examination. Journal of Pediatr Gastroenterol Nutr. ,38:376-377 Jones, Dolores, Reimbursement, Privileging, and Credentialing for Pediatric Nurse Practitioners, Retrieved online on February 24, 2007 www.medscape.com/

Effects of Moderate Alcohol Consumption on Oxidative Stress

Effects of Moderate Alcohol Consumption on Oxidative Stress Abstract Oxidative stress is implicated in the pathogenesis of atherosclerosis and myocardial infarction. Moderate alcohol consumption has various favourable metabolic changes. In this study Malondialdehyde (MDA) levels and activities of enzymatic antioxidants namely superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were determined in 120 non smoker healthy males with self reported daily consumption of 90ml or 120ml of whisky and rum. 30 non smoker healthy males with no history of alcohol consumption were taken as controls. The result shows significantly elevated levels of MDA (p

Priotities of Gene Therapy Essay -- Genetics Science Medicine Papers

Priotities of Gene Therapy Gene therapy is a relatively new area of medicine that attempts to apply recent advances in molecular biology, genetics and biotechnology to the treatment of human diseases. Gene therapy uses a set of approaches to the treatment of human disease based on the transfer of genetic material (DNA) into an individual. Gene delivery can be achieved either by direct administration of gene-containing viruses or DNA to blood or tissues, or indirectly through the introduction of cells manipulated in the laboratory to harbor foreign DNA. As a sophisticated extension of conventional medical therapy, gene therapy attempts to treat disease in an individual patient by the administration of DNA rather than a drug. (1) Genetic manipulations, such as replacing defective or missing genes with healthy ones, can be used to alter germ cells (egg or sperm) and somatic cells. Theoretically germ-line gene therapy appears to have more advantages since it aims at preventing a genetic defect from being transmitted to future generations. However, the prospects of germ-line gene therapy look more remote due to many unresolved ethical and social problems as well as technical obstacles. (2) What is presently understood as gene therapy is, mostly, somatic cell gene therapy. By altering the genetic material of somatic cells onetime cures of devastating, inherited disorders may be potentially achieved. But, "in principle, gene therapy should be applicable to many diseases for which current therapeutic approaches are ineffective or where the prospects of effective treatment appear exceedingly low." (1) However, gene therapy is still extremely new and highly experimental. The number of approved clinical trials is smal l, and relativ... ...scarbamylase deficiency. Hum Gene Ther 10(14):2419-37. 5. Lehrman, S. 1999. Virus treatment questioned after gene therapy death. Nature 401(6753):517-8. 6. Federico M. 1999. Lentiviruses as gene delivery vectors. Curr Opin Biotechnol 10(5):448-453. 7. Iwakuma, T, Y. Cui, L.J. Chang. 1999. Self-inactivating lentiviral vectors with U3 and U5 modifications. Virology 15;261(1):120-32. 8. Ropert, C. 1999. Liposomes as a gene delivery system. Braz J Med Biol Res;32(2):163-9. 9. Lanzov, V.A. 1999. Gene Targeting for Gene Therapy: Prospects. Mol Genet Metab 68(2):276-282. 10. Kren, B.T., R. Metz, R. Kumar, C.J. Steer .1999.Gene repair using chimeric RNA/DNA oligonucleotides. Semin Liver Dis 19(1):93-104. 11. Zanjani, D., W. French Anderson.1999. Prospects for in Utero Human Gene Therapy. Science 285(5436) p.2084-8. 12. New York Times, August 4, 1998.

Ai Weiwei: More Than Just an Artist

From the Sichuan earthquake To art and twitter: Ai Weiwei, more than just an artist 1 Table of Contents Introduction: the Sichuan Earthquake †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. 3 Ai Weiwei’s Communication Tools †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. 3 â€Å"Remembering† †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. 4 Twitter †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢ € ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. Going Local to Global †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. 5 Conclusion †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. 5 2 Introduction: the Sichuan Earthquake On the 12th may 2008 in the Sichuan province, a devastating earthquake with a magnitude of 8 on Richter’s scale occurs during the afternoon (Fawu Wang, 2009). According to an official report, 69’197 people were killed, 374’176 injured and 4. 8 Million were left homeless. Although earthquake predictions remain in a certain way always random, a scientist named Chen Xuezhong brought in 2002 evidence of a potential coming earthquake in the region (Zhiyue, 2010). It stresses that China’s government was warned of a potential coming disaster. After this short introduction, this essay will focus on the repercussions of this incident, in China as well as internationally, emphasised by Ai Weiwei’s actions through, on one hand art and on the other Internet, respectively twitter. Ai Weiwei’s Communication ToolsThe Sichuan earthquake raised strong criticism against the Chinese government, especially because of the huge number of victims among children. According to a construction engineer who published the Chinese book â€Å"Book Blade†: â€Å"School construction in China is the worst† (Li, 2008). Indeed, they are often called â€Å"tofu construction†. Several reasons cover this problematic. Among them, the tiny budgets in poor areas. This is why we find infrastructure deficits in those regions (Li, 2008). Indeed this event has raised interest and the one of a particularly renowned artist, named Ai Weiwei.In his documentary â€Å"Never sorry† Ai Weiwei explains he pursued an independent personal investigation on this accident; he wanted to find out how many children had been killed and wanted to sue the government for their deaths, because according to him, it didn’t face its responsibilities. Furthermore he reveals the difficulties encountered, due to the government’s restricted information policy, to obtain the official number of children victims (Klayman, 2012). Thus, supported by helpless parents, depressed because of their loss, he gathered the names of an important number of children killed so that they could be remembered (Helmhirst, 2012). â€Å"Remembering† Ai Weiwei is an international renowned artist with strong beliefs and personal views. As a matter of fact, he likes to use his world reputation to make the public opinion aware of the problems the Chinese population is facing because of the communist party and has always been a great defender of their rights. The Sichuan earthquake would have been hidden and forgotten in the government’s propaganda, but thanks to him and to his art creation, those students’ life will never be forgotten. Remembering† is a piece of art created by Ai Weiwei on the wall of the â€Å"Haus der Kunst† in Munich. Made with 9’000 schoolbags (McMahon, 2010), it symbolises the life of the students who died during the 2008 earthquake in Sichuan. Different colours have been chosen to decorate the schoolbags, in order to read the following phrase, written with Chinese characters, on the wall of the â€Å"Haus der Kunst†: â€Å"She lived happily for seven years in this world† (Branigan, 2011).This sentence, pronounced by the poor mother of a victim, shows how sad and tra gic this accident has been. Through this artistic work and its exposition in a cultural centre like Munich, Ai Weiwei has been able to export local Chinese problems to the rest of the world and make us aware of the repressed liberty of expression and the lack of assistance to the population in China Province, especially when it comes to people living in poor areas. In addition it expresses Ai Weiwei’s beliefs by showing us that he holds the government responsible for those high casualties.Twitter Ai Weiwei uses twitter and Internet to share his views and assess his notoriety. This tool became an essential part of Ai Weiwei’s style of communication. During the Sichuan earthquake, twitter has been used to make the people aware of the damages caused and to reveal whom Ai Weiwei holds responsible for this incident. People outside China could be informed. On the opposite, people living in the mainland of China have a restricted access to Internet, respectively twitter.Still , there are some ways to deviate from the, imposed by government, restricted freedom of speech; although the use of Internet is limited, some people in China use a VPN located outside of China to communicate within the mainland (A digital rallying cry, 2011). Thus the government’s politic, this doesn’t 4 bother Ai Weiwei who’s an active twitter user, sharing his thoughts almost daily (Twitter Ai Weiwei). As a precursor of twitter in China, Ai Weiwei considerably influenced the style of communication and the liberty of expression of Chinese people.Effectively, the following example highlights clearly those facts: when Ai Weiwei was in detention, a lot of his followers shared twitts almost every day for his liberation and manifested in the streets with the famous slogan: â€Å"Free Ai Weiwei† (Twitter Free Ai Weiwei). This shows the considerable impact he has on Chinese society. Going Local to Global The repercussions of the Sichuan earthquake can be charac terised by the influence of the western culture on the Chinese population through Ai Weiwei, respectively art and twitter.As a matter of fact Ai Weiwei has studied art both in Beijing and in New York (Wines, 2009); this certainly allowed him to draw comparisons between the Occidental and the Asian culture and to figure out which changes were to be made in the Chinese politics, for example regarding the freedom of speech. Indeed from a local incident and thanks to an international renowned artist, a positive anger in the Chinese population, against the government, has raised to fight for their rights and to freely express their opinions.Effectively, it is to be underlined that the use of twitter by the Chinese population is a relevant example for this characterisation. Conclusion In the light of these factors the Sichuan earthquake emphasises the infrastructure deficit the country is facing in Province and more importantly in poor areas. Secondly, â€Å"Remembering† is the sym bol of the anger and the sadness Ai Weiwei and the parents face regarding respectively the government and this tragic accident. Thirdly, twitter highlights a communication tool, which can easily and instantly be used. Ai Weiwei hrough a combination of these tools positively influenced the Chinese people. Although it may seem somehow utopic, Ai Weiwei with â€Å"Remembering† and twitter made a huge step forward, by making a population aware    5 how to use their rights, in the fight he struggles with the government of mainland China. Hereby, I declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work. 6 7 Ai Weiwei: More Than Just an Artist From the Sichuan earthquake To art and twitter: Ai Weiwei, more than just an artist 1 Table of Contents Introduction: the Sichuan Earthquake †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. 3 Ai Weiwei’s Communication Tools †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. 3 â€Å"Remembering† †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. 4 Twitter †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢ € ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. Going Local to Global †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. 5 Conclusion †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. 5 2 Introduction: the Sichuan Earthquake On the 12th may 2008 in the Sichuan province, a devastating earthquake with a magnitude of 8 on Richter’s scale occurs during the afternoon (Fawu Wang, 2009). According to an official report, 69’197 people were killed, 374’176 injured and 4. 8 Million were left homeless. Although earthquake predictions remain in a certain way always random, a scientist named Chen Xuezhong brought in 2002 evidence of a potential coming earthquake in the region (Zhiyue, 2010). It stresses that China’s government was warned of a potential coming disaster. After this short introduction, this essay will focus on the repercussions of this incident, in China as well as internationally, emphasised by Ai Weiwei’s actions through, on one hand art and on the other Internet, respectively twitter. Ai Weiwei’s Communication ToolsThe Sichuan earthquake raised strong criticism against the Chinese government, especially because of the huge number of victims among children. According to a construction engineer who published the Chinese book â€Å"Book Blade†: â€Å"School construction in China is the worst† (Li, 2008). Indeed, they are often called â€Å"tofu construction†. Several reasons cover this problematic. Among them, the tiny budgets in poor areas. This is why we find infrastructure deficits in those regions (Li, 2008). Indeed this event has raised interest and the one of a particularly renowned artist, named Ai Weiwei.In his documentary â€Å"Never sorry† Ai Weiwei explains he pursued an independent personal investigation on this accident; he wanted to find out how many children had been killed and wanted to sue the government for their deaths, because according to him, it didn’t face its responsibilities. Furthermore he reveals the difficulties encountered, due to the government’s restricted information policy, to obtain the official number of children victims (Klayman, 2012). Thus, supported by helpless parents, depressed because of their loss, he gathered the names of an important number of children killed so that they could be remembered (Helmhirst, 2012). â€Å"Remembering† Ai Weiwei is an international renowned artist with strong beliefs and personal views. As a matter of fact, he likes to use his world reputation to make the public opinion aware of the problems the Chinese population is facing because of the communist party and has always been a great defender of their rights. The Sichuan earthquake would have been hidden and forgotten in the government’s propaganda, but thanks to him and to his art creation, those students’ life will never be forgotten. Remembering† is a piece of art created by Ai Weiwei on the wall of the â€Å"Haus der Kunst† in Munich. Made with 9’000 schoolbags (McMahon, 2010), it symbolises the life of the students who died during the 2008 earthquake in Sichuan. Different colours have been chosen to decorate the schoolbags, in order to read the following phrase, written with Chinese characters, on the wall of the â€Å"Haus der Kunst†: â€Å"She lived happily for seven years in this world† (Branigan, 2011).This sentence, pronounced by the poor mother of a victim, shows how sad and tra gic this accident has been. Through this artistic work and its exposition in a cultural centre like Munich, Ai Weiwei has been able to export local Chinese problems to the rest of the world and make us aware of the repressed liberty of expression and the lack of assistance to the population in China Province, especially when it comes to people living in poor areas. In addition it expresses Ai Weiwei’s beliefs by showing us that he holds the government responsible for those high casualties.Twitter Ai Weiwei uses twitter and Internet to share his views and assess his notoriety. This tool became an essential part of Ai Weiwei’s style of communication. During the Sichuan earthquake, twitter has been used to make the people aware of the damages caused and to reveal whom Ai Weiwei holds responsible for this incident. People outside China could be informed. On the opposite, people living in the mainland of China have a restricted access to Internet, respectively twitter.Still , there are some ways to deviate from the, imposed by government, restricted freedom of speech; although the use of Internet is limited, some people in China use a VPN located outside of China to communicate within the mainland (A digital rallying cry, 2011). Thus the government’s politic, this doesn’t 4 bother Ai Weiwei who’s an active twitter user, sharing his thoughts almost daily (Twitter Ai Weiwei). As a precursor of twitter in China, Ai Weiwei considerably influenced the style of communication and the liberty of expression of Chinese people.Effectively, the following example highlights clearly those facts: when Ai Weiwei was in detention, a lot of his followers shared twitts almost every day for his liberation and manifested in the streets with the famous slogan: â€Å"Free Ai Weiwei† (Twitter Free Ai Weiwei). This shows the considerable impact he has on Chinese society. Going Local to Global The repercussions of the Sichuan earthquake can be charac terised by the influence of the western culture on the Chinese population through Ai Weiwei, respectively art and twitter.As a matter of fact Ai Weiwei has studied art both in Beijing and in New York (Wines, 2009); this certainly allowed him to draw comparisons between the Occidental and the Asian culture and to figure out which changes were to be made in the Chinese politics, for example regarding the freedom of speech. Indeed from a local incident and thanks to an international renowned artist, a positive anger in the Chinese population, against the government, has raised to fight for their rights and to freely express their opinions.Effectively, it is to be underlined that the use of twitter by the Chinese population is a relevant example for this characterisation. Conclusion In the light of these factors the Sichuan earthquake emphasises the infrastructure deficit the country is facing in Province and more importantly in poor areas. Secondly, â€Å"Remembering† is the sym bol of the anger and the sadness Ai Weiwei and the parents face regarding respectively the government and this tragic accident. Thirdly, twitter highlights a communication tool, which can easily and instantly be used. Ai Weiwei hrough a combination of these tools positively influenced the Chinese people. Although it may seem somehow utopic, Ai Weiwei with â€Å"Remembering† and twitter made a huge step forward, by making a population aware    5 how to use their rights, in the fight he struggles with the government of mainland China. Hereby, I declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work. 6 7

How to Use the Spanish Word Como

How to Use the Spanish Word Como Como is a common and useful word in Spanish that is frequently used to compare two things, persons, or actions that are similar. Como Often Equivalent to Like or As Como is frequently used as a preposition or conjunction that means like or as. Regardless of which of the two parts of speech it is used as, it is generally understood much the same way by English speakers, so this introductory lesson will look at examples of its usage as both parts of speech together. (Note: English translations used in this lesson reflect English as it is frequently spoken rather than distinguishing among proper uses of like and as.) Como nearly always means something similar to in the manner of and/or is used to make actual or implied comparisons: Piense como un millonario. (Think like a millionaire.)Dice que usa las redes sociales como un presidente moderno. (He says he uses social networks like a modern president.)Si se parece a un pato, anda como un pato y grazna como un pato, entonces es un pato. (If it seems like a duck, walks like a duck, and quacks like a duck, then its a duck.)Te quiero, pero como amigo. (I love you, but as a friend.)No hay nadie como Francisco. (There is nobody like Francisco.) ¡No me trates como un perro! (Dont treat me like a dog!)Como tu profesor, quiero ayudarte y ser tu amiga. (As your teacher, I want to help you and be your friend.)No duermo como antes. (I dont sleep like I did before.)He decidido vestirme como quiero. (I have decided to dress myself the way I want.)Te odio como jams he odiado a nadie. (I hate you like Ive never hated anyone before.)Como era de esperar, la pelà ­cula ha batido todos los rà ©cords. (As expected, the film has broken all records.)Mà ­rame como si fuera la prim era vez. (Look at me as if it were the first time.) Salieron como si nada hubiera pasado. (They left as if nothing had happened.)El cine se lo conoce como el sà ©ptimo arte. (Cinema is known as the seventh art.)Quiero la piel como estaba antes. (I want my skin to like it was before.) Como the conjunction/preposition should not be confused with the homonym como, the first-person singular indicative form of comer that means I eat. Como in Approximations Colloquially, como is sometimes used for approximations. Typical translations include about and approximately. Tengo un primo que pesa como 200 kilogramos. (I have a cousin who weighs approximately 200 kilograms.)Maneje como dos millas pasando la gasolinera Texaco. (Drive about two miles, passing the Texaco gas station.)Al final me costà ³ como mil dà ³lares tomar el examen. (In the end, it cost me something like $1,000 to take the text.)Llevo como dos semanas intentando comprar los boletos en là ­nea para el concierto. (I spent about two weeks trying to buy the tickets online for the concert.) Using Como for How With an orthographic accent, cà ³mo becomes an adverb and is often translated as how. This occurs most often in questions and indirect questions:  ¿Cà ³mo ests? (How are you?) ¿Cà ³mo puedo adquirir un pasaporte? (How can I get a passport?) ¿Cà ³mo puede algo tan pequeà ±o hacerte sentir tan grande? (How can something so small make you feel so great?)No sà © cà ³mo bajar los fotos del servidor. (I dont know how to download the photos from the server. Note: This is an example of cà ³mo being used in an indirect question.)No me importa cà ³mo lo haces. (It doesnt matter to me how you do it.)

Free Essays on People Make History

In one of his quotes, Dr. William Clyde de Vane states â€Å"one of these things is the capacity for greatness in man- his capacity for being often the master of the event - and sometimes even more- the changer of the course of history itself.† I agree with this quote that people do make history and people can change history. People throughout that past of changed to course of history and people will continue to make history as time progress on forever and ever. In Charles Dickens novel Tale of Two Cities, we see how people make history. One major factor in how this takes place is the mob action describe by Dickens during the French Revolution and during The Terror of 1792-1794. These specific events in history were basically the cause and effect of people. The cause; rich aristocrats who didn’t’ care about the mass in general, as long as the rich were happy the poor could starve and die for all they cared. The effect; the poor, revolted and took things into their own hands. Mob mentality took over and history was made in the hands of the poor, better yet in the hands of men. But what does it take for a mob to become strong and have the strength to change and make history? In answer to that a mob needs a strong man. One person to defy the monarchy and take things into their own hands. When people see this, this drives them to do what others are doing. The whole thing with a mob is that if everyone is doing it then no one could get into trouble. Dickens describes this mob mentality during many scenes in his book but one scene that sticks out in my mind is where the mob storms the Bastille. Thousands of people are slaughtered at the hands of men and if it weren’t for the voices of few, no one would have had the courage to do that. By choosing to take part in these frivolous activities, people made history and throughout these revolutions continued down this path, making history. Another argument of how people ma... Free Essays on People Make History Free Essays on People Make History In one of his quotes, Dr. William Clyde de Vane states â€Å"one of these things is the capacity for greatness in man- his capacity for being often the master of the event - and sometimes even more- the changer of the course of history itself.† I agree with this quote that people do make history and people can change history. People throughout that past of changed to course of history and people will continue to make history as time progress on forever and ever. In Charles Dickens novel Tale of Two Cities, we see how people make history. One major factor in how this takes place is the mob action describe by Dickens during the French Revolution and during The Terror of 1792-1794. These specific events in history were basically the cause and effect of people. The cause; rich aristocrats who didn’t’ care about the mass in general, as long as the rich were happy the poor could starve and die for all they cared. The effect; the poor, revolted and took things into their own hands. Mob mentality took over and history was made in the hands of the poor, better yet in the hands of men. But what does it take for a mob to become strong and have the strength to change and make history? In answer to that a mob needs a strong man. One person to defy the monarchy and take things into their own hands. When people see this, this drives them to do what others are doing. The whole thing with a mob is that if everyone is doing it then no one could get into trouble. Dickens describes this mob mentality during many scenes in his book but one scene that sticks out in my mind is where the mob storms the Bastille. Thousands of people are slaughtered at the hands of men and if it weren’t for the voices of few, no one would have had the courage to do that. By choosing to take part in these frivolous activities, people made history and throughout these revolutions continued down this path, making history. Another argument of how people ma...

Intelligence Testing for Special Education

Intelligence Testing for Special Education Individualized intelligence tests are usually part of the battery of tests a school psychologist will use to evaluate students when referred for evaluation. Intelligence Testing The two most commonly used are the WISC (Wechsler Intelligence Scale for Children) and the Stanford-Binet. For many years the WISC has been considered the most valid measure of intelligence because it had both language and symbol based items and performance-based items. The WISC also provided diagnostic information, because the verbal part of the test could be compared to the performance items, to show a disparity between language and spatial intelligence. The Stanford Binet-Intelligence Scale, originally the Binet-Simon Test, was designed to identify students with cognitive disabilities. The scales focus on language narrowed the definition of intelligence, which has been to some extent broadened in the most recent form, the SB5. Both the Stanford-Binet and WISC are normed, comparing samples from each age group. In both cases, we have seen intelligence scores going up.  Research shows the mean increasing somewhere between 3 and 5 percent a decade.  Ã‚  It is believed the fact that the way instruction is mediated is directly related to how intelligence is measured.  We dont necessarily teach to the test so much as structure information that way the test scores.  It also means that children with severe apraxia or language difficulties because of autism may score very poorly on the Standford-Binet because of its focus on language.  They may have intellectually disabled or retarded in their diagnosis, whereas, in reality, they may really be Intellectually different, since their intelligence is not truly being evaluated. The Reynolds Intellectual Assessment Scales, or RAIS, takes 35 minutes to administer and covers 2 verbal intelligence indexes, 2 non-verbal indexes and a comprehensive intelligence index, which measures reasoning ability and the ability to learn, among other cognitive skills. Best Known Intelligence Test The best-known product of Intelligence testing is the IQ, or Intelligence Quotient. An IQ score of 100 is meant to reflect the average (mean) score for children the same age as the child being tested. A score over 100 implies better than average intelligence, and scores below 100 (actually, 90) implies some level of cognitive difference. Group Tests Group Tests prefer to bill themselves as ability rather than intelligence tests and are usually used to identify children for gifted programs.  These are generally used for screening to identify children with either high or low intelligence.  Children who are identified for gifted programs or IEPs are often re-tested with an individual test, either the WISC or Standford Binet intelligence tests, to have a clearer picture of a childs challenges or gifts.   The CogAT or Cognitive Abilities Test consists of several sessions, from 30 minutes (kindergarten) to 60 minutes (higher levels.) The MAB or Multidimensional Aptitude Battery consists of 10 subtests scores and can be grouped in verbal and performance areas. The MAB can be administered to individuals, groups, or on the computer. It yields standard scores, percentiles or IQs. With the emphasis on state assessments and achievement, few districts are regularly administering group tests. Psychologists usually prefer one of the individual tests of intelligence to identify children for special education services.

Political Communication in the Electronic Age Essay

Political Communication in the Electronic Age - Essay Example Few people write letters or read the newspapers anymore as these are seemingly archaic methods of communication and have the added disadvantage of costing money, regardless of how little this sum might actually be.   â€Å"Nowadays, we think nothing of emailing our aunts in Germany and getting an answer back within minutes, or seeing the latest streaming video full of up to the minute news† (Boswell, 2006).   Neither letter-writing nor newspaper delivery can provide the instant information that is today essential for businesses in the modern world to compete effectively and simply a fact of life that is taken for granted for most in the developed world.   This fact alone has changed the way in which the politicians of the world must reach out to their constituency if they expect to gain support.   People, the public at large as well as politicians, are now turning to alternative forms of receiving information, such as blogs, video blogs, webcasts, chatrooms and listser vs.   However, this introduces new challenges in determining just how to determine credible sources from noncredible and just how far the internet should be allowed to go in terms of free speech and expression.   Decency, censorship, free speech, ethicsOne of the controversial aspects of the internet and instant posting is that the internet provides a means of gathering news that has not necessarily been filtered through the many regulations and restrictions imposed by national or state boundaries.   This is primarily due to the fact that the internet itself is not regulated.

Final Assignment Example | Topics and Well Written Essays - 1500 words - 1

Final - Assignment Example Scientists are putting their best effort to install in these machines, the human like features like reasoning, intelligence, emotions and so on. If a real breakthrough is accomplished, then robots will become better performers than humans – by virtue of their being machines. Robots are speedy and accurate. They can be used in carrying out difficult tasks like welding of machines in a high temperature environment. They do not get tired or stop to eat or require a break and most interesting of all to the modern manager, robots do not complain. Such features could lead to adoption of the robot-worker, replacing human labor. This contributes to social injustice. Humans will be having their robot colleagues in the work place and whether the two will complement or compete with each other is still uncertain (Rooksby). On March 13, 2004, the Defense Advanced Research Projects Agency (DARPA), which is a small branch of the department of defense in the U.S and has the responsibility of developing the technology of the military celebrating its 10th anniversary of the DARPA Grand Challenge. 15 self-driving cars were involved in the exercise in which the robotic drivers sped through a 142-mile course between Barstow, California and Prim, Nev. The ensuing developments accelerated the development of autonomous vehicles that, according to the agency officials, could be very instrumental in doing cargo supplies and other military supplies to areas of combat without putting the lives of the human drivers in danger. Such technological inventions have promoted human justice by protecting their lives in time of war. Despite such advancements military armaments that are as a result of technology has caused lots of death and loss of earth around the globe. The use of atomic and nuclear bombs, machine guns and ot her weapons of mass destruction have led to many

Difference between intelligent and wisdom Essay Example | Topics and Well Written Essays - 750 words

Difference between intelligent and wisdom - Essay Example The need to find the truth behind the functioning of different world phenomena and nature makes knowledge equally necessary for humankind. Knowledge, from the philosophical standpoint, may include that which emanates from an individual’s intellect or possession of wisdom. The debate on the distinctions that exist between intellect and wisdom attracts the consideration of several philosophical concepts. From a philosophical perspective, it is incontrovertible that both intelligence and wisdom constitute knowledge. This brings the question of how knowledge based on intelligence differs from that with a foundation on wisdom. Many philosophical attributes to intelligence relate it to the ability to embrace rational reasoning. Rationality, as pertains to reasoning, involves individuality of thought and reasoning. Knowledge gained through experience after an expansive span of time would bring wisdom. Lifelong education coupled with the various instances, through which one acquires k nowledge, are avenues that contribute to the acquisition of wisdom that individual posses. However, there is difference between information acquisition over a long time and the level of an individual’s wisdom. ... Wise individuals tend to concentrate on the desire and enthusiasm of redefining old truths and philosophical perspectives and ideas that may present confusing and divergent opinions. Wisdom, therefore, is a basis on which there is the gain of a deep understanding of ideas beyond existing theories. Generally, this comes with high advancement in an individual’s age. The relation of redefinition of phenomena to old age emanates from the necessity to relate past events to present situations. This renders the elderly part of the population well advanced, in age, to relate events over time. The various concerns that wisdom explore include the search for humanity and morality in the society. Knowledge of intellects and the wise may also differ in their forms of approach. An intellect would acquire knowledge through scientific means that are explainable in a way that detaches the individual from the context in study. It is purely abstract an explained through theoretical points of vie w. This renders intellect as impersonal and unrelated from the person. Intellectual knowledge, therefore, is self-governing through contextual explanations rather than based on attributes to the person who posses it. Wisdom, however, adopts a contrary approach from intellect. It assumes a spiritual approach to defining different phenomena. The wise are anxious about life-defining issues as the significance of life. In the definition and contextualization of most subjects, wise individuals adopt a personal approach. The premises in the discourse to finding an answer to a situation and concern do not depend on rigid theories that have empirical proofs. Instead, the wise finds solutions based on their personal feelings and their experience, over time, that helps in explaining their opinions.

Feminism, its development since the 18th century and how it affected Research Paper

Feminism, its development since the 18th century and how it affected society of today - Research Paper Example The feminists assert that there are very few inherent differences that are unchangeable between men and women. There are however many individual differences between men and women. These individual and inherent differences are however not to imply that one gender is more capable than the other. The equality that is advocated for by the movement refers to equality in accordance to the laws of the land as well as social, political, an economic equality. While most people assume that feminism is a single or unified school of thought, it can be seen that the movement has evolved in three major waves. Each wave of has had distinct features or characteristics and can be seen to have been advocating for different rights. While some have criticized the movement, it has led to some major achievement for the women. It is important for one to understand the situation that the women were living in before the rise of the feminist movement. Such an understanding will help one to understand the chan ges that were brought about by the feminist movement. At the beginning of the 18thcentury, women did not receive any recognition under law. They were pronounced as being civilly dead when they got married. They were therefore not allowed to sign any contracts and they could not control the wages that they received. Their wages were controlled by the men in their lives. They were not given an opportunity to get an education and their position was expected to be at home taking care of their homesteads. A comparison of this situation with the current situation in the society reveals that a lot of changes have taken place. Most of the changes and the rights that the women have been able to achieve are as a result of the feminist activities (O’Neil 32). The influence of the feminist movement is seen to be reflected in the different areas of life in the society. The movement influences the social lives of the people and their economic life as well. The impact of feminism can also b e seen in the literary world. Many female writers chose to address the various feminist issues that faced them in their lives through their writing. As the different waves of feminism changed, so did the content for the writers who are considered as feminists. Because each wave addressed different social and economic issues, and this was reflected in their writing. The ‘first wave of feminism’ can be traced back to the late 18th century period. This wave targeted the injustices that were officially mandated and that were directed at women. The first wave of this movement was interconnected with other movements that sought reforms in the society. Such movements included the abolition movement and the temperance movement. The highlight of the wave was marked by the publication of Vindication of the Rights of Woman by Mary Wollstonecraft in 1972. The end of this wave can be seen to have been marked by the ratification of the Twentieth Amendment of the U.S. Constitution. Th is amendment gave the women voting rights and marked the beginning of the process of political empowerment for the women. The feminists during this period included Lucy Stone, Mary Wollstonecraft, and Helen Pitts among others. The movement also saw such achievements as educational opportunities for women. The first

Information Systems Design and sociotechnical systems Essay

Information Systems Design and sociotechnical systems - Essay Example The authors appreciate the need for proper systems to model and analyze the interaction and composition of software and hardware components with organizational and human actors. The authors evaluate and select the right trade-off between social and technical dimensions. They propose tool-supported procedures of requirement analysis for technical-social systems that adopt planning schemes for exploring the range of requirement alternatives in addition to a number of social criteria for their assessment. The authors illustrate the proposed approach using a case study. The publication proposes a systematic, tool-supported procedure that aims at supporting the designer in evaluating and exploring alternative configurations and frameworks of socio-technical system delegations. It supposes that the accomplishment of such processes be done through Artificial Intelligence planning techniques in constructing design alternatives. It also gives a set of assessment criteria for evaluating and comparing the available options (Volha, Paolo, & Mylopoulos, 2012, p. 7). The paper has presented the presented schemed process that supports the proposed approach. It also gives the outline of the planning, discussion and formalization of the concrete set of evaluation criteria. The white paper has reported on the assessment of the proposal through a number of case studies in addition to a series of scalable experiments. Bert, P. (2011, June 3). Sicio-Technocal Design of Knowledge Work & IT; A Case Study. Retrieved Feb 12, 2014, from Independent Consulting Social Scientist: http://moderntimesworkplace.com/good_reading/GRNewTech/STS.Design.of.KnowledgeWork_IT.v2.pdf The author uses a case study of E-File introduction into the system of an insurance company as an imperfect, but powerful example of the challenges and the potentials of designing technical and social elements of knowledge work interactively and concurrently. Bert explores a case study of a public insurance

Ethnography Assignment Worksheet Essay Example | Topics and Well Written Essays - 500 words

Ethnography Assignment Worksheet - Essay Example a between the black and white races in the Old Fourth Ward, and the Auburn Avenue’s main drag was called â€Å"the richest Negro street in the world† (McCall). There are also numerous films based on racism and class system that have been made in the past. One such film is A Day Without a Mexican in which a pink fog draws the Mexicans out of California. My fieldwork site is a park in the Downtown Manchester, NH. The neighborhood immediately surrounding my fieldwork site is like mixed commercial and residential. It is easy for me to get to my site since it is located in my home-city. The Veterans Park consists of a stage area for concerts and a memorial for fallen soldiers. I observed that the park is not divided and homeless and non-homeless people are mixed within the park. The US flags have been used to decorate the park. The park is next to a main street, which makes it sound like a typical city with the noises of people, cars, trucks, and traffic. Usually, the noise is more during the day than the night since the load of traffic in the night is lesser and also, the birds that chirp around during the day recede to their nests in the night. The land in the park is all covered in thick grass which is very pleasant and sweet to the smell. Occasionally, car fumes can be smelled as well, particularly when they are parked with a rush. The park setting is both relaxing and comfortable. Since it is a park, there are benches placed around the periphery of the green areas. The land is mostly covered in grass with concrete walkways running through the open areas. Many people bring food and eatables with them as the natural beauty makes the park a nice picnic spot. Most of the people are from the working class. Spceially, the civil servants and the private sector employees from surrounding buildings visit the park for recreation and timepass. Mnay visitors are middle-aged though the community of visitors is diverse as the visitors come with their families i ncluding children

Feminism, its development since the 18th century and how it affected Research Paper

Feminism, its development since the 18th century and how it affected society of today - Research Paper Example The feminists assert that there are very few inherent differences that are unchangeable between men and women. There are however many individual differences between men and women. These individual and inherent differences are however not to imply that one gender is more capable than the other. The equality that is advocated for by the movement refers to equality in accordance to the laws of the land as well as social, political, an economic equality. While most people assume that feminism is a single or unified school of thought, it can be seen that the movement has evolved in three major waves. Each wave of has had distinct features or characteristics and can be seen to have been advocating for different rights. While some have criticized the movement, it has led to some major achievement for the women. It is important for one to understand the situation that the women were living in before the rise of the feminist movement. Such an understanding will help one to understand the chan ges that were brought about by the feminist movement. At the beginning of the 18thcentury, women did not receive any recognition under law. They were pronounced as being civilly dead when they got married. They were therefore not allowed to sign any contracts and they could not control the wages that they received. Their wages were controlled by the men in their lives. They were not given an opportunity to get an education and their position was expected to be at home taking care of their homesteads. A comparison of this situation with the current situation in the society reveals that a lot of changes have taken place. Most of the changes and the rights that the women have been able to achieve are as a result of the feminist activities (O’Neil 32). The influence of the feminist movement is seen to be reflected in the different areas of life in the society. The movement influences the social lives of the people and their economic life as well. The impact of feminism can also b e seen in the literary world. Many female writers chose to address the various feminist issues that faced them in their lives through their writing. As the different waves of feminism changed, so did the content for the writers who are considered as feminists. Because each wave addressed different social and economic issues, and this was reflected in their writing. The ‘first wave of feminism’ can be traced back to the late 18th century period. This wave targeted the injustices that were officially mandated and that were directed at women. The first wave of this movement was interconnected with other movements that sought reforms in the society. Such movements included the abolition movement and the temperance movement. The highlight of the wave was marked by the publication of Vindication of the Rights of Woman by Mary Wollstonecraft in 1972. The end of this wave can be seen to have been marked by the ratification of the Twentieth Amendment of the U.S. Constitution. Th is amendment gave the women voting rights and marked the beginning of the process of political empowerment for the women. The feminists during this period included Lucy Stone, Mary Wollstonecraft, and Helen Pitts among others. The movement also saw such achievements as educational opportunities for women. The first

Ethnography Assignment Worksheet Essay Example | Topics and Well Written Essays - 500 words

Ethnography Assignment Worksheet - Essay Example a between the black and white races in the Old Fourth Ward, and the Auburn Avenue’s main drag was called â€Å"the richest Negro street in the world† (McCall). There are also numerous films based on racism and class system that have been made in the past. One such film is A Day Without a Mexican in which a pink fog draws the Mexicans out of California. My fieldwork site is a park in the Downtown Manchester, NH. The neighborhood immediately surrounding my fieldwork site is like mixed commercial and residential. It is easy for me to get to my site since it is located in my home-city. The Veterans Park consists of a stage area for concerts and a memorial for fallen soldiers. I observed that the park is not divided and homeless and non-homeless people are mixed within the park. The US flags have been used to decorate the park. The park is next to a main street, which makes it sound like a typical city with the noises of people, cars, trucks, and traffic. Usually, the noise is more during the day than the night since the load of traffic in the night is lesser and also, the birds that chirp around during the day recede to their nests in the night. The land in the park is all covered in thick grass which is very pleasant and sweet to the smell. Occasionally, car fumes can be smelled as well, particularly when they are parked with a rush. The park setting is both relaxing and comfortable. Since it is a park, there are benches placed around the periphery of the green areas. The land is mostly covered in grass with concrete walkways running through the open areas. Many people bring food and eatables with them as the natural beauty makes the park a nice picnic spot. Most of the people are from the working class. Spceially, the civil servants and the private sector employees from surrounding buildings visit the park for recreation and timepass. Mnay visitors are middle-aged though the community of visitors is diverse as the visitors come with their families i ncluding children

Method of the Ancient Essay Example for Free

Method of the Ancient Essay In the excerpt, Claude Perrault begins mundanely by recalling the Ancients’ belief in that the utilization of proportioning systems based on the human body would give aesthetic qualities and beauty to a building. Without a doubt, this topic of beauty, which resides from mathematical proportions, is readily discussed both visually and verbally through examples in all history and theory of architecture classes including Buildings, Texts and Contexts. However, what makes the text compelling to me is how Perrault brings into light the discrepancy in these proportioning systems that exists throughout history from the antiquity through to the renaissance. It is said that although the building orders may conform to certain proportions as a whole, the constituent parts of buildings, such as the precise dimensions of the members and its profiles, does not pertain to any strict rules or to a consensus of opinions amongst architects such that the building’s ultimate beauty does not lie only in proportions. Perrault’s juxtaposition of the beauty of buildings with the beauty of a human face clearly give weights to his argument: â€Å"a face can be both ugly and beautiful without any change in proportions; the contraction of the eyes and the enlargement of the mouth can be the same when one laughs as one weeps†. Perrault also points out that even though there is no single absolute proportioning rules for beauty, there are certain limitations to which one can deviate before a building loses its elegance. Through these flexibility and variability of indefinite rules, Perrault points out that by no means is the proportions preserved in architecture, of which is perceived by our eyes, are akin to the ones that govern musical harmonies, gained through our ears, as they are of immutable precision. These two sensory faculties, the eyes and the ears, work in processing data in different ways according to Perrault: the ear processes data without intervention of the intellect whilst the eyes work through the mediation of knowledge. Perrault then argues that since the proportions of edifice are usually oblivious to our eyes there must exists two different types of beauty: positive beauty and arbitrary beauty. Positive beauty as define by Perrault is for me quite the oppositive of Kant’s aesthetics judgement for that Perrault’s positive beauty are based on convincing reasons rather being disinterested and being ‘purposive without a purpose’. They are convincing reasons based on value and quality such as its rich materiality or even its precise execution. Arbitrary beauty, unlike positive beauty, is to me more like Kant’s aesthetics judgement in that it is universal, at least to a certain extent. Arbitrary beauty, as defined by Perrault, is the beauty where people have customarily come to agreement without any intrinsic qualities to justify such judgement.

Brand loyalty

Brand loyalty INTRODUCTION Brand loyalty is the preference of the consumer to buy a particular brand in a specific product category. Brand loyalist have the following mindset: I am committed to this brand, I am willing to pay a higher price for this brand over other brands and I will recommend this brand to other (Giddens, 2002). Greater loyalty leads to numerous benefits such as an improved market share, decline in marketing cost and improved opportunities for brand extension to name a few (Martin evans). The Business Cycle Dating Committee of the National Bureau of Economic research determined that in December 2007 the U.S. economy reached its peak in economic activities. The peak marked the end of the expansion period that began in November 2001 and the start of the recession episode. Recession is a considerable decline in all economic activity which affects employment, production and real income spread over the economy. The recession has forced many consumers to prioritise and cut back spending. But how will consumers cut back and by how much, will vary immensely by brand and by category. The money consumers spend on various brands in different product categories would vary person to person but one thing that remains constant is that each one evokes a set of positive feelings like powerful, confident, young, happy, stylish etc. Consequently, for a brand to do well in an economic downturn, it is vital for the brand to do more than just satisfy a need or service. It must create and maintain an emotional connection with its customers which would induce positive feelings in them and hence the consumer will keep coming back for more (Isakovich, 2008). In this regard, this research proposal would answer a few questions regarding the effects of recession on brand loyalty of consumers in the U.S. Firstly, how store brands have become more popular than name brands in supermarkets. Lastly, how luxury brands have benefitted even through recession. The structure of the proposal would include methodology, its literature review, research techniques, research time-table and a conclusion. RESEARCH METHODOLOGY Research methodology is a system of principles and methods of procedure followed by a researcher of any discipline. There are several paradigms of research methodology. The most quoted definition of paradigm is Thomas Kuhns (1962, 1970) concept in The Nature of Science Revolution, i.e. paradigm as the underlying assumptions and intellectual structure upon which research and development in a field of inquiry is based. The main components of a paradigm are ontology, epistemology and methodology. Under these comes the comparative study of different approaches like positivism, interpretivism and critical theory. Ontology is reality and the state of being. It is how things exist in the world. It is how we view objects in studies (Lecture 2). Reality can be subjective or objective. For example are people with free will wholly responsible for their actions or is life predetermined by situations. Subjectivists believe that something comes into existence only when one experiences it and gives it meaning. They believe that people have their own beliefs assumptions and perceptions so they experience realities in different ways. While objectivists consider that reality is independent of those who exist in it. From their point of view people react to situations in a predictable way since their behaviour is a part of the material world these can be determined by causes (Hatch, 2006). There are a few assumptions which have to be explained in order to carry out this research: Store brands also include private-label brands Luxury brands are the companies which sell true luxury commodities. In this study hypermarkets are also taken into account. Recession is still prevalent but the economy is improving so the study is of when it was at its worst. Brand loyalty will be restored to its original state once consumers have disposable income to spend. Epistemology is the theory of knowledge in which we study how we know the world (Lecture 2). It basically investigates and answers questions like how do people generate knowledge? How do we discriminate knowledge (for example: good from bad or valid from invalid)? How should reality be represented? Epistemology and ontology is interlinked since answers to these questions help to forge and depend on ontological assumptions (Hatch, 2006). Epistemology can be of two categories either positivist or interpretivist. Positive Epistemology is the search of accurate representation which is objective in nature (Lecture 2). It assumes one can learn about what actually happens in organizations by categorizing and scientifically measuring the behaviour of individuals and systems. They generate knowledge by gathering data and analysing it, then develop hypotheses and propositions and finally test these against the external reality to see if they are accurate (Hatch, 2006).Positivists use more of t he quantitative methods like questionnaires and surveys. Based on these methods they derive theoretical models for factual explanations. Interpretivist believe that there are multiple and subjective interpretations of the world. This means that there can be numerous understandings and interpretations of reality. Interpretive epistemology helps us to apply methods designed to understand meanings made by others and how they come to make these meanings (Hatch, 2006). The third approach is critical theory which is governed by conflicting, underlying structures -political, social, economic, ethnic, gender. Individuals can reconstruct their world by way of action and critical reflection (Voce, 2004). Methodology is figuring out how can the researcher go about finding out whatever she/he believes can be known (Guba, 1994). There are basically two ways or carrying out research Quantitative and Qualitative. According to ontology and epistemology the methodology is chosen. So if the ontology is objective then epistemology will be positivist and methodology will be quantitative. So in positivism quantitative methods are used like surveys, questionnaires and quantitative analysis. Positivists need more data and large samples to prove their study. But if the ontology is subjective then epistemology will be interpretivist and methodology will be qualitative. Interpretivists use qualitative methods like case studies, interviews and ethnographic style of investigation. Here researchers can lose context with large samples. Many researchers combine both quantitative and qualitative methods in one study this is known as the triangulation approach. This research proposal would be positivistic. The objects here would be independent from the external environment. Brand loyalty in customers is based on consumer behaviour which is predictable. In recession, since the disposable income of consumers have reduced it is very obvious that consumers will shift to cheaper brands in the short term. This brings brand loyalty down for the commodity or service. The research questions specifically are how store brands have become more popular than name brands and how luxury brands have benefitted through recession also. Addressing the first question it is based on consumer preferences which can be studied using quantitative methods. For example: does Mr.Simon prefer brand A over brand B in toothpastes? These results are quantifiable and are objective. Since we are addressing the issue of recession in the U.S., we have to keep in mind and study the product type as well since luxury brands did well in these times. Since luxury brands are bought by the wealthy, these brands did well. Not that the rich were not affected by recession but there are several reasons (discussed in the literature review) that the rich could not keep away from these brands. The behaviour of the affluent is predictable and one of the major causes luxury brands are flourishing. LITERATURE REVIEW A study released by Boston Consulting Group on 30th April, 2008 indicated that 73% of Americans said that they intended to cut down on spending in the next twelve months. In reality, spending has been on a steady drop each month since July 2008 (Bureau of Economics Analysis, 2008).The significance of brands for consumers in the U.S. has been continuously declining. Only 27% of Americans said they were ready to trade up for a superior brand (McGregor, 2008). Research denotes that the less personal the commodity, the lower the need to stay loyal to a particular brand (Isakovich, 2008). This research will cover two broad product categories which are household items and luxury goods. Due to the recession, one way consumers are cutting back on spending is by substituting more expensive name brands with less expensive store or private label alternatives (Isakovich, 2008). This is mostly seen in supermarkets since consumer have a wide variety of name and store products to choose from. Retailers are also sensing shopper experimentation. Supermarkets like Safeway Inc. and Kroger Co. recorded that sales of their store brands were on the rise. In this economy, customers are much more willing to try a private-label item, and were seeing signs that this is happening more and more as the year progresses, Kroger CEO David Dillon said on a conference call (Brown, 2008). Thomas Falk (CEO) of Kimberly -Clark Corp noted that the companys once famous potty training which used to be one of the biggest sales growth products in the baby aisle has reduced in it sales and consumers now prefer diapers since the diaper is less expensive (Brown, 2008). Mintel International, a market research company by interviewing 3000 customers found out that 40% of primary household shoppers said they would buy store brand paper because it is cheaper than national brands. This is one product category where consumer strictly trade for budgetary reasons. Paper napkin, facial tissue and paper towels suffered the sharpest declines in the past year though toilet paper did well (Brown, 2008). Laundry habits were another sector in which change in consumption patterns was seen. Consumers shifted to cheaper detergents and softeners this is a rare shift since it is one of the most brand loyal among product categories (Brown, 2008).According to Nielson Co. private label soaps and other bath products did very well and were up by 23% and skin care products was up by 16%. It is obvious that lower incomes consumers were hit the most and reacted to changes quickly by changing to store brands. Upper income consumers have also started reacting to prices. According to a survey conducted by IRI consumers with household incomes of $100,000 are making considerable changes. A report Shopper in crisis found that upper -income consumers had reduced spending on nonessential groceries by 41%. In another IRI survey of 1000 respondents of all income levels, 52% of consumers said they try to make personal -care items last longer and a quarter of them share these products with household members (Brown, 2008). Nielson reported from late November 2008 that private label brands grew in the U.S. to $81 billion that would a 10% growth from 2007 (Wong, 2008). This study also reported that 72% of respondents viewed private label brands while 62% viewed store brands as good alternatives to name brands (Wong, 2008). There is empirical evidence that consumers have shifted to private label or store brands and have become more loyal to name brands. In numerous of product categories people often buy the same products or brands repeatedly either as several purchases or on the same purchase, For example groceries, we buy them week after week but that does not show our loyalty towards the brands. Consumers are brand loyal when even if a cheaper option is available the consumer would still be committed to a brand due to trust (Martin evans). Riechheld (1988) argued that repeat purchasing pattern of a consumer cannot be called loyalty. Since here consumers are forgoing trust and accepting a lower quality product and are willing to change to a less expensive alternate. This aspect of research should be analysed as well. This one of the drawback of this research whether repeat purchasing behaviour can be called brand loyalty or not. The marketing and branding are very different for luxury commodities compare to household commodities. As for luxury goods their business plan places trust designer and his artistic vision and anticipates that it will lure customers. There are several reasons why consumers purchase luxurious brands. Some of which is uniqueness of the brand /product, materialistic attitude of the consumer, quality associated with the brand, functional advantages and financial associations with luxury product (Shukla, 2009). The rich tend to fly towards quality this is reason that luxury brands will survive the recession specially the ones with heritage and a strong identity (Fellowes, 2008). The rich continue to spend on private jets, boats, cars, art, jewellery and beautiful garments. This is because they are used to it but now during recession they will buy carefully and ensure value for their money. Prince and associates, a consulting company conducted a recent survey which saw that consumers worth more than $10million including assets intended to increase their expenditure this year on luxury goods but those with less than that will cut back (Sullivan, 2007). In these times of recession it is important that we differentiate between affordable luxury and true luxury. The affordable luxury sector especially cars, travel, perfumes and clothing which have been hit by recession. Since the broader market is subdued, as middle-income consumers have deserted luxury brands which they used to buy during the good times. This is why profits of the affordable luxury companies have significantly dropped (Clark, 2009). The Companies which come under true luxuries have actually flourished even during recession. Since only a few individuals have cash to spare they look for genuine luxury and not something everyone can own (Clark, 2009). These brands have to have an image of exclusivity and qual ity but at the same time they should achieve enough scale to be profitable. Brand like these have very glamorous stores and boutiques, their goods are never crammed into sales racks or sold at discount stores. Louis Vuitton, Hermes and Rolls-Royce are a few of the companies which did well even in the face of recession. According to the Top 100 Most Powerful Brands, Louis Vuitton tops the luxury category with a enormous brand value of $19.4 billion and following behind is Hermes at $7.86 billion (Sherman, 2009). Despite the Automotive industry not doing well in recession but the luxurious car manufacturer Rolls-Royce accounted a 20% increase in sales for the year 2008. According to the company it sold 1010 cars in 2007 compared to 1212 cars in 2008 (Clark, 2009). Providing Empirical evidence and conceptual understanding it now clear that all luxury commodities did not flourish during the economic downturn. It was only the very exclusive and unique brands that were successful. Other mid-market retailers of luxury brands did not abide by this and reduced their prices. For example Saks Fifth Avenue went on a price cut rampage last fall, offering 70% discount on several high-end brands. But stores like Louis Vuitton remained at full price. Strategies should be implemented but in such a way that the exclusivity of the brand should not be lost whether in good or bad times. RESEARCH METHODS Research methodology and research methods are interlinked because methodology determines which methods to use quantitative or qualitative. In reference with this research proposal, ontology is objective which makes epistemology; positivism therefore the methodology used here would be Quantitative. Research questions under consideration are firstly, how store brands have become more popular than name brands in supermarkets and lastly, how luxury brands have benefitted even through recession. Both have a positivistic approach, so to investigate this topic, more of quantitative methods will be used. Usually both quantitative and qualitative methods are combined in order to get the fuller picture. Methodology can be only one but methods can vary. In this study of how brand loyalty was affected in the U.S. due to recession, several research methods can be used. Some of which are interviews, questionnaires, surveys, focus groups, case studies, observation, laboratory experiments and mathematical modelling. Interviews can be structured, semi-structured or unstructured. In structured the question are preset, in semi-structured the some questions are preset the rest are spontaneous and in unstructured there are no preset questions only a framework of the research questions. Structured Interviews are more quantitative in nature. Questionnaires and survey are also quantitative method of research. These have open or close ended questions which individuals answer. There are various mediums to do a survey via mail or telephone or face to face. Written questionnaires and surveys have a coding system to analyse their results. Laboratory experiments and mathematical modelling are also quantitative methods. Case-studies and observations ar e qualitative methods. Being a positivist study, the research methods which will be employed will be structured interviews and Questionnaires. Structured interviews will be used to answer the first research question on store brands and Questionnaires will be utilized for the second research question on luxury brands. To test whether store or private label brands did better than name brands in supermarkets structured interviews would be planned with supermarket giants in the U.S. A representative of the market research team would be interviewed in order to gain insights and facts into this topic. Using questionnaires for this topic would be difficult because there is a very huge market to cover since lower, middle and upper income consumers reacted during recession. These interviews will be structured and through the telephone (convenient and less time consuming). There will be five supermarkets involved Aldi, Costco, Kroger, Safeway and Wal-mart supercenters. Interviewers will be informed that where their information will be used and all the necessary background information will be given beforehand. The length of the interview will be merely 20 minutes. There will be four questions asked. For example: has the market share of their store brand increased? According to them the cause of this increa sed popularity? Which products were doing very well as store brands? What does the future hold for name brands endorsed in their respective supermarkets? There will be one open ended question at the end of the interview. If possible within the level of confidentiality secondary data supporting the information just given will be requested for. This would help since there will be a back up of empirical evidence. Questionnaires will be utilized to prove that the brand loyalty of luxury brands in U.S. consumers was intact during recession. These questionnaires will be sent out to consumers and their families worth more than ten million dollars including assets. Since the range is so restrictive in money matters there will be no age barrier. This Questionnaire will let us know that whether the ultra wealthy are ready to spend on true luxury brands or not. These Questionnaires will be emailed to suitable candidates. Assuming the response rate of questionnaires is only 20%, 5000 questionnaires will have to be sent out in order to get 1000 respondents. There will be very little cost associated with these questionnaires. The Questionnaire will provide clear instructions for respondents and will state the purpose and aims of the study. Respondents will not have to disclose their names but they will have to disclose their age and income. There will be an income and age bracket which they will have to place themselves in at the end of the questionnaire. There would be a code to analyse results since there will be there will be all multiple choice questions. There will be one question in the end which will not be a multiple choice and the respondents will have to express their views. Examples of questions would be: Do you feel brand loyal towards any luxurious brand? Do you still purchase these brands? What is the average price range you would spend annually on these brands? How often do you purchase products from these brands? Why are you loyal to these brands? Other than the last question all other questions are multiple choice questions. There are several problems which one can face with these research methods. Structured interviews may be expensive and time consuming. It is open to manipulation in answers by the interviewer. It might be also difficult to summarise findings. Interviewing giants can be a problem because they might not want to disclose information regarding their brand because of several reasons. A questionnaire has its own set of problems. They have a very low response rate and responses can be biased. Many of the respondents may not understand the questions. Its not certain that the intended individual filled in the questionnaire. Lastly, we cannot check responses with the respondent (Nef, 2008). Data Protection and ethics have also become an integral part of a research topic. In this research data will be held fairly, lawfully, accurately and relevantly. It will not be used for any future purposes and will not be held any longer than necessary. Ethics will also be taken care of while dealing with individuals. Confidentiality and anonymity of respondents will be respected. The research design will be reviewed to further ensure integrity and quality. There is no forms of compulsion to take part in the research it is purely voluntary. There is no sexism or racism involved in this study. CONCLUSION Impulsive buying used to be one of the most distinct features of American Consumers. According to Abrahams (1997) 62% of supermarket and 80% of luxury -goods sales in the U.S. were impulsive (Zhang, 2009). But these are the two product categories in which due to recession either people are moving to name brands in supermarkets or are buying luxury goods very carefully to ensure value for money. The basic aim of this research is to show how the popularity of store brands have increased and how the luxury brand still make profits during recession. The recession has created great opportunities for store brands to advance their market position. As for the luxury brands, true luxury will always sell at its highest price so it remains exclusive and unique. Both product categories one of household items and the other of luxury commodities are very different but it shows a contrast in the market which is affected by the recession. Bibliography Brown, E. (2008). At the Supermarket Checkout, Frugality Trumps Brand Loyalty . Wall Street Journal , D1. Bureau of Economics Analysis. (2008, November 25th). National Incone and product accounts. Retrieved from Hhttp://www.bea.gov/nationalH Clark, N. (2009, February 24th). Luxury brands ditch mass-market strategy as credit crunch deepens. Marketing magzine. Fellowes, J. (2008, October 17th). Financial crisis: Luxury brands boom as rich fly to quality. Telegraph. Giddens, N. (2002, August). Brand Loyalty. Guba, L. a. (1994). Handbook of Qualitative Research. In Competing paradigms in qualitative research (p. Chapter 6). U.S.A: Sage Publishers. Hatch, M. a. (2006). Organisation Theory:Modern,Symbolic and Postmodern Perspectives. What is Organisational Theory Handout . Oxford: Oxford University Press. Isakovich, H. (2008). How brands can capitalize on an economic downturn. Consumer spending in a recession. New York: Interbrand. Martin evans, A. J. (3rd edition). Consumer Behaviour. John Willey and Sons. McGregor, J. (2008, April 30th). Consumer Spending in a Recession. Retrieved from Businessweek: http://www.businessweek.com/careers/managementiq/archives/2009/04/consumer_spendi.html Mclean, C. (n.d.). Research Methodology. Lecture 2. Nef. (2008). Comparison chart. Retrieved from http://www.proveandimprove.org/new/meaim/documents/CompareChart.pdf. Sherman, L. (2009, May 10th). Powerful luxury brands that say, what recession?. Forbes. Shukla, D. P. (2009, May 1st). Luxury brands in recession: Developing a better value proposition and luxury brand strategy . Retrieved from Perspectives: http://pauravshukla.blogspot.com/2009/05/luxury-brands-in-recession-developing.html Sullivan, A. (2007, March 7th). Luxury brands covet the recession-proof. 1. New York Times. Voce, A. (2004, November). Introduction to research paradigms. Handout for Qualitative Research Module. Wong, E. (2008, November 17th). Nielson: Private Label Deemed Equal to Name Brands. BrandWeek . Zhang, Y. (2009). Power-Distance Belief and Impulsive Buying. Journal of Marketing Research, 4.

Class Politics in the United States :: Politics Political Essays

A distinctive feature of US politics, in comparison with most other industrialized nations in the world, is its virtual lack of class-based politics. President George W. Bush, for instance, has said that class is for ‘European democracies or something else—it isn’t for the United States of America. We are not going to be divided by class’ (cited in Harrigan, 2000: 6). And this seems to be the general attitude that pervades all of American society, to the extent where militating on the basis of class could even be seen as culturally abhorrent. It is a fact that in the 1990s, trade union membership accounted for only 15 percent of all wage and salary workers, down from 25 percent in 1975. This is despite 30 percent of all workers still employed in blue-collar jobs as of 1996 (McKay, 2001: 226; Vanneman and Cannon, 1987: 5). Between the two major political parties, the Democrats and the Republicans, there are only relatively minor ideological differences, with the former leaning slightly more to the ‘liberal’ side, while the later are more ‘conservative’, though neither articulates anything near resembling class politics. This has led to much speculation among scholars as to why this could be the case. A number of reasons have been posed, including: 1. America is mainly a middle class society, with an individualistic culture; high levels of social mobility; and equality of opportunity, which are prized over collective action. 2. America does not have a feudal past, from which class cleavages can be drawn. 3. America is the richest industrialized nation in the world, and therefore has an overall higher standard of living, which minimizes any potential for class action. 4. The American working class is divided sharply along ethnic and racial lines. 5. The American two-party system makes it difficult for radical political parties to develop. However, despite this lack of class politics, the US continues to experience some of the most exacerbated income and wealth inequalities in the industrialized world, with the gap between the rich and the poor growing over the past thirty years. In addition, the proportion of the population living in poverty, according to official figures, is at around 14-16 percent (McKay, op. cit. :27). This raises the question as to the nature of class in the United States, and as to how the US class structure (if one exists) is reflected in mainstream politics.

Contrasting Views of bell hooks and Toni Morrison :: comparison compare contrast essays

Contrasting Views of bell hooks and Toni Morrison Even though people might have similar backgrounds it doesn't mean that they share the same opinions. This is evident in the works of bell hooks and Toni Morrison. bell hooks article mainly deals with the concept of racism and feminism. Her article looks at the movie about her people in a negative light. The other articles by Toni Morrison look at life and what it holds in a positive light. From the different works, I sense that bell hooks looks at the world with pessimism and Toni Morrison views the world with optimism. Toni Morrison feels that everybody is equal and the same. While bell hooks feels that everybody is not equal. From her opinions of female black woman you sense that she feels that life is not fare. On the other hand Toni Morrison's work makes her seem like a person who thinks that you make the best with what you are given. Authors make many choices when they write. These choices give authors the uniqueness that they share from their counterparts. Many authors use different writing techniques to portray their point. Others take different views or opinions to portray their ideas on paper. However authors do use similar styles and opinions to portray their ideas in writing. In the works of Toni Morrison and bell hooks many similarities and differences can be drawn from their writings. Both authors come from similar backgrounds, Black middle aged females. Their background provides them with many bizarre and extraordinary beliefs that are uncommon to most Americans. The article "Sorrowful Black Death is not a hot ticket" was written by bell hooks to discuss the image of Black families portrayed by Hollywood. In particular she discusses the image of the Black family in Spike Lee's movie Crooklyn. The first point that bell hooks makes about Spike Lee's portrayal of Black families is his depiction of the black female child. In his movie Troy, a ten-year-old girl is put in the role of "mini-matriarch because her mother is sick and dying requires of Troy that she relinquish all concern with pleasure and play, that she repress desire"(p.

Physics Study Notes Hsc

Physics Summary Contents Core Topic One: Space 1. 2. 3. 4. Gravity Space Launch and Return Future Space Travel Special Relativity 2 3 13 14 Page Core Topic Two: Motors and Generators 1. 2. 3. 4. 5. The Motor Effect Electromagnetic Induction Electric Generators Transformers Electric Motors 19 24 27 29 31 Core Topic Three: From Ideas to Implementation 1. 2. 3. 4. Cathode Rays Quantum Theory Solid State Devices Superconductivity 32 37 43 48 Option Topic: Quanta to Quarks 1. . 3. 4. 5. 6. Models of the Atom Quantum Physics The Electron Microscope Applications of Radioactivity Nuclear Applications The Structure of Matter 53 57 59 61 66 67 William Kim HSC Physics Summary | page 1 Core Topic One: Space 1. The Earth has a gravitational field that exerts a force on objects both on it and around it  § Define weight as the force on an object due to a gravitational field The weight of an object is the force of gravity acting on it. r W = mg Where W is the weight in newtons (N), m is the mass i n kilograms (kg) and g can be either: 1. The acceleration due to gravity (= 9. 8 m/s/s at the Earth’s surface); or 2. The gravitational field strength (= 9. 8 N/kg at the Earth’s surface).  § Define gravitational potential energy as the work done to move an object from a very large distance away to a point in a gravitational field. As we lift an object from the ground to a height above the ground we do work on it. This work is stored in the object as gravitational potential energy.For an object of mass m at a height h above the Earth’s surface the gravitational potential energy E is given by: E p = mgh However this equation is valid only when the object is near the Earth’s surface. The gravitational potential energy is a measure of the work done in moving an object from infinity to a point in the field. The general expression for the gravitational potential energy of an object of mass m at a distance r from the centre of the Earth (or other planet) is g iven by: E p = ? G mM E r Newton’s Law of Universal Gravitation m F = G 12 2 r where G is the universal gravitational constant. The Gravitational Field Surrounding any object with mass is a gravitational field. g= Gm r2 Where M is the mass of the Earth (or other planet). Change in Gravitational Potential Energy The change in potential energy of a mass m1 as it moves from infinity to a distance r from a source of a gravitational field (due to a mass m2) is given by: mm ? E p = G 1 2 r Change in Gravitational Potential Energy Near the Earth (when radius increases from A to B) ?1 1? ?E p = GmM E ? ? ? ?r ? ? A rB ? William Kim HSC Physics Summary | page 2 . Many factors have to be taken into account to achieve a successful rocket launch, maintain a stable orbit and return to Earth  § Describe the trajectory of an object undergoing projectile motion within the Earth’s gravitational field in terms of horizontal and vertical components Any moving object that moves only und er the force of gravity is a projectile. The horizontal motion of a projectile is independent to the vertical motion. The reason for this result is that gravity is the only force acting on the objects and this always acts towards the centre of the Earth.Projectile motion can be analysed by realising that: 1. The horizontal motion is constant velocity. 2. The vertical motion of constant acceleration (with acceleration of g). Equations of Uniformly Accelerated Motion r r r v = u + at r r 1r s = ut + at 2 2 2 2 v = u + 2 as The Path of a Projectile The velocity at any point of the path of a projectile is simply the vector sum of the horizontal and vertical velocity components at that point. ?y = k (? x ) 2 ? ag ? k =? 2 ? ? 2u ? ? x? The horizontal component is constant.The vertical component changes at g, the acceleration due to gravity. Trajectories The path followed by a projectile – its trajectory – is a parabola (or linear) (1) Horizontal motion: ? x = u x t 1 (2) Ve rtical motion: ? y = a g t 2 2 From (1): ? x t= ux Combining (2) & (3): 1 ? ?x ? 1 ag ? y = a g ? ? = (? x )2 2 ? u ? 2 ? x? 2 ux 2 ux ? y ? x William Kim HSC Physics Summary | page 3  § Describe Galileo’s analysis of projectile motion Galileo was responsible for deducing the parabolic shape of the trajectory of a projectile.Galileo’s analysis of projectile motion led him to consider reference frames. These are what all measurements are compared to. The concept of Galilean relativity refers that the laws of mechanics are the same in a frame of reference that is at rest or one that moves with constant velocity.  § Explain the concept of escape velocity in terms of the: o gravitational constant o mass and radius of the planet If an object is projected upward with a large enough velocity it can escape the gravitational pull of the Earth (or other planet) and go into space.The necessary velocity to leave the Earth (or other planet) is called the escape velocity. Escape velocity depends on the gravitational constant, the mass and radius of the planet. Suppose an object of mass m is projected vertically upward from the Earth’s surface (mass of M and radius R) with an initial velocity u. The initial mechanical energy, that is, kinetic and potential energy is given by: E k i + E pi = 1 M m mu 2 ? G E 2 RE Let us assume that the initial speed is just enough so that the object reaches infinity with zero velocity.The value of the initial velocity for which this occurs is the escape velocity ve . When the object is at infinity the mechanical energy is zero (the kinetic energy is zero since the velocity is zero and the potential energy is zero because this is where we selected the zero of potential energy). Hence 1 M m mve2 ? G E = 0 which leads to: 2 RE ve = 2GM E RE William Kim HSC Physics Summary | page 4  § Discuss Newton’s analysis of escape velocity Circular Motion The motion of an object in a circular path with constant speed is cal led uniform circular motion.Although the speed remains the same in uniform circular motion, it follows that an object travelling in a circular path must be accelerating, since the velocity (that is, the speed in a given direction) is continually changing. r r v1 ? v2 v1 = v 2 r v2 r The change in velocity is given by: v2 r r r r v1 ? v = v 2 ? v1 r ? v1 r r ? v r and since: a = ? v r ? t ? v it follows that the object is accelerating. Isaac Newton proposed the idea of artificial satellites of the Earth. He considered how a projectile could be launched horizontally from the top of a high mountain so that it would not fall to Earth.As the launch velocity was increased, the distance that the object would travel before hitting the Earth would increase until such a time that the velocity would be sufficient to put the object into orbit around the Earth. (A higher velocity would lead to the object escaping from the Earth. ) Centripetal Acceleration As can be seen, when the change in veloc ity is placed in the average position between v1 and v2, it is directed towards the centre of the circle. When an object is moving with uniform circular motion, the acceleration (the centripetal acceleration) is directed towards the centre of the circle.For an object moving in a circle of radius r with an orbital velocity of v, the centripetal acceleration a is given by: v2 ac = r Earth Orbits A satellite can be put into Earth orbit by lifting it to a sufficient height and then giving it the required horizontal velocity so that it does not fall back to Earth. For the satellite to circle the Earth, the centripetal force required is provided by the gravitational attraction between the satellite and the Earth. Hence the centripetal acceleration is given by: v2 g= R William Kim HSC Physics Summary | page 5  §Use the term ‘g forces’ to explain the forces acting on an astronaut during launch g-forces on Astronauts Humans can withstand 4g without undue concern. Accelerations up to ~10g are tolerable for short times when the acceleration is directed parallel to a line drawn between the person’s front and back. The human body is relatively unaffected by high speeds. Changes in speed, however, that is, accelerations, can and do affect the human body creating ‘acceleration stress’. g-forces Acceleration forces – g-forces – are measured in units of gravitational acceleration g.For example, a force of 5g is equivalent to acceleration five times the acceleration due to gravity. If the accelerations are along the body’s long axis then two distinct effects are possible: 1. If the acceleration is in the direction of the person’s head they may experience a ‘black out’ as the blood rushes to their feet; or 2. If the acceleration is towards their feet, they may experience a ‘red out’ where the blood rushes to their head and retina.  § Compare the forces acting on an astronaut during launch with what happens during a roller coaster rideAs you ‘fall’ from a height, you experience negative g-forces (you feel lighter). When you ‘pull out’ of a dip after a hill or follow an ‘inside loop’, you experience positive g-forces (you feel heavier). The positive g-forces are like those astronauts experience at lift-off. Consider a rider in a car at the bottom of an inside loop. The rider has two forces acting on them: 1. Their normal weight (mg) acting down; and 2. The ‘normal reaction force’ (N) acting up. This is the push of the seat upwards on their bottom.Assume that the loop is part of a circle of radius R. A centripetal force is required for the rider to travel in a circle. This is the difference between the normal force and the weight force, that is: mv 2 mv 2 N ? mg = : N = mg + R R The g-forces are found from the ‘normal force’ divided by the weight. That is: N = mg mg + mv 2 2 R = 1+ v mg gR N mg g’s felt by rider = William Kim HSC Physics Summary | page 6  § Discuss the impact of the Earth’s orbital motion and its rotational motion on the launch of a rocketA moving platform offers a boost to the velocity of a projectile launched from it, if launched in the direction of motion of the platform. This principle is used in the launch of a rocket by considering that the Earth revolves around the Sun at 107,000km/h relative to the Sun and rotates once on its axis per day so that a point on the Equator has a rotational velocity of approximately 1,700km/h relative to the Sun. Hence, the Earth is itself a moving platform with two different motions which can be exploited in a rocket launch to gain a boost in velocity.Earth Orbit A rocket heading into orbit is launched to the east to receive a velocity boost from the Earth’s rotational motion. An Interplanetary Trip The flight of a rocket heading into space is timed so that it can head out in the direction of the Earth†™s motion and thereby receive an extra boost.  § Analyse the changing acceleration of a rocket during launch in terms of the: Law of Conservation of Momentum Forces experienced by astronauts Law of Conservation of Momentum Rocket engines generate thrust by burning fuel and expelling the resulting gases.Conservation of momentum means that as the gases move one way, the rocket moves the other. (Momentum before the burning is zero; hence the momentum after is also zero. The gases carry momentum in one direction down, and so the rocket carries an equal momentum in the opposite direction up. ) As fuel is consumed and the gases expelled, the mass of the system decreases. Since acceleration is proportional to the thrust and inversely proportional to the mass, as the mass decreases, the acceleration increases. Hence the forces on the astronauts increase.Forces Experienced by Astronauts g forces varied during the launch of Saturn V, a large three-stage rocket used to launch the Apollo sp acecraft. This is attributed to the sequential shutdown of the multiple rocket engines of each stage – a technique designed specifically to avoid extreme g forces. William Kim HSC Physics Summary | page 7  § Analyse the forces involved in uniform circular motion for a range of objects, including satellites orbiting the Earth Motion Whirling rock on a string Electron orbiting atomic nucleus Car cornering Moon revolving around Earth Satellite revolving around EarthFc Provided By†¦ The string Electron-nucleus electrical attraction Friction between tyres and road Moon-Earth gravitational attraction Satellite-Earth gravitational attraction  § Compare qualitatively and quantitatively low Earth and geostationary orbits Low Earth Orbit A low Earth orbit is generally an orbit higher than approximately 250 km, in order to avoid atmospheric drag, and lower than approximately 1000 km, which is the altitude at which the Van Allen radiation belts start to appear.The space shuttle utilises a low Earth orbit somewhere between 250 km and 400 km depending upon the mission. At 250 km, an orbiting spacecraft has a velocity of 27,900km/h and takes just 90 minutes to complete an orbit of the Earth. Geostationary Orbit A geostationary orbit is at an altitude at which the period of the orbit precisely matches that of the Earth. If over the Equator, such an orbit would allow a satellite to remain ‘parked’ over a fixed point on the surface of the Earth throughout the day and night.From the Earth such a satellite appears to be stationary in the sky, always located in the same direction regardless of the time of day. This is particularly useful for communications satellites because a receiving dish need only point to a fixed spot In the sky in order to remain in contact with the satellite. The altitude of such an orbit is approximately 38,800 km. If a satellite at this height is not positioned over the Equator but at some other latitude, it will not remain fi xed at one point in the sky.Instead, from the Earth the satellite will appear to trace out a ‘figure of eight’ path each 24 hours. It still has a period equal to the Earth’s, however, and so this orbit is referred to as geosynchronous. William Kim HSC Physics Summary | page 8  § Discuss the important of Newton’s Law of Universal Gravitation in understanding and calculating the motion of satellites Using Newton’s Law of Universal Gravitation combined with the expression for centripetal force, we can see that the orbital velocity required for a particular orbit depends nly on the mass of the Earth, the radius of the Earth and the altitude of the orbit (distance from the surface of the Earth). Given that the mass and radius of the Earth have fixed values, this means that altitude is the only variable that determines the specific velocity required. In addition, the greater the radius of the orbit, the lower the orbital velocity required. Once a launch ed rocket has achieved a sufficient altitude above the surface of the Earth, it can be accelerated into an orbit. It must attain a specific speed that is dependent only upon the mass and radius of the Earth and the altitude above it.If that speed is not reached, the spacecraft will spiral back in until it re-enters the atmosphere; if the speed is exceeded, it will spiral out. This can be considered by appreciating that the simplest orbital motion is a uniform speed along a circular path around the Earth. Uniform circular motion, as already mentioned, is a circular motion with a uniform orbital velocity. According to Newton’s First Law of Motion, a spacecraft in orbit around the Earth, or any object in circular motion, requires some force to keep it there, otherwise it would fly off at a tangent to the circle.This force is directed back towards the centre of the circle. In the case of spacecraft, it is the gravitational attraction between the Earth and the spacecraft that acts to maintain the circular motion that is the orbit. The force required to maintain circular motion, known as centripetal force, can be determined using the following equation: mv 2 FC = r The application of Newton’s Law of Universal Gravitation to the orbital motion of a satellite will produce an expression for the critical orbital velocity mentioned earlier.Recall that this law states that the gravitational attraction between a satellite and the Earth would be given by the following expression: m m FG = G E 2 S r This gravitational force of attraction also serves as the centripetal force for the circular orbital motion, hence: FG = FC Therefore, we can equate the formula for FG with that for FC: m E mS m S v 2 G = r r2 ? v = GmE r where v = orbital velocity (ms-1) where r = rE + altitude (m) William Kim HSC Physics Summary | page 9 Kepler’s Third Law: The Law of Periods Further, we can use the expression for orbital velocity to prove Kepler’s Third Law – the Law of Periods.The period or the time taken to complete one full orbit can be found by dividing the length of the orbit (the circumference of the circle) by the orbital velocity, v. 2? r T= v Changing the subject of this expression to v and then substituting into the formula for v given above: 2? r Gm E = T r 3 Gm E r ? 2 = T 4? 2 This means that for any satellite of the Earth at any altitude, the ratio r3:T2 always equals the same fixed value. William Kim HSC Physics Summary | page 10  § Describe how a slingshot effect is provided by planets for space probesMany of today’s space probes to distant planets such as Jupiter use a gravitational ‘slingshot’ effect (also known as a gravity-assist trajectory) that brings the probe close to other planets to increase the probe’s velocity. In 1974, Mariner 10 was directed past Venus on its way to Mercury. The Pioneer and Voyager probes also used this method. Consider a trip to Jupiter such as the Galileo prob e that involved a single fly-by of Venus and two of the Earth. As the probe approaches Venus, it is accelerated by Venus’ gravitational attraction, causing it to speed up relative to Venus. By Newton’s Third Law, Venus will also experience a force slowing it down. It’s mass, however, is so much greater than that of the probe that the velocity decrease is imperceptible. ) As the probe passes Venus, its speed is reduced (relative to Venus). Relative to the Sun, however, its speed has increased. The probe picks up angular momentum from the planet (which loses an equal amount of an angular momentum). Gravity allows the ‘coupling’ between the probe and planet to facilitate the transfer. For this reason, gravity-assist trajectories should more correctly be called angular momentum-assist trajectories. f = vi + 2Vi Planet vi Spacecraft Vi Vf  § Account for the orbital decay of satellites in low Earth orbit All satellites in low Earth orbit are subject to some degree of atmospheric drag that will eventually decay their orbit and limit their lifetimes. As a satellite slows, it loses altitude and begins a slow spiral downwards. As it descends, it encounters higher density air and higher drag, speeding up the process. By the time the satellite is below an altitude of 200 km it has only a few hours left before colliding with the Earth. The re-entry process generates much heat and most satellites burn up (vaporise) before impacting.William Kim HSC Physics Summary | page 11  § Discuss issues associated with safe re-entry into the Earth’s atmosphere and landing on the Earth’s surface There are significant technical difficulties involved in safe re-entry, the most important being: 1. The heat generated as the spacecraft contacts the Earth’s atmosphere; and 2. Keeping the retarding-forces (g-forces) within safe limits for humans. Heating Effects The Earth’s atmosphere provides aerodynamic drag on the spacecraft a nd as a result high temperatures are generated by friction with air molecules. Identify that there is an optimum angle for re-entry into the Earth’s atmosphere and the consequences of failing to achieve this angle. g-Forces The angle of re-entry is critical: too shallow and the spacecraft will bounce off the atmosphere back into space; too steep and the g-forces will be too great for the crew to survive (and the temperatures generated with the atmosphere will be too high even for the refracting materials used). The ‘allowed’ angle of re-entry is –6. 2 °  ± 1 ° relative to the Earth’s horizon. William Kim HSC Physics Summary | page 12 3.Future space travel and exploration will entail a combination of new technologies based on current and emerging knowledge  § Discuss the limitation of current maximum velocities being too slow for extended space travel to be viable Scientists have not yet been able to produce speeds of spacecraft more than a f ew tens of thousands of kilometres per hour. When travelling to distant planetary objects, the engines of spacecraft are not on as spacecraft rely on inertia to move along. To increase the speed significantly would require the engines to be operating, which would require more fuel.More fuel would require more thrust putting the spacecraft into orbit, which would require more fuel and so on. To increase the speed of spacecraft to values that would make interplanetary travel feasible requires a whole new technology (one not based on the emission of gases produced by combustion). Clearly, while current maximum velocities are just adequate for interplanetary travel, they are entirely inadequate for interstellar travel.  § Describe difficulties associated with effective and reliable communications between satellites and earth caused by: – distance – van Allen radiation belts – sunspot activityDistance Microwaves and radio waves, like all EM waves, travel through sp ace at the speed of light. This is the fastest speed possible in our universe and therefore places a limit on the speed and response time of space communications. The immense distance involved in space communications creates a distance-related time lag. Also, as EM radiation obeys an inverse square law, there is a loss of signal strength as distance increases. This is referred to as space loss. Van Allen radiation belts There are two belts of energetic charged particles, mainly electrons and protons, lying at right angles to the equator of the Earth.Some of the solar wind particles become trapped in the Van Allen radiation belts. Intense solar activity can disrupt the Van Allen Belts. This in turn is associated with auroras and magnetic storms. The charged particles drifting around the Earth in the outer belt corresponds to an electric current and hence has an associated magnetic field. Once or twice a month this current increases and as a result its magnetic field increases. This c an lead to interference of short wave radio communication, errors in communication satellites and even failure of electrical transmission lines.Sunspot activity Sunspots are associated with the solar wind (consisting of a stream of charged particles). The solar wind affects the Earth’s magnetic field and this in turn affects radio communication. William Kim HSC Physics Summary | page 13 4. Current and emerging understanding about time and space has been dependent upon earlier models of the transmission of light  § Outline the features of the ether model for the transmission of light It was believed that light waves require a medium to propagate. Although nobody could find such a medium, belief in its existence was so strong that it was given a name – the ether.The ether: – Filled all of space, had low density and was perfectly transparent – Permeated all matter and yet was completely permeable to material objects – Had great elasticity to support and propagate the light waves  § Describe and evaluate the Michelson-Morley attempt to measure the relative velocity of the Earth through the ether The Ether Wind Because the Earth was moving around the Sun, it was reasoned that an ether wind should be blowing past the Earth. However, if a wind blows, the speed of sound relative to the stationary observer would vary.Thus it was believed that the speed of light should vary due to the presence of the â€Å"ether wind†. It was in an attempt to detect this difference that Michelson and Morley did their famous experiment. The Michelson-Morley Experiment Light sent from S is split into two perpendicular beams by the half-silvered mirror at A. These two beams are then reflected back by the mirrors M1 and M2 and are recombined in the observer’s eye. An interference pattern results from these two beams. The beam AM1 travelled across the ether, whilst AM2 travelled with and against the ether.The times to do this can be shown to be different and so introduce a phase difference between the beams. When the entire apparatus was rotated through 90 °, a change in the interference pattern was expected. None was observed. The result of the Michelson-Morley experiment was that no motion of the Earth relative to the ether was detectable. M1 A S M2 Ether Wind  § Discuss the role of critical experiments in science, such as Michelson-Morley’s, in making determinations about competing theories From a hypothesis, predictions are made of what should happen if a particular experiment is performed.If the results are not in agreement with the prediction, the hypothesis is incorrect. As we have seen, the fact that a null result was found from this experiment showed the ether hypothesis to be invalid. This opened up a completely revolutionary view of space and time with the work of Einstein. William Kim HSC Physics Summary | page 14  § Outline the nature of inertial frames of reference Frames of Reference Frame s of reference are objects or coordinate systems with respect to which we take measurements. Position In maths, the Cartesian coordinate system is used and position is referred to the axes x, y and z.In experiments in class, the laboratory is the frame of reference. S S' r u r P v Velocity An object P travels with velocity v with respect to a reference frame S. Another frame S’ moves with velocity u relative to S. The velocity of P relative to S’ is v’ = v – u. Velocity thus depends upon the reference frame. Inertial Frames of Reference An inertial frame of reference is one that is moving with constant velocity or is at rest (the two conditions being indistinguishable). In such reference frames, Newton’s Law of Inertia holds. A non-inertial frame of reference is one that is accelerating.  § Discuss the principle of relativityThree hundred years before Einstein, Galileo posed a simple idea, now called the principle of relativity, which states that all steady motion is relative and cannot be detected without reference to an outside point. This idea can be found built into Newton’s First Law of Motion as well. Two points to be reinforced:  § The principle of relativity applies only for non-accelerated steady motion  § This principle states that within an inertial frame of reference you cannot perform any mechanical experiment or observation that would reveal to you whether you were moving with uniform velocity or standing still.William Kim HSC Physics Summary | page 15  § Identify the significance of Einstein’s assumption of the constancy of the speed of light In 1905, Albert Einstein proposed that the speed of light is constant and is independent of the speed of the source or the observer. This premise explained the ‘negative’ result of the MichelsonMorley experiment and showed that the ether concept was not needed. As a consequence of this ‘law of light’ it can be shown that ther e is no such thing as an absolute frame of reference. All inertial reference frames are equivalent. That is, all motion is relative.The laws of physics are the same in all frames of reference; that is, the principle of relativity always holds.  § Recognise that if c is constant then space and time become relative In Newtonian physics, distance and velocity can be relative terms, but time is an absolute and fundamental quantity. Einstein radically altered the assumptions of Newtonian physics so that now the speed of light is absolute, and space and time are both relative quantities that depend upon the motion of the observer. (Our reality is what we measure it to be. Reality and observation cannot be separated. Remember this as we proceed).  §Discuss the concept that length standards are defined in terms of time with reference to the original meter †¦In other words, the measured length of an object and the time taken by an event depend entirely upon the velocity of the obser ver. (This is why our current standard of length is defined in terms of time – the metre is the distance travelled by light in a vacuum in the fraction 1/299792458 of a second).  § Identify the usefulness of discussing space/time, rather than simple space †¦Further to this, since neither space nor time is absolute, the theory of relativity has replaced them with the concept of a space-time continuum. Space and time, not just space, are relative quantities).  § Account for the need, when considering space/time, to define events using four dimensions †¦Any event then has four dimensions (three space coordinates plus a time coordinate) that fully define its position within its frame of reference. William Kim HSC Physics Summary | page 16  § Explain qualitatively and quantitatively the consequence of special relativity in relation to: The relativity of simultaneity The equivalence between mass and energy Length contraction Time dilationThe Relativity of Simultanei ty (simultaneity and the velocity of light) Observers in relative motion will disagree on the simultaneity of events separated in space. The Equivalence Between Mass and Energy The mass of a ‘moving’ object is greater than when it is ‘stationary’ – it experiences mass dilation (covered later). Since c is the maximum speed in the universe it follows that a steady force applied to an object cannot continue to accelerate. It follows that the inertia, that is the resistance to acceleration, must increase.But inertia is a measure of mass and so the mass has increased. It is this increase in mass that prevents any object from exceeding the speed of light, because as it accelerates to higher velocities its mass increases, which means that further accelerations will require even greater force. This is further complicated by time dilation because, as speeds increase to near light speed, any applied force has less and less time in which to act. The combined ef fect is that as mass becomes infinite and time dilates, an infinite force would be required to achieve any acceleration at all.Sufficient force can never be supplied to accelerate beyond the speed of light. If force is applied to an object, then work is done on it – energy is given to the object. This energy would take the form of increased kinetic energy as the object speeds up. But at near light speed the object does not speed up. The applied force is giving energy to the object and the object does not acquire the kinetic energy we would expect. Instead, it acquires extra mass. Einstein made an inference here and stated that the mass (or inertia) of the object contained the extra energy.Relativity results in a new definition of energy as follows: E = E k + mc 2 where E = total energy, Ek = kinetic energy, m = mass, c = speed of light When an object is stationary, it has no kinetic energy, but still has some energy due to its mass. This is called its mass energy or rest ener gy and is given by: 8 -1 E = mc 2 where E = rest energy (J), m = mass (kg), c = speed of light (3 x 10 m s ) William Kim HSC Physics Summary | page 17 Implications of Special Relativity: To measure speed we need to measure distance and time. If c remains constant, then it follows that distance (length) and time must change.Space and time are relative concepts. Length Contraction (the Lorentz-FitzGerald Contraction) The length of a ‘moving’ rod appears to contract in the direction of motion relative to a ‘stationary’ observer. l = l0 1 ? v2 c2 where l is the moving length, l0 is the ‘rest’ length (that is, the length as measured by an observer at rest with respect to the rod) and v is the speed of the rod. Time Dilation Time in a ‘moving’ frame appears to go slower relative to a ‘stationary’ observer t= t0 1? v c2 2 where t is the observed time for a ‘stationary’ observer and t0 is the time for an observer travelling in the frame. 0 is called the proper time (this is the time measured by an observer present at the same location as the events that indicate the start and end of an event). Mass Dilation The mass of a ‘moving’ object is greater than when it is ‘stationary’. m= m0 1? v2 c2 where m is the mass for a ‘moving’ object and m0 is the mass for that object when it is ‘stationary. ’  § Discuss the implications of time dilation and length contraction for space travel The relativity of time allows for space travel into the future but not into the past.When travelling at relativistic speeds (0. 1c or faster), relativity influences the time that passes on the spacecraft. Astronauts on a relativistic interstellar journey would find their trip has taken fewer years than observed on Earth. William Kim HSC Physics Summary | page 18 Core Topic Two: Motors and Generators 1. Motors use the effect of forces on current-carrying conductors in magnetic fields  § Identify that moving charged particles in a magnetic field experience a force Charged particles moving in an external magnetic field will experience a force.If the moving charged particles are flowing through, and confined within, a conductor that is in an external magnetic field, the conductor will also experience a force. This effect is known as the motor effect. F = qvB Use left hand â€Å"FBI gun† An example: Van Allen Radiation Belts The Earth’s magnetic field captures charged particles from the solar wind (low energy) and cosmic rays (high energy). The charges are force to spiral along the field lines accumulating into two doughnut-shaped belts of â€Å"radiation† called the upper and lower Van Allen radiation belts.William Kim HSC Physics Summary | page 19  § Discuss the effect, on the magnitude of the force on a current-carrying conductor, of variations in: The strength of the magnetic field in which it is located The magnitude of the current in the conductor The length of the conductor in the external magnetic field The angle between the direction of the external magnetic field and the direction of the length of the conductor †¦The force is proportional to the magnetic field strength, B †¦The force is proportional to the current, I †¦The force is proportional to the length, L The force is at a maximum when the conductor is at right angles to the field, and is zero when the conductor is parallel to the field. The magnitude of the force is proportional to the component of the field that is at right angles to the conductor. F = BIl sin ? William Kim HSC Physics Summary | page 20  § Describe qualitatively and quantitatively the force on long parallel current-carrying conductors: Ampere’s Law Two parallel wires, each carrying a current, will exert a force on the other. This happens because each current produces a magnetic field (as in Oersted’s experiment).Therefore each wire finds itself carrying a current across the magnetic field produced by the other wire and hence experiences a force. Determining the magnitude of the force between two parallel conductors The magnetic field strength at a distance, d, from a long straight conductor carrying a current, I, can be found using the formula: kI B= d -7 -2 where k = 2. 0 x 10 N A The magnitude of the force experienced by a length, l, of a conductor due to to an external magnetic field is: F = I 2 lB or ? kI ? F = I 2l ? 1 ? ? d ? rearranged F II =k 1 2 l d F II =k 1 2 l d (Ampere’s law) I1 I2 If currents are in the same direction, then the conductors will attract. If currents are in opposite directions, then the conductors will repel. William Kim HSC Physics Summary | page 21  § Define torque as the turning moment of a force using: Torque is turning force. Its’ units are Newton-metres (Nm). ? = Fd where ? = torque, in Nm F = force, in N D = distance from rotational axis, in m F = BIl ? =BIld Rotat ional axis d ? = Fd  § Identify the forces experienced by a currentcarrying loop in a magnetic field and describe the net result of the forces b max ? = nBIA zero ? b Current Loops N I F = BIl ? =BIld ? = ? 1 + ? 2 = BIld + BIld = 2 BIld = BI (l ? 2d ) = BIA S ? = nBIA cos ? ? b (For each turn of the loop) Generally, ? =nBIA cos ? William Kim HSC Physics Summary | page 22  § Account for the motor effect due to the force acting on a current-carrying conductor in a magnetic field The motor effect Recall that charged particles moving in an external magnetic field will experience a force. If the moving charged particles are flowing through, and confined within, a conductor that is in an external magnetic field, the conductor will also experience a force.An electric motor is a device that transforms electrical potential energy into rotational kinetic energy.  § Describe the main features of a DC electric motor  § Discuss the importance of the invention of the commutator for devel oping electric motors  § Describe the role of the metal split ring and the brushes in the operation of the commutator Anatomy of a DC motor – Permanent magnets: provide an external magnetic field in which the coil rotates. As the magnets are fixed, they are known as the stator. – Rotating coil: carries a direct current that interacts with the magnetic field, producing torque. Armature: is made of ferromagnetic material and allows the coil to rotate freely on an axle. The armature and coil together are known as the rotor. The armature protrudes from the motor casing, enabling the movement of the coil to be used to do work. – Commutators: reverse the current of the coil every half turn to maintain consistent direction and torque. It is a mechanical switch that automatically changes the direction of the current flowing through the coil when the torque falls to zero. – Brushes: maintain electrical contact of coils with the rest of the circuit.The developmen t of DC motors outstripped that of AC motors and generators for two reasons: – Voltaic batteries could supply power – They could use powerful electromagnets that were far stronger than permanent magnets The development of the commutator was important because it led to the development of modern electric motors and generators. It enabled motors to provide steady circular motion of a drive shaft.  § Describe how the required magnetic fields can be produced either by currentcarrying coils or permanent magnets The magnetic field of a DC motor can be provided either by permanent magnets or by electromagnets.William Kim HSC Physics Summary | page 23 2. The relative motion between a conductor and magnetic field is used to generate an electrical voltage  § Outline Michael Faraday’s discovery of the generation of an electric current by a moving magnet Faraday had found that 3 things are necessary to generate (or â€Å"induce†) an EMF (voltage supply): – A magnetic field (from some magnets or electromagnet) – A conductor (eg. wire or coil of wire) – Relative motion / change between the field and the conductor If the conductor formed a closed loop then an induced current would also flow. ire If this wire is dropped so that it cuts flux lines, then a voltage appears between the ends because electrons are forced to the right. They eventually stop moving because they create an electric field pushing them back. As long as the magnet is moving, an emf and current is induced. Faraday’s Law ? =? n ? where ? = induced EMF, in V n = number of turns on coil ? = change in ? = magnetic flux, in Wb = BA B = magnetic flux density (field strength), in T The induced voltage can be increased by: Increasing n: more turns on the coil Increasing B: use strong magnets Increasing A: use a bigger coil Decreasing t: go faster! B A = area of coil in m 2 ? = time taken for to occur William Kim HSC Physics Summary | page 24  § Define ma gnetic field strength B as magnetic flux density Magnetic flux density is the magnetic flux per unit area and is a measure of the magnetic field strength.  § Explain the concept of magnetic flux in terms of magnetic flux density and surface area ? = BA sin ? where B = magnetic flux density, in T A = area, in m 2 ? = magnetic flux, in Wb  § Explain generated potential difference as the rate of change of magnetic flux through a circuit The induced emf is proportional to the rate of change of flux through the circuit.See Faraday’s Law (above).  § Account for Lenz’s Law in terms of conservation of energy and relate it to the production of back emf in motors Lenz’s Law This is a supplementary law to Faraday’s Law. It says that any induced emf or current will have a direction that opposes the change that caused it. This is really just a restatement of the law of conservation of energy because the induced electrical energy has come from the thing that caus es the original motion. Eg. In a hydroelectric power station, the kinetic energy of flowing water is converted into electrical energy. NWilliam Kim HSC Physics Summary | page 25  § Explain that, in electric motors, back emf opposes the supply emf Back emf Back emf is generated in any coil that experiences changing B fields, even though it is producing them. Note that back emf is frequency dependent – the higher the frequency of the changing field, the greater the back emf produced. Back emf is also produced in the rotating coil of a motor: – When the motor is spinning at its operating speed, back emf will have its max value, but†¦ – When the motor is just turned on it isn’t spinning yet so there is no back emf. This can lead to excessive current so the motor may be protected by using a â€Å"starting resistance† that limits current. When up to speed the resistor is taken out of the circuit. The coil becomes an electromagnet and generates an alternating B field BUT it also experiences the changing B field and generates its own emf that opposes the applied emf.  § Apply Lenz’s Law to the production of eddy currents Eddy Currents – are induced currents (usually unwanted or unintended) in two-dimensional conductors (eg. sheet metal) or three-dimensional conductors (eg. a block of steel).Sometimes it is necessary to design against them. Eg. the core of a motor is made of soft iron, and is made of thin layers (laminated) to prevent eddy currents. Some devices rely on eddy currents to work: Electromagnetic braking – a moving conductor near magnets will slow down because the eddy currents oppose its motion. Electromagnetic switching – security ‘gates’ that are really coils with AC generate a high frequency B field. Metal in this field develops eddy currents that work against the field, slowing it down. A detector circuit picks up on this and sets off an alarm.Induction Cooktops- are a n application of Faraday’s Law. Instead of a heating element, this cooktop contains a set of coils with alternating current passing through them. This produces a changing B field above the cooktop. A metal saucepan placed on the cooktop is a conductor in the changing B field and therefore an electric current is induced in the base of the pan. The current heats the pan, and this heat cooks the food. Induction cooktops are approximately twice as efficient as a gas cooktop, but are expensive to purchase. William Kim HSC Physics Summary | page 26 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Movement of metal Eddy current loop 3. Generators are used to provide large scale power production in isolated areas and as a backup in emergency situations  § Identify the main components of a generator An electric generator (dynamo) is a device that includes all of the elements necessary to transform mechanical kinetic energy to electricity according to Faraday’s Law: – A magnetic field (provided by a set of permanent magnets); – A conductor (a coil mounted on an axle, so it can spin); – Relative motion (the coil is made to spin by some other form of energy). Compare the structure and function of a generator to an electric motor In fact, most generators are constructed just like a motor, however the flow of energy through them is different. Motor: electrical energy a kinetic energy Generator: kinetic energy a electrical energy  § Describe the operation of an AC and a DC generator EMF is generated in the coil and a circuit is completed to the outside world through ring connectors, just like motors. If standard slip rings are used then a dynamo naturally produces alternating current AC. I t E t Doubling the frequency of rotation doubles the maximum induced emf If a split ring commutator is used instead, then the direction of the current flowing from the coil is reversed every ? cycle. This produces a pu lsing type of direct current DC. + I t William Kim HSC Physics Summary | page 27  § Discuss the energy losses that occur as energy is fed through transmission lines from the generator to the consumer Analyse the effects of the development of AC and DC generators on society and the environmentEven good electrical conductors like copper used to supply electricity, sometimes through considerable cable lengths to towns and cities, generate substantial resistances. It follows that to minimise energy loss in the wires, the current needs to be kept low (heating losses vary as the square of the current). This is achieved by transmitting the energy at high voltages.  § Impact on society – Impact on environment – Positive Improved lifestyle Street lighting Electric trains Communication Computerisation of many systems eg. anking, stock market Industrial development a more jobs Lots of electric trains have reduced pollution from steam trains and made public transport more avai lable Electricity has replaced older, more-polluting technologies eg. electrical heating instead of coal burning in fireplaces – Negative Possible risk of cancer living near distribution cables Longer working hours Reliance on electricity leaves us vulnerable to systems loss due to electrical failure – – –Burning coal in power stations produces smoke and CO2 (a greenhouse gas) Nuclear power stations produce radioactive water & have a risk of nuclear accident Hydroelectric schemes redirect water away from river habitats Mining impacts negatively on environment Visual pollution of cables  § Assess evidence about the physiological effects on humans living near high voltage power lines 1979 study found children living near high voltage power lines appeared to develop a particular form of cancer. 997 study showed no evidence of an increase risk of childhood cancer at residential magnetic field levels. 1998 panel stated that EM fields should be considered â⠂¬Å"possible human carcinogens† and that there is â€Å"no conclusive and consistent evidence that EM fields cause any human disease. † William Kim HSC Physics Summary | page 28 4. Transformers allow generated voltage to be either increased or decreased before it is used  § Explain the purpose and principles of transformers in electrical circuits A transformer is a device that alters the voltage and current of an electricity supply.The AC voltage source produces an alternating current in the primary coil. This produces an alternating B field that threads through the secondary coil. The secondary coil now has: – Conductor – B field – Change and therefore generates its own voltage. If there is a closed loop then an alternating current will flow as well.  § Compare step-up and stepdown transformers Step-up transformers: increase voltage and decrease current Step-down transformers: decrease voltage and increase current  §Determine the relationship between the ratio of the number of turns in the primary and secondary coils and the ratio of primary to secondary voltage Vp = primary voltage (voltage in) Ip = primary current np = number of turns on primary coil Vs = secondary voltage (voltage out) Is = secondary current ns = number of turns on secondary coil Vp Vs = np ns If 100% efficient (this needs perfect â€Å"flux linkage†, usually using an iron core) then: Power in primary = Power in secondary ? V p I p = Vs I s ? ? Vp Vs Vp Vs = = Is Ip np ns = Is IpWilliam Kim HSC Physics Summary | page 29  § Explain why voltage transformations are related to the conservation of energy The Principle of Conservation of Energy states that energy cannot be created or destroyed but that it can be transformed from one form to another. This means that if a step-up transformer gives a greater voltage at the output, its current must be decreased: i. e. power in = power out.  § Explain the role of transformers in electricity sub-stati ons NSW power stations produce electricity with a voltage of about 23,000 V and a current of about 30,000 A.Unfortunately, this amount is too high to be sent through a cable. This is because it heats the cable causing energy loss. This is called joule heating and happens because: P = I2R So to reduce joule heating, the current must be reduced as much as possible with a step-up transformer. Additional transformers between the power station and consumer (in sub-stations) gradually stepdown the voltage, to 240 V by the time it gets to household users. This is because at high voltages, electricity can conduct through air, making it dangerous for use in the home. Discuss why some electrical appliances in the home that are connected to the mains domestic power supply use a transformer Most electronic circuits are designed to operate at low DC voltages of between 3 V and 12 V. Therefore, household appliances that have electronic circuits in them will have either a plug-in transformer or an inbuilt transformer to step down the domestic 240 V supply. These transformers also have a rectifier circuit built into them that converts AC to DC.TVs also contain a step-up transformer for producing the high voltages needed for the CRT.  § Analyse the impact of the development of transformers on society The development of the generator and transformer has allowed for the setting up of national power grids in almost every country, making that most convenient and flexible form of energy, electricity, accessible from many miles away. The transformer’s role is to step voltage up and down to make efficient transportation and distribution possible. William Kim HSC Physics Summary | page 30 5.Motors are used in industries and the home usually to convert electrical energy into more useful forms of energy  § Describe the main features of an AC electric motor AC induction motor: – The rotor – end rings short circuit non-ferrous rotor bars, that is sealed i. e. no e xternal connections at all (usually a â€Å"squirrel cage†). Encased in a laminated iron armature. – The stator – surrounding electromagnet. – Connection to stator – the surrounding electromagnet receives the AC. In an AC induction motor, the principle of operation is: 1. AC to surrounding electromagnet, which†¦ 2.Produces an oscillating (rotating) B field, which†¦ 3. Induces a current in the rotor, which†¦ 4. Turns the rotor into an electromagnet that†¦ 5. Tries to oppose the field being generated by the stator. 6. The stator and the rotor push against each other (using their B fields), which†¦ 7. Causes the rotor to turn! Brilliant! AC (synchronous) motor: – A rotating coil – Surrounding magnets – Connection to coil via slip rings (commutator for DC motor)  § Explain that AC motors usually produce low power and relate this to their use in power tools Power is the rate of work. Work is done when ener gy is transformed from one type to another.Induction motors are considered to produce low power because the amount of mechanical work they achieve is low compared with the electrical energy consumed. The ‘lost power’ of induction motors is consumed in magnetising the working parts of the motor and in creating induction currents in the rotor. AC induction motors are considered to be unsuitable for use in heavy industry because their low power rating would make them too expensive to run when performing a specific task. However, they are used extensively in power tools and electric domestic appliances where the loss of power is not economically significant. Explain the advantages of induction motors Advantages of AC induction motors: 1. Simplicity of design; 2. High efficiency (hence low maintenance – there are no brushes or commutators to wear out); 3. Relatively low cost William Kim HSC Physics Summary | page 31 Core Topic Three: From Ideas to Implementation 1. In creased understandings of cathode rays led to the development of television  § Explain that cathode ray tubes allowed the manipulation of a stream of charged particles Discharge Tubes – Investigation of vacuum tubes could not occur until good vacuum pumps had been invented.A vacuum tube is a glass tube fitted with an electrode at either end, and almost all of the air sucked out. – The positive electrode is the â€Å"anode†; The negative electrode is the â€Å"cathode†. When a high voltage is connected between the electrodes, an invisible ray travels from the cathode to the anode. They were called â€Å"cathode rays†. Cathode rays cause glass to glow green. – A discharge tube is a cathode ray tube with a vacuum pump fitted, so that the air pressure inside the tube can be varied. At different air pressures, different bright effects appear in the tubes e. . bands, striations and dark spaces. These are caused by cathode rays striking atoms in the air inside the tube. The atoms become excited then release photons of visible light – A beam of electrons travels from the cathode to the anode and can be deflected by electrical and/or magnetic fields. Anode Glass glows here Cathode  § Explain why the apparent inconsistent behaviour of cathode rays caused debate as to whether they were charged particles or electromagnetic waves In 1892 Hertz demonstrated that cathode rays could penetrate thin metal foils.This he believed supported a wave nature. In 1895 Jean-Baptise Perrin showed that cathode rays deposited negative charges on impact with an object, suggesting a particle nature. There was controversy over the nature of cathode rays – waves or particles. William Kim HSC Physics Summary | page 32  § Identify that charged plates produce an electric field If metal plates are separated by a distance and are attached to a power source, an electric field will be produced between them. E = V/d  § Describe quantitati vely the force acting on a charge moving through a magnetic fieldRecall that the force (F) acting on a charge (q) moving with a velocity (v) at an angle to a magnetic field (B), is given by: FB = qvB Where FB = magnetic force (N) q = charge (C) v = velocity of charge (ms-1) B = magnetic field strength (T)  § Discuss qualitatively the electric field strength due to a point charge, positive and negative charges and oppositely charged parallel plates. Describe quantitatively the electric field due to oppositely charged parallel plates ++++++++ If a positive charge is placed near another positive charge, it will experience a force of repulsion.A positive charge placed in a field will experience a force in the direction of the arrow. A negative charge placed in a field will experience a force opposite to the direction of the arrow.  § FE = qE Where FE = electric force (N) q = charge (C) E = electric field strength (NC-1) ———– William Kim HSC Physics Summar y | page 33  § Outline Thomson’s experiment to measure the charge/mass ratio of an electron Cathode ray particles ? v? B ? ? ? ? ? ? ? FM ? ? FE ? ? ? v? E ? ? ? J. J. Thomson’s Experiment – By fitting plates to his CRT, he could subject the cathode rays to an electric field.The rays deflected, proving that they were charged particles, not electromagnetic waves. – He noticed that the rays deflected toward the positive plate, proving that they were negatively charged particles. – By crossing electric and magnetic fields, Thomson was able to deduce the velocity of the cathode rays. By turning off the E field, the particles followed a circular arc caused by the B field. The magnetic force was acting like a centripetal force. mv qvB = r q v ? = m Br – 2 ? FM = FE qvB = qE E ? v = B Thomson adjusted the strength of the fields so that the particles were not deflected.By carefully measuring the strength of the fields, Thomson could calculate v. T homson had already measured B and worked out v. By measuring the radius of curvature r, he could then calculate q/m, i. e. the charge/mass ratio of an electron. q/m for these particles was 1800 times greater than for a hydrogen ion, the simplest known atomic ion. Thomson quickly compared the charges and found them to be about the same (though opposite in sign) Therefore mass for cathode ray particles was 1800 times smaller than hydrogen Therefore cathode ray particles were subatomic particles!This was the first discovery of subatomic particles They were later called electrons. William Kim HSC Physics Summary | page 34  § Outline the role in a cathode ray tube of: Electrodes in the electrode gun The electric field The fluorescent screen The Cathode Ray Tube Each CRT has a vacuum tube/chamber, a cathode, an anode, and a target. Electrodes in the electron gun The electron gun produces a narrow beam of electrons. It consists of a filament, a cathode and two open-cylinder anodes. The a nodes help to accelerate and focus the electrons.A ring shaped electrode – the grid – between the cathode and anodes controls the brightness of the spot by controlling the number of electrons emitted by the gun. By making the grid negative with respect to the cathode the number of electrons, and hence the brightness is reduced. The electric field Acts as a deflection system. It consists of two sets of parallel plates connected to a parallel plates connected to a potential difference. This produces an electric field between the plates. The Y-plates control the vertical deflection and the X-plates the horizontal deflection.The fluorescent screen The inside glass of the end of the tube is coated with a fluorescent material for example, zinc sulphide. When an electron beam hits the screen, the coating fluoresces and a spot of light is seen on the screen. The screen acts as a detector of cathode rays. Electrons Cathode Anode To plates and screen William Kim HSC Physics Summ ary | page 35  § Outline applications of cathode rays in oscilloscopes, electron microscopes and television sets The Cathode Ray Oscilloscope (CRO) Is an electronics diagnostics device because it can show a graph of how voltages vary over time.Deflection of the electron beam is achieved by two sets of plates. Horizontal plates cause vertical deflection while vertical plates cause horizontal deflection. TV Tube An electron gun again produces the electron beam. Coils are used instead of plates, however. Electric current through the coils produce magnetic fields that can deflect the beams quickly from side to side, and more slowly from bottom to top. In this way the beam scans the entire screen. By varying the intensity of the beam, a picture is built up. The picture is refreshed 50 times / second, which is too fast to be noticed by the human eye.The Electron Microscope Uses electrons instead of light. Their wavelength is 100,000 times smaller than visible light, therefore their reso lving power is 100,000 times greater. – A â€Å"sample† is placed inside the chamber (which is really the CRT) – The air is then sucked out – An electron gun produces the electron beam – Coils produce magnetic fields to focus the beam (â€Å"magnetic lenses†) – The beam scans over the surface of the sample – Detectors pick up the reflected and scattered electron beam, and from this information a 3 dimensional image is constructed  §Discuss the impact of increased understandings of cathode rays and the development of the oscilloscope on experimental physics The introduction of electronic control systems into all forms of science and industry has seen the cathode ray oscilloscope (CRO) become one of the most widely utilised test instruments. Because of its ability to make ‘voltages’ visible, the cathode ray oscilloscope is a powerful diagnostic and development tool. William Kim HSC Physics Summary | page 36 2.The r econceptualisation of the model of light led to an understanding of the photoelectric effect and black body radiation  § Explain qualitatively Hertz’s experiments in measuring the speed of radio waves and how they relate to light waves Recall: Maxwell’s theory of electromagnetic waves In 1864 Maxwell, through a set of four brilliant equations, predicted a range of invisible waves made up of an electric and magnetic wave that regenerate each other. The speed of these waves was calculated to be 3 x 108 ms-1 and probably included light.E v B Heinrich Hertz’s Experiment: (proving Maxwell’s theory) Performed in 1886, Hertz built equipment to generate and transmit EM waves with ? ? 1m. He also had a separate receiver (a loop of wire) located about 20m away. Spark gaps were included to show when high voltage AC was present in the transmitter or receiver. The receiver spark only appeared when the transmitter spark was present. Hertz hypothesised that the sparks set up changing electric and magnetic fields that propagated as an electromagnetic ave, as postulated by Maxwell. He showed that these were waves being transmitted because he could reflect, refract and polarise them. By measuring the frequency, he calculated v (v = f ? ) and it came out as 3 x 108 ms-1. These properties proved Maxwell’s theory and as they are also exhibited by light, Hertz was able to provide experimental evidence that light is a form of transverse electromagnetic wave. to induction coil < 1mm gap transmitter charged plates receiver William Kim HSC Physics Summary | page 37  §Describe Hertz’s observation of the effect of a radio wave on a receiver and the photoelectric effect he produced but failed to investigate Outline applications of the production of electromagnetic waves by oscillating electric charges in radio antennae Hertz observed that the transmitter spark was producing s