Changing police culture Essay

The New Zealand police for the last 30 years has faced an unfriendly and an unprofessional police culture that has infringed on both the rights of fellow police offices and those of the society as a whole. This culture of open and fear less sexual misconduct and harassment of women through rape and other forms of sexual assaults. Reports indicate that most of the alleged perpetrators of these violence are high ranking policemen like the police commissioner himself. In the year 2007, the police commissioner gave findings on changing the police culture to give confidence to the public on the utility of the New Zealand police. There rests several critical elements that could hinder successful implementation of the recommendations by Margaret Bazley commission. First and foremost, I think the time lapse when the New Zealand police had started committing these types of insults had created a different culture amongst them. Culture in this respect means a shared organizational values and beliefs as well as norms that guide the action of individuals. Most of it was concentrated within the police force itself with policewomen victims of their colleagues. This is a major critical point towards the implementation of the police culture change. It therefore needs to be taken on board to achieve results for the New Zealand police and their acceptable conduct. In addition to this, the tradition that what they used to do was right according to them it portrayd a major challenge to abandon such behaviors. Their socialization and mental orientation become a stumbling block to a swift adoption of a crime free police force. Changing a culture is a process that needs time and it goes in steps. The other challenge is engraved on leadership and the wide spread misconduct of the police force across all ranks up to the commissioner. This goes ahead to crimes committed in the vicinity of the police commissioner and no action is taken. This confirms that down to the juniors, the situation is incomparable. For there to be positive change, I think there must be a radical move that exempts none of the alleged victims. The biggest problem now arises on who among them arrests the victims. Organizational culture involves status assumption in organizations with the leaders being assumed to be role models. With the findings of the investigate magazine, it reaffirms that only top ranking police officers were the perpetrators of sexual violence against their colleagues. A police cover is the worst the police can ever trade with on matters of public interest. In most organizations, bureaucracy is the order and that this cannot be assumed neither altered. This is even terrible because it exist with the top ranking officers since they are the source if information to the public. The lack of a purely independent investigative body of handling police complaints against their fellow officers. It is very hard for the police force to investigate itself on matters of social injustice. Even the government itself cannot perform because it still has to protect the reputation of its workers. It is only a body with no vested interests that can give results on dealing with complaint of the police force. The formation of a body with powers to investigate past crimes committed by the police force meant that the current and the ongoing were lawful to be put on hold awaiting investigation. The long procedural process of going back to 1980s up to 2007 gives the police a lot of confidence in terrorizing their colleagues due to the lack of immediacy in handling the allegations that arise. This is because culture unites people psychologically and includes a mission to meet. The threats to successful implementation of the recommendation is the diversity of offenses by the New Zealand policemen. Most officers are alleged to have committed several offenses. Dewar for example was convicted of four charges. It calls for the police commissioner to take radical steps in resolving the conflict since he is part of the problem. None of the junior police officers can accept to be prosecuted unless the police commissioner starts. Based on their previous culture it is hard for them to break the already held norms. It even goes further such that those officers convicted of crimes threaten to resign then it becomes hard to eradicate the culture. The formation of the â€Å"independent complain authority† cannot achieve if the police are not willing. Who will report those cases if the police themselves are already held in one culture? The police commissioner, Mr. Howard Broad was forced to respond to his own allegations of misconduct. He was affected positively and negatively as a leader. On the positive approach, he must have felt challenged that as a role model he had failed his juniors. The best was to try to avoid such suspicious allegations and promise to take responsibility of implementing the entire culture change. The trait theory puts it clearly that leadership is founded on personality. As a human being like any other and having been in a situation of an engraved culture over along time makes him fall in some uncalled for mistakes. However, his colleagues look at him like a teacher. He is very willing to a successful implementation of the recommendation though in a challenging environment. The police commissioner need to take his allegations of his misconduct and reaffirm his colleagues that he is ready to lead like a an example. Leadership is situational so he needs to work hard and give results on culture change. The greatest work ahead of the commissioner is to ask for corporation from the rest of the police. The government has the duty to get a competent person to lead the culture change in the police if Mr. Broad’s efforts are declared inconsequential. Mr. Broad as a leader is fully committed to preserving the reputation of the police however he may be thought of having committed a social misconduct. He says that his role as a police commissioner is to cement the reputation for performance and integrity within the police. This shows how much confident he is in dealing with the scenario. On the other hand, the allegations made on the police commissioner affects his ability negatively. Being the head, many of his junior officers may not take the initiative to listen to his advice. Such will divide the police to those who are loyal to the commissioner and those who are the direct opposite of his commands. This is likely to make work hard for Broad in implementing the recommendations. The inability of Mr Broad to take any action on a pornographic movie shown in his house shows how he is covering his friends. This is likely to persist with other high ranking officers not unless his case brings justice to the aggrieved parties. Here Broads ability is depicted as a failure and even leading the culture change may be hard for him based in people’s knowledge of his behavior. Regarding his personality as the lead team in the culture change, Mr Broad has two wars to fight. First, as the police commissioner he has the role of being an example to the whole New Zealand police. They are supposed to view him as a symbol of unity and service to protect the people of New Zealand. On the other hand, he has the duty to protect the reputation of the whole force on the public and give confidence to the public on their commitment to serving them. From the case leading culture change in New Zealand, there are lessons on the issues of managing culture change. Several issues need to be taken into consideration in the process of reforming persistent behaviors. The interest of reforming the police should be based in recognition of collective attitude of the organization as a whole and sideline the attitude of individual officers. The police need to find evidence on misconduct by some police officers and legally deal with officers condoning inappropriate sexual activity. The New Zealand police management lacked inappropriate policies, procedures and practices to deal with unending cases of sexual misconduct. This encompass the unavailability of standards of work amongst the front line staff. This is a shorcoming of many organizations. According to the inquiry done by Bazley, it found that standards varied across police Districts. This inconsistency resulted to the unavailability of procedures to deal with them. To address this, there needs to be drafted code of conduct for sworn police officers. The quality of investigation is vital in handling complaints against police officer’s. The complaints process on the police should be made public top enhance public confidence on the police. Prompt handling of the complaints is vital in radically driving the culture change. However, the force lacks resources to publicize its findings. The government of New Zealand has the duty to invest in the Public Complaints Authority for it to perform its duties. Changing culture of a police force is a process that also involves sustaining public confidence in the police. Police officers need to adhere and demonstrate standards of ethical and moral behavior. The police management system should comprise technocrats in administration who understand culture and organizational leadership. The management has to portray competence in handling police matters and maintaining a culture that supports police standards. This kind of management is supposed to break the strong bonding amongst the police which hinders them investigate their colleagues. The issue of on duty an off duty remain a problem among the New Zealand police. According to leadership theories, a leader remains a leader to at all costs and that he has a duty to those he leads. With such concerns, the male dominated force needs to view the work of the police to be a full, time job with responsibilities to meet. This operates by enhancing public confidence on the police.

Gender Roles in Society Essay

What is gender role? Gender roles can be linked closely to the Bible as the relations between men and women as both intuitive and sensual. Biologically gender is not determined; however, as a result of sexual characteristics of either men or women, it is established socially. According to the Food and Agriculture Organization of the United Nations gender is a central organizing principle of societies, and often governs the processes of production and reproduction, consumption and distribution. Gender issues focus on women and on the relationship between men and women, their roles, access to and control over resources, division of labor, interests and needs. Gender relations influence family well-being, household security, planning, production and many other aspects of life including the way we think or feel according to one’s gender. For this reason the definition of gender role today should be revised and predefined because the meaning it once had is no longer comparable with the Bible. Many countries have experienced huge turmoil and revising of its traditional gender roles within the last generation. These changes in gender roles affect the home, the workplace, and the school, plus they affect all walks of life to some degree. Gender role is a commonly discussed subject in society and many may argue about the true role of a man or a woman. Society and culture are also very important in relation to this subject. This means different societies and cultures may produce children and later, grown men and women, who have quite different views of a man or a woman’s place in the world around them, often determined by their culture’s gender stereotypes. Gender roles are attached to persons according to their gender. So, what are men’s and women’s roles in society? Should they be equal or do they have well defined roles they should play? In this day and age, people like to be intolerant by attempting to make the two sexes equal. Most people feel that it is unfair to say that women can do certain activities better than men and men can do other activities better than women but God actually made men and women differently and has given them different roles in life and society. God has made men and women to fit certain roles He has defined. The Bible talks a lot about God’s roles for men and women. Genesis, the first book of the Bible, talks about Creation and how sin entered the world. When God created everything, it was perfect and good. Right after Adam and Eve disobeyed God, God kicked them out of the perfect place he had made for them called the Garden of Eden. Genesis 3:16-19 says: â€Å"To the woman He said, ‘I will greatly multiply your pain in childbirth, in pain you shall bring forth children; yet your desire shall be for your husband, and he shall rule over you. Then to Adam He said, ‘Cursed is the ground because of you; in toil you shall eat of it all the days of your life. Both thorns and thistles it shall grow for you; and you shall eat the plants of the field; by the sweat of your face you shall eat bread’. This is God’s first example of roles to women and men. It was meant for men to take care of land and work it for food to provide for his family and women would bear children and take care of them and raise them while their husband worked. Again, a man and woman’s role is well defined in a home. They are both made for each other and to grow strong as one. A woman has quite a unique role to fill. She is made as a companion for her husband because without a wife a man is alone and she is the only one who can provide the companionship needs. She should give her husband affection because he needs it just as she needs it also and only she may know the husband in such a way to provide the kind of affection he needs. A wife is there to give physical needs because God made man and woman to rely on one another. Also a woman should bear children for her husband to make a family that they can all love and appreciate. Most mothers spend more time with her children and her influence on their character development is great because they see her the most. Lastly, every woman should be a keeper at home and this requires diligence and the kind of care only women can provide. It is a place of honor among God and His people. â€Å"A woman should be a guard, and ruler and keeper of the affairs of the home† (Prov. 31:13-15). There is nothing wrong with a woman working, as long as it is done in the right way it is honorable. All women, whether married or not, can look to the worthy woman for guidance for living godly lives. In God’s pattern we do not see slavery, but freedom, honor, and true beauty. However, all women shall strive to fulfill their God given roles in their own families, so as to gain honor for themselves, for their families, and for God. In addition, a man’s role in society differs quite differently from a woman. The man is the key to making the family work the way God intended. God puts the responsibility of having a Biblical family on the man. On top of that, men are under a lot of job pressure because of the failing economy which makes it harder to provide for the family. Many men never had a role model in their home. There should be Godly men helping their off springs to become who they ought to be for the glory of God. Men should love their family as Jesus loved the church; he is to also love the members of his family as he loves his body. He is to nourish it. He is to cherish it. He is to take care of it. That’s the way God wants a man to love his family. Eph. 5:23 says, â€Å"For the husband is the head of the wife, even as Christ is the head of the church and the Savior of the body. † Notice that it didn’t say the head over the wife; it said the head of the wife. It is not dictatorship. A man is not the dictator in the family but the man is to protect and provide for his family. Being a good provider is not enough as men have a spiritual responsibility. They should get their family in church each Sunday and take every opportunity to help them learn about Jesus Christ and to grow in their relationship with Him. Men should obey the word of the Lord and ask the Lord to help him be the man he should be. Many of men have failed to lead their family like they should. However, if he is the man, the father, the kind of husband God wants him to be, and if he lifts his family to be everything God wants them to be, one of these days he will reap a good harvest in his children. However, the shifting of gender roles in the past thirty years has been huge. It has happened so quickly that men and women are still trying to sort out what the new roles and rules mean to them although women are no longer expected to be the keepers of the house, in reality, they are in most families and although men are generally open to the successes enjoyed by the women they share their lives with, some still find it hard to celebrate a woman’s triumphs because they feel it attenuates their own. Even though the Bible clearly states the role of a man and a woman many individuals may argue this because the Bible was written a long time ago and they feel such implications do not apply anymore. Yet, the Bible is the word of God and his word is always right and should be abided by no matter how we may feel. Historically, it is important also to note that cultural differences flourish in the emphasis of one’s gender role and in certain societies such assumption in accepted gender norms can also play some part in the definition of gender identity. It will take time to sort out all the assumptions of the changing gender roles of individuals, but new expectations should result in better lives, better relationships, better schools, and better workplaces.

Level diploma for children and young peoples workforce

Levels diploma for children and young peoples workforce BY tarsal 2345 SSH 31 : Promote communication in health social care or childcare and young people's setting. 1. 1 Identify the different reasons people communicate The people communicate with each other and the varied methods of communication; how communication affects individuals and groups. Communication not only affects the professionals but the children and the relationships between the various people linked to the work place setting. People communicate with each other on a regular basis.This is a key skill acquired room birth, a skill dominant in humanity since the beginning of time. It is a vital survival skill acquired learned enhanced and practiced to make perfect. The most basic of which is speech and body language. Communication is a tool with which we exercise our influence on others bring about changes in society, in ourselves, In our attitude and in our environment. Through communication we can motivate the people a round us and can establish and maintain relationships. Communications make up a major part of our daily active life; and are a social requirement to mingle via communication.It Is a social activity to verbally communicate, correspond by reading writing or even body language! Communication Is the giving and receiving of information. Communication Is not specific to methods which speech Is relayed such as writing or reading but It Is refined by caste, culture, and education. When people live in/belong to a certain society or caste or have similar educative backgrounds. This contributes to their mindset and behavior and leads to better understanding of each other and In cases of different mindsets- creates misunderstanding. In this case the attitude and understanding and background of the person with whom weInteract with our communication skills would seem to be Imperfect and Ineffective. Some reasons of communication 0 To persuade 0 To provide and share Information/ knowledge 0 Ask qu estions 0 Express emotions 0 Maintain and promote good relationships that are affective In personal social and professional levels 0 Good flow of Information Ensure people know their roles and responsibilities Make sure rules and regulations are carried out Work together as a team Express wants and needs Negotiate and lease with others Interaction Avoid problems and misunderstandings place.Love understanding sharing and caring for each other all build a better society, unity; the core of which is strong communication. In a work setting communication is very important as it is the strongest factor we have to build and develop a relationship between ourselves, the children, their parents and our co workers. By being an affective communicator it helps to promote and create a positive working environment.In an establishment where we work as a team communication is important to keep up the group spirit, knowledge about what is happening whilst working with children It is vital to also co mmunicate with other professionals as well such as Doctors nurse's parents school teachers, social workers there co workers police men fire men etc So it is important that the rest of the team is communicated the information to as well 1. 2 Explain how communication affects relationships in the work setting.Information needs to be passed on to the relevant people keeping in mind the necessity of information to safeguard the internet of children and also protecting them and us as their Careers. I work on a need to know For example whilst I was out during school run time. My assistant was at home. I got a text from a parent that someone else would be coming one hour early than normal to pick up the child. Due to network issues I couldn't call the assistant.So had to call the parent to tell the person to wait till I got back as I needed to discuss something, also career at home had no idea what was happening, thereafter that day I had a briefing with the parent that I will have to have at least twenty minutes notice before pick up, even if assistant is at home; As I may be out. They will have to wait until I return. Also I had to have a briefing with my assistant that should any of the parents knock on the door and they are unaware they must wait till I return as I may need to talk to the parents/ relay mom information etc.In this way I kept my parents and assistants aware that we need to make sure things are in order. Otherwise things can go out of hand and I need to maintain safeguarding for everyone. I made sure I was clear and precise and to the point and made sure they all understood the importance of the instructions. I felt that as I was the main role leader I should communicate my wants and needs clearly so that the other people working under me will understand the rules and regulations. Also the set out rules and regulations need to be fair and Just- not biased.So the relationship between co-workers will be a happy one and an easy environment where the e nvironment in smooth. With clear understanding colleagues would support each other and this is very vital for a healthy setting. I felt that I kept a professional and friendly approach during my day. At times taking on Jobs where I felt the assistant needed more help made them realize that we are a team not a boss against their employee. In a work environment it is also important to have reviews from parents or co workers that will help improve the setting, so we can reflect on our reactive and take action to enhance it.Another reason why it is important to convey information to one colleague to another is the fact that some children have allergies. Worker did not know about it or didn't know how or why it is triggered, the child could be in danger. This affects the child's safeguarding rights and proper training for this was required and full information needed to be shared to protect both the child and the career from a difficult and hazardous situation. If the co worker was absen t/away they need to know if something new has happened to make sure they are up to date.I held a session with the assistant, the parent and the nurse involved with the child's treatment till date. And was given a full training session on how the practical parts of the allergy is dealt with. Observations are an important way to communicate information even for personal settings. Sometimes I am working alone. Doing paperwork helps to structure learning goals and objectives aiming for higher, knowing the child's potential and aiming to develop any under developed areas.If we communication with children and young people: we need some key skill to make our bobs and skills more competent 0 Being patient= having the ability to control our selves when there is trying situations 0 Listening skills= listen to and understand the child/Rene needs as much as possible 0 Remembering= names, personal preferences special things to them to make them feel like they belong and that this is a place wher e they are part of a small family 0 Body language = making sure our body language and posture is positive so the children can positively develop 0 Maintaining a good eye = when we talk to children make eye contact so they are aware that the conversation is for them and they are the individual it is aimed at 0 Sensitivity = using word carefully selected 0 Showing warmth love caring, understating, sincerity positive values of others etc 0 Safeguarding = making sure that all their physical and mental interests are always priority. Confidentiality = making sure we do not tell others about what is happening in our settings.So children's information is kept safe For example In my experience I found that sometimes information can be misinterpreted, such as one day I had arranged for a parent to come and meet me at the library, for a session where I would read with the children and she would also articulate with the children. As I had mentioned very briefly that I would be taking them to li brary A; but she had thought it was library B and went to a different library. However we resolved the issue as soon as I realized and I rerouted to the second library. Luckily there was a telephone conversation in which I had picked up from her that she was in library b and without putting any blame on either side met up at library b instead. Parent realized the misunderstanding and we made sure that in future we will be clear of exact venue as there are a few libraries nearby.

International Trade Project Essay Example | Topics and Well Written Essays - 750 words

International Trade Project - Essay Example In this the world price is $1 which is way below the domestic price of $3. Hence, at $1 domestic supply falls to 1, however quantity demanded in the domestic market rises to 16. This takes place primarily because of the inverse relation of quantity demanded and the direct correlation of quantity supplied with price. Assuming that there are no transport and other costs, domestic supply and demand takes place according to the world price. Since world production is infinite, at $1 the quantity sold will be 16. c. Assuming that free trade takes place i.e. there is no tariff laid on the goods imported from outside the domestic country; the equilibrium price stays at $1. Quantity supplied domestically is 1 however quantity demanded domestically is 16, which means there is a gap of 15 units of production. This gap is bridged by importing 15 units of the product from the world market. Hence, the output produced by domestic producers is 1 and that by the foreign producers is 15. Since the domestic price is higher than the world price and the country is an importer of the good, this implies that the rest of the world has a comparative advantage in the production of the good. The country is thus a net importer of the good and thus domestic consumers of the good are better off since they have to pay a lower price. d. Despite all the benefits of free trade, barriers to free trade do exist. Tariffs are excise taxes imposed on imported goods. As a tariff of $1 per unit is imposed, on one hand it raises the world price to $2 and hence the quantity demanded falls to 11 from 16 and on the other hand, the quantity supplied rises from 1 to 4. The gap between domestic supply and demand falls from 15 to 7. Hence, under $1 tariff situation, a total of 11 units are sold at $2. Tariffs are imposed primarily for protecting the domestic market. As already seen, the major and immediate impact of tariff is the rise in the price level. Since price is inversely

Pseudoscience and Astrology Essay Example | Topics and Well Written Essays - 750 words

Pseudoscience and Astrology - Essay Example The scientists are willing to admit that only a part of traditional astrological doctrine is scientifically based: among them the astronomic knowledge about the planets movements; classification of people’s psychological states, character and behaviours; professional psychological terminology, etc. Trying to prove that astrology is pseudoscience, the scientists in their critical works often rely upon the results of various statistical research. There have been statistical research that traced the lives of people who were born on the same day and time, and the results of this research have shown that there is no connection or coincidence between them. Especially well known are the works of Michel Gauquelin basing on the biographies of famous people that have shown that there is no correlation between a person’s character and profession, on the one hand, and their astrological parameters, on the other. There have been other experiments conducted by M. Gauquelin: Other tests show that it hardly matters what a horoscope says, as long as the subject feels the interpretations were done for him or her personally. A few years ago French statistician Michel Gauquelin sent the horoscope for one of the worst mass murderers in French history to 150 people and asked how well it fit them. Ninety-four percent of the subjects said they recognized themselves in the description. (The Universe At Your Fingertips, 2001-2009)

Changes in Apple's Supplier Code of Conduct Essay

Changes in Apple's Supplier Code of Conduct - Essay Example At Apple, we value our workers as really, they are the reason for our success. We, therefore, require of every supplier that transacts any dealings with Apple to exhibit genuine intention to protect the rights of our workers at all times. A maximum of 60-hour work week should always be observed. We ensure that our suppliers strictly follow this. This ensures that our workers are not over-worked, and hence they remain productive. By 2014, about 92% of our suppliers complied with this. We are custodians of human rights as well. This is seen in our use of conflict-free minerals in our products. Suppliers affiliated with Apple are usually held accountable to hiring procedures that are ethical.For productivity, good health is key. That is why at Apple, we really care about the safety and health of our workers. In order to ensure that this is maintained, we have sought to train our management staff and workers. In an effort to assure that safety and good health is maintained, we launched a bout 870 projects in 2014 to improve conditions at the places of work. This was done through the Environment, Health, and Safety (EHS) Academy. We have also come up with a comprehensive mapping program that aims to make steadfast our chemical management functions.We have great regard for the environment at Apple. That’s why we ensure that our products and services are environmentally conscious. We are doing all we can to ensure that the natural resources that have been bestowed upon us are well conserved.

Music history term paper Example | Topics and Well Written Essays - 1500 words

Music history - Term Paper Example The technical aspect of rock music is not without social consequences. The intricacies of rock music are predominantly considered as genre for the male, and this has been reflected in the practice of rock music with the electric guitar in stage and studio. According to studies conducted by the music industry, even women who are adept at using computers and musical instruments are not skilled in using music software. Use of particular kinds of musical instruments in rock music has always been a subject of controversy. While on the one hand the instrument reflects a musician’s concept of self-expression, on the other hand it causes doubt in the minds of the listeners regarding the authenticity of music. However, since the origin of rock music, electric guitar has been inseparable part of this genre of music in terms of its sound and the loud body performances of rock performers (Frith et al., 13). Rock music is a popular genre of light music that has its origin in America in the 1950s. Today, rock music is known for its variations in styles, lyrics and soul. One of the most well-known figure in rock music is Bob Dylan who was born on May 24, 1941. He played a big role in popularizing rock music for more than five decades. In his long career, if there is one thing that has remained constant then that is change. Indeed, it is said that Bob Dylan gets into his car as one person and emerges from the car as another person. His life and style almost reflect the lyrics of his song â€Å"I’m not here, I’m gone†. It is the ability of Bob Dylan to maintain a constant change in his career is what makes him most adorable among his fans. When one visits his concert, it is likely that Bob will meet the expectations of the audience by playing fifteen songs and two or three encores, but there is also high possibility that the audience will be treated with one or two new songs (Yaffe, 18). Highway 61 Revisited is Bob Dylan’s sixth album that

Nuclear Non-Proliferation Essay Example | Topics and Well Written Essays - 2000 words

Nuclear Non-Proliferation - Essay Example Many theories exist on the 'why' and 'how' of nuclear proliferation such as 'classical realism' and 'neo-realism' but what is generally accepted is that the locus is external in nature. As per Fry, "If a state bids for hegemony, other states willform an alliance to contain and deter the expansion-revisionist states" (Fry 3). This is based on the assumption that states seek to, "maximize their power in order to survive in a competitive international system," (Ogilvie-White 44). Hence, nations who see a perceived threat to their national interests or in extreme cases to their very existence (as in the caser of Israel) seek to acquire a nuclear deterrent since "security represents the intimate challenge to a states survival (Ogilvie-White, 45). This theoretical debate is best exemplified by the arguments propounded by Scott D. Sagan and Kenneth N. Waltz in their book 'The Spread of Nuclear Weapons, A Debate' (New York: WW Norton and Company, 1995). This scholarly debate has two basic schools, one that views states as unitary, rational entities and the other which feels that proliferation occurs as an outcome of organizational interests. Both views have their merits and limitations as will be expanded upon. However, it is quite apparent that given existing geo-political realities, more and more states will seek to acquire nuclear weapon capabilities as a safeguard against nuclear blackmail. The first school of thought, led by Kenneth Waltz are the proliferation 'optimists' in that they feel that nuclear proliferation is not necessarily a negative outcome, and that contrary to popular belief, it may even have contributed to world peace. According to this theory of 'rational deterrence', "once more than one state has acquired a second-strike capability, war between the nuclear armed states is unlikely to occur, due to the fact that mutual destruction is almost assured" (Waltz 1990, 734). Waltz argues that near parity in nuclear weapon capability leads to a reduced probability of armed conflict on account of the prohibitive costs of waging war; unacceptable levels of mutual destruction; and lesser chances of miscalculation by the political leadership, since the ramifications such miscalculation would be catastrophic. This theory certainly gains some credibility when one considers that there has been no all-out war between two nuclear powers. However, Waltz qualifies this optimism by laying down certain pre-conditions that have to exist for stable deterrence. These are firstly, that "there should be no preventive war while a state is developing its nuclear capability; secondly, "both states must develop a sufficient second-strike force to retaliate if attacked first; and thirdly, "the nuclear arsenals must not be prone to unauthorized or accidental use" (Sagan and Waltz, 51). This position seems quite reasonable since nuclear wars are more likely in conditions of asymmetry, even though the asymmetry might be in terms of conventional military capability. It also reinforces the rationale of states seeking to acquire nuclear weapons capability in order to maintain the balance of power through nuclear deterrence. This would be particularly true of states which see themselves surrounded by inimical neighbors, as in the case of

The Progress Report Assignment Example | Topics and Well Written Essays - 1000 words

The Progress Report - Assignment Example Chinese Restaurants are facing direct and indirect competition. So, in order to stay and remain competitive in the market Chinese Restaurants should work on increasing the awareness of their products. In the case of Chopsticks Express, this restaurant is targeting only the small amount of Chinese consumers, who are the students of the State College. My efforts would be to make awareness of the Chinese foods in the market along with highlighting how the local customers could be attracted towards Chinese foods. The role of supervisor has been important for this project and I have been guided by my supervisor throughout the project and this has helped in improving the quality. I have been incorporating the feedback of the supervisor and will continue doing so. After receiving further feedback, the research would continue its steps for the submission of its final draft of proposal. Work Completed I have received the approval and feedback from my instructor about my research. The feedback included instructions of carrying out my research and his instructions have been helpful in improving the work. I have identified that Chinese restaurants are facing some direct competition from the other Asian and American restaurants. The draft proposal of the project was due from 10th June and after modifying my research according to the feedback received I submitted my final proposal in the third week of June with my final topic of Research Information of Chinese Restaurants in State College. My research included analysis of different Chinese restaurants. 13 Asian and 8 Chinese restaurants are located in State College Downtown. Among the Chinese restaurants, Chopsticks Express offers the authentic cuisine of Chinese. Chopsticks express, situated in the center of the state downtown, enjoys the advantage that it could attract more customers apart from the local Chinese customers. I have identified the reason why the restaurant has not been highly successful and the reason is that it does not influence other customers of the region. I figured out that majority of the people do not visit Chopsticks Express because of its unpopularity. When I have researched on it further, I identified the reasons why no one would want to visit a restaurant which does not have a welcoming environment. In the ending days of June I was supposed to work on the demographic part. Demography included the study of population and size. The study included sample size of 800 customers who received questionnaires; these 800 people were those who belonged not only to the area of downtown but also those who visit downtown. The questionnaire was also provided for the managers of the Chinese restaurants operating in the State college downtown. Information and awareness play an important role in marketing of the restaurant. The responses suggested that awareness of Chinese food in US was relatively low and only local customers like Chinese students preferred Chinese cuisine in US. For determi ning the possible solutions for the Chinese restaurants to attract larger number of customers I submitted my recommendations on 30th June. Work to be completed Through this questionnaire I will try to identify the tastes and preferences of the people.I will also appoint interviews with the managers of the Chinese restaurants where I will ask questions related to my study. I want to help Chinese

The Core Competency of the Company Case Study Example | Topics and Well Written Essays - 2500 words

The Core Competency of the Company - Case Study Example Brand strategies define buyer experience-through the products offered, the advertising messages conveyed, indeed through every interaction between an organization and a buyer-and through that experience buyers develop an understanding of brand differences (perceptions), form judgments about the value of brand differences (preferences), and create a logic for choosing among brands (brand choice strategies).We refer to strategies that teach buyers as market-driving strategies (Bearden et al 77). Because of the Japanese consumer's traditional focus on corporate reputations, Japan has been considered a tough market for individual brands. This rising importance of branding, segmentation, and positioning has created new opportunities. In addition to Asahi and Honda, other nimble companies are taking advantage of the changes in the market to identify and capture specific segments of the market. Given the need to balance corporate and product-level branding, Sharp is applying a variety of approaches. These range from the more traditional corporate branding to two-story branding to narrow individual brand positioning. Companies are also using more Sharp -style branding (Boone and Kurtz 72). High technology continues to have an intense attraction for consumers, who recently favored such products as wristwatch PCs flat-screen TVs, and satellite cellular phones. New product development in Japan used to be technology and shelf-driven. In this environment, Japanese firms developed an unparalleled capacity for rapid product innovations, churning out new products and variations at a breathtaking rate (Collis and Noda 5). Japanese companies continue to have tremendous capabilities in rapid product innovation. of new product launches is greater in Japan than in the United States. In other categories, such as household products, the number of new product launches relative to the size of the market is larger in Japan than in the United States. In a few categories, such as foods, Japan lags behind the United States in producing new products (Kotler and Armstrong 92). Core competencies of Sharp are unique approach to products and entrepreneur spirit, innovative and state-of-the-art solution. The choice criteria of Japanese consumers is complex and changing rapidly. The approach to such cross-sectional variability would be niche marketing. United States marketers would find segments of the market in which the company has advantages over rivals and concentrate on those markets. But because Japanese consumers have traditionally been hard to segment and consumer choices have changed quickly-and, in many cases, randomly- Japanese firms instead developed a "rapid fire" approach to marketing to deal with the tremendous variability of their markets (Kotler and Keller 62). 2.In what ways does being a Japanese company contribute to Sharp's success Traditionally, Japanese companies have focused on building large, ambiguous corporate brands, so the "what" of brand positioning has been very difficult to pin down. In a market perceived to be homogeneous, the "whom" of brand positioning has also been very difficult to determine. In effect, the "what" and "whom" of Japanese

Sigmund Freud Essay Example for Free

Sigmund Freud Essay Consequently, Watson proposed that psychologist should confine themselves to studying behaviour, since only this was measurable by more than one person. For Watson the only way psychology could be taken seriously was to emulate the natural sciences and become objective. Watsons form of psychology was known as behaviourism. In 1913, Watson was working in the field of animal psychology and thought that the term animals could include humans. Watson was not interested in the mental processes. He saw no role for the mind and consciousness. Watson thought behaviour was observable and therefore scientific. The mind and its thought processes were abstract and unobservable and therefore unscientific. Behaviourism was defined by Watson as the study of the association between a stimulus and a response. Ivan Pavlov (1849-1936) was a Russian physiologist studying the digestion of dogs, when he found that the laboratory dogs could be conditioned to salivate without food. This learnt behaviour was called classical conditioning. Behaviourism began with the study of animals and experiments were taking over from simply watching them in their natural environment. Thorndike (1911) was interested in human behaviour although he used animals for his experiments for ethical reasons. Thorndike used a puzzle box with a complicated set of pegs and pulleys and watched as the animals attempted to escape. Eventually though trial and error, the animal would manage to open the door and it was rewarded with food. So escaping from the box had become desirable. The animal would then be placed in the box again and after several repetitions the animal preformed the necessary response to open the door more quickly. Thorndike argued that the animal had learnt how to escape because of the reward. Thorndike called this the law of effect. If we like the consequences of our actions then the actions are likely to be repeated. This kind of learning was known as operant conditioning and was studied in more detail by B. F Skinner (1874-1949) Skinner reiterated Thorndikes law of effect in his experiments with rats. Skinners approach to psychology was scientific. His views came from Darwins theories of evolution. Skinner focused on the environment as a cause for human behaviour. He did not think people acted for moral reasons; he thought they reacted in response to their environment. A person might do a good thing not for moral reasons, but for the rewards received for the act. For Skinner the mental process is irrelevant. There is a key difference between classical conditioning and operant conditioning. Classical conditioning involves involuntary or innate behaviour such as salivating and fear responses. They can be elicited, which means you can do something that produces an involuntary response. Operant conditioning involves voluntary behaviours. Voluntary behaviours are those behaviours that cannot be made to happen. This means that you cannot get these behaviours until someone carries them out. Watson did a study in 1920 and it is a widely used example of how we learn. Albert was conditioned to show a fear response to rats that he initially liked and showed no fear. Watson used a hammer struck on a metal bar to make a loud noise. Albert showed a natural fear response to the loud noise. (Unconditional response) The bar was struck while Albert petted the rat. Eventually, Albert associated the loud noise with the rat and showed the fear response upon seeing the rat. (Conditional response) Watson claimed that emotional responses are learnt through conditioning. He concluded that environment shapes our personality and genetics play no part in our behaviour characteristics. There are ethical criticisms of the little Albert study, however the main criticism seem to be that when the data was examined it showed that it was quite difficult to condition Albert and the fear did not last long. They had to repeat the pairing often to strengthen the association between the loud noise and the rat. Although, the study suggests that it was easy to condition Albert, the data suggest that it was not that easy and not that clear cut. Social learning theory assumes that personality differences result from differences in the learning experiences. This includes learning from observing others in addition to operant and classical conditioning. For example in language acquisition, a child learns to talk by imitating the adults. For social learning to occur, one individual must acquire a new behaviour from another individual (the model) with no reinforcement required. For example, monkeys in the wild are afraid of snakes and display this fear with screeching and jumping up and down. Captive monkeys reared in a laboratory do not have this fear. Mineka and Cook (1988) studied how rhesus monkeys can learn this response. When lab reared monkeys observed the agitated behaviour of wild monkeys in response to a snake, they modified their behaviour to match the model. The monkeys seem to have learnt to display fear by watching the behaviour of other individuals. Bandura, Ross and Ross, (1961) set out to investigate whether children learnt, through observation to display aggression. Children aged between 3 and 6 years of age were split into two groups. One group were exposed to a non-aggressive adult model. The other group were exposed to an adult model behaving aggressively, both physically and verbally to a blow up Bobo doll. The model punched, kicked and hit the doll with a mallet while the children observed this behaviour. The children were then taken to a room containing non-aggressive toys such as crayons, cars, a farm set and aggressive toys such as a dart gun a mallet and a Bobo doll. The children imitated the model with verbal and physical aggressive behaviour towards the Bobo doll. The findings demonstrated that observation and imitation could account for the learning of specific acts without reinforcement. Classical conditioning can explain some of the aspects of human behaviour, especially natural fear responses. Taste aversion, phobias and Gulf War Syndrome can be explained this way. Classical conditioning has a wide range of applications in behaviour therapy and has been successful in treating phobias. However, it cannot explain the attainment of entirely new behaviours and it cannot explain all of human learning especially the diversity of human personality and characteristics. It does not take into account that humans are capable of insight learning and the results are achieved through reasoning, with no trial and error are present. Operant Conditioning can explain how children learn the sounds of words from adults. Nevertheless, it does not explain how children correct grammar, as parents do not reinforce grammar (Slobin 1975) Bibliography Brain C. (2000) Approaches and Methods. Nelson and Thornes Ltd. UK Jarvis M. (et el) (2000) Angles on Psychology. Stanley and Thornes Ltd. UK Atkinson R.L. (et el) An Introduction to Psychology. (1981) Harcourt Brace College Publishers. USA (Word count 2052) Beverley Fielden Access Psychology

The Strategic Role of HR in a State Government Essay Example for Free

The Strategic Role of HR in a State Government Essay In a growing number of organizations human resources are now viewed as a source of competitive advantage (Human Links, 2007). For human resource to be competitive, it entails competencies that are â€Å"obtained through highly developed employee skills, distinctive organizational cultures, management processes and systems† (Human Links, 2007). The presence of these distinctive competencies marks most of the high-performance organizations. But the need for such organizations is not limited only to the private sector. Government organizations, particularly state and local governments, â€Å"are becoming increasingly accountable for results and the cost-effective use of taxpayer money spent on programs and services† (TechRepublic, 2007). Government organizations are like businesses; businesses that may not be run for profit but rather are organized to meet a social goal in an effective and efficient manner (Mathys, 2006). Such said, â€Å"Government organizations must be responsive, use their resources well, and provide good value to the user and account ­ability to the taxpayer† (Mathys, 2006).   It is in this context that strategic human resource management has become just as important in the public sector. Strategic human resource management has been defined as ‘linking of human resources with strategic goals and objectives in order to improve business performance and develop organizational culture that foster innovation and flexibility’ (Human Links, 2007). The whole process of strategic human resource management includes the measurement of the impact of actions and decisions.   Pressures on governments around the world have contributed to the rising adoption of â€Å"performance management and measurement† – a focus on program and service outputs and outcomes, and on â€Å"managing for results† (TechRepublic, 2007). One method that has had significant demonstrated success to improve process efficiency, timeliness, and customer satisfaction in business is the balanced scorecard (Mathys, 2006). The Balanced Scorecard is a â€Å"performance measurement that seeks to combine strategic planning with performance measurement† (Rogers, 2007). Robert Kaplan and David Norton published works on the Balanced Scorecard in 1991 and considered four areas in assessing the effectiveness of an organization in meeting its vision and strategy. These four areas or â€Å"perspectives† include: Financial, Customer, Internal Business Processes, and Learning and Growth. According to Mathys, Kaplan and Norton’s model explains that visions and strategies are translated into objectives, measures, targets, and initiatives that answer the questions in each of the four categories: Financial, the main question is: â€Å"To succeed financially, how should we appear to our shareholders?† Customer, the focus is: â€Å"To achieve our vision, how should we appear to our customers?† Internal business process focuses on the question: â€Å"To satisfy our shareholders and customers, what business processes must we excel at?† Learning and growth category focuses on answering the question: â€Å"To achieve our vision, how will we sustain our ability to change and improve?† Essentially, this framework â€Å"balances the value of strategic inputs (leading indicators) with financial outputs (lagging indicators) to enable an organization to improve the way it plans, measures and communicates success† (Strategic Management Partners, 2007). It is now being applied by hundreds of successful organizations, in the public and private sectors, to align people, strategy and performance (Strategic Management Partners, 2007). In 1999, the State of Illinois embarked on a strategic planning initiative (SPI) to initiate change using the balanced scorecard (BSC).   The initial goals were performance management and public accountability, which required viewing the Illinois public as a customer whose opinion of government performance was of paramount importance (Lang, 2007). The State of Illinois translated its goals and strategy into different measures of success Financial, Customer, Internal Business Processes, Human Resources Systems Development (learning and growth). In this context, the Human Resources (HR) Department has a critical role in facilitating the whole process of instituting a comprehensive public governance system using this measurement system. People management is an important function of the HR Department and can play an important role in an organizations financial performance as well as the service it offers its customers (Yahoo! Answers, 2007). People management includes managing recruitment selection, turnover issues, employee benefits, and acting as an information resource in HR issues for the organization (Yahoo! Answers, 2007). First, it is important that the HR department views the state government as well as its constituency as its customer. The HR Department ensures that loyalty among employees towards the organization is intact and also that the final constituents or the general population of the state government therefore are benefited. Second, the HR department looks into the other departments within the state government and assesses their goals and strategies as well in contributing to the achievement of the primary goal of the state government. This can be viewed particularly on learning and growth concerns such as how the various capabilities of various employees can be built up and enhanced so they can very well respond to the goals of the organizations, among others. This entails for example employing a Training Needs Assessment (TNA) tool so that employee capabilities may be surveyed, consolidated and aptly tapped. Knowledge of employee skills, abilities and aptitude could save the organization from investing on capability building trainings that do not address the real needs of employees. Third, in terms of internal business process, the role of the HR Department is to â€Å"indicate how much each employee contributes to the organization such as revenue generated minus the cost of salary, benefits and training† (Yahoo! Answers, 2007). This basically looks into the productivity of the individual employee as well as the consolidated output of such individual productivity levels with which the HR Department also has that function to design a merit and rewards system to increase again such productivity. This is vital to keep the bureaucracy lean. Fourthly, in financial terms, the HR Department shall be able to perform a rationalized system of recruitment because it sees fit which employees to hire based on the scope of work and job specifications. Aside from recruitment, HR also could do regular employee performance evaluations so as to determine which employee has actually continually met the specifications of the job. Again, this saves the state government from unnecessary hiring of staff and checking of redundancy, among others, since the staffing needs of the organization has been streamlined. With the HR Department using these four perspectives, it helps the government administration to keep â€Å"track the value of activities (e.g. human resource development) which previously had not been audited effectively and had not been regarded as contributors to the bottom line (Strategic Management Partners, 2007). As in many private corporations, HR Departments of state governments shall have to use hard data in measuring performance. This can be done by linking â€Å"employee competencies with behavioral objectives to align job specifications, recruitment, promotion, appraisal, and reward systems† (Strategic Management Partners, 2007). A number of HR measures or benchmarks can be employed to check on performance and these include: â€Å"Applications per vacancy, Internal promotions, Hours training, Peer group reviewing, Cross-functional projects, Knowledge sharing, Employee turnover, Cost per hire, Employee satisfaction,† among others (Strategic Management Partners, 2007). The HR Department can also assist the various departments of the state government in targeting and developing milestones that keep its focus on the goals.   The goals of the state government must be cascaded to every department with the help of the HR Department. In the end, some of the following questions may serve to measure the four perspectives: Customer/Constituency. What services have been delivered to the constituents in order to secure their welfare and how do these relate to people’s expectations towards the state government? Learning and Growth. Have the skills and competencies of officers and staff have been upgraded and in what manner? Internal Business Processes. What desirable levels of effectiveness and efficiency have been achieved in serving the constituents? Financial Resources. What revenue generating options have been tapped and which government services have already been provided at a reasonable price? In all these, the role of HR should be to facilitate rather than dictate the targets and outcomes. Keeping the measurements simple allows it to be more understandable and adaptable. If it is not seen to be fully integrated with the business imperatives of the Chief Executive it will not be given the attention it deserves by operational managers (Strategic Management Partners, 2007). List of References Chaturvedi, Siddharth. October 2007. Strategic Human Resource Management. Retrieved October 2007 from http://www.humanlinks.com/manres/articles/shrm/htm. Lang, Sandra S.   January 2007. The CPA Journal. â€Å"Balanced Scorecard and Government Entities Moving Forward at the Illinois Department of Transportation. Retrieved October 2007 from http://www.nysscpa.org/cpajournal/2004/604/essentials/p48.htm. Mathys, Nicholas. February 2006. Managing for Performance Results Series 2006. â€Å"Using the Balanced Scorecard: Lessons Learned from the U.S. Postal Service and the Defense Finance and Accounting Service.† Retrieved October 2007 from http://www.businessofgovernment.org/pdfs/MathysReport.pdf Rogers, Martha. June 2007. â€Å"Balanced Score Card Usage in Local Government Audit Shops.† Retrieved October 2007 from http://www.governmentauditors.org/content/view/311/123/. Strategic Management Partners. January 2007. Briefing Papers: Using the HR Balanced Scorecard. Retrieved October 2007 from http://www.consult-smp.com/archives/2005/02/using_the_hr_ba_html. TechRepublic. October 2007. Whitepapers: Using the Balanced Scorecard to Improve State and Local Government Performance. Retrieved October 2007 from http://whitepapers.techrepublic.com.com/webcast.aspx. Yahoo! Answers. October 2007. What is Balanced Score Card in HR?. Retrieved   October 2007 from http://ph.answers.yahoo.com/question/index?qid=20070927202545AAwkQix.

Effects Of Child Prostitution Young People Essay

Effects Of Child Prostitution Young People Essay Prostitution refers to the act or practice of offering sexual services to another person in return for payment or other favors. Prostitution is illegal in most countries of the world but is still legal in some countries. Different countries treat prostitution and prostitutes differently and the legality of prostitution activities varies from country to country. In some countries, the governments prohibit prostitution and punish all people caught involved in these activities. In other countries, the governments are committed to abolish prostitution. Some allow prostitution but regulate its activities while in some other countries, there is decriminalization of prostitution and people carry out prostitution activities just like any other job. In any of these cases, prostitution is a crime and is associated with other crimes. Like any other form of prostitution, child prostitution is common in the world and children mostly enter into this business because they are forced by circumstance s or people especially their parents or guardians. Child Sex tourism is also common. In this type of tourism, tourists engage minors of the country they visit in sexual activity. People also traffic children across international borders for purposes of sexual exploitation. Both Child trafficking and sex tourism contribute to child prostitution in foreign countries. About 900, 000 children are trafficked across international borders each year and people hold them in brothels or in other places for sexual exploitation. The problem of sex servitude affects both male and female children. People prefer to practice child prostitution in foreign countries for various reasons. Child prostitution is a world problem that requires both national and international attention. Many factors lead to child prostitution in many countries of the world. These include misery, poverty, unemployment of either the child or the parent, human trafficking, dysfunctional family environment, deception, poor education, AIDS scare, drug abuse and addiction, incest, rape, early exposure of children to sexual activities, and internet. Some governments also use child prostitution through sex tourism to promote tourism thus gain foreign exchange. They do this either directly or indirectly. These governments are those that are struggling economically. They usually assume acts of child prostitution and thus allow this evil act to attract more tourists and boost their tourism industry. Internet and child pornography serves as a major marketing tool that promotes child prostitution. People post on websites the experiences about child sex in different places and the costs involved. They also share child pornography through such websites thus encouraging not only child sex tourism b ut also child trafficking for sexual purposes. Poverty ranks high as a major factor that forces children to be prostitutes. This is common in poor countries affected by poor economies and wavering politics. In this situation, voluntarily becomes prostitutes or their parents force them into prostitution to provide financial needs of the family. This is common in most developing countries. Lack of viable sources to support the rising needs of people in these countries makes the children vulnerable to such exploitation. The families in poverty-stricken areas also become easy targets for procurement agents who are seeking for children to sell them into sexual slavery in brothels or various homes in the world. Child labor in poverty-stricken areas also exposes the children to prostitution. When parents or other agents send children to streets to hawk items, they expose their children, especially female children, to sexual harassment and rape. Human trafficking and deception are other factors that cause child prostitution especially in foreign countries. Human trafficking is a criminal activity in which some people purport to send teenagers to foreign countries to work but end up becoming prostitutes in their new destinations. Some brothel owners or procurement agents sometimes deceive parents by paying them money and promising them that their children will work in domestic chores but these children end up in prostitution. The brothel owners control the childs activities and do everything they can to maintain those who help them earn a lot of money. Sometimes hard times hit and these children are deported back to their countries where they continue with their prostitution activities. Dysfunctional family environments also play an important role in forcing children into prostitution. Such children do not get sufficient parental care and wander around looking for places to find solace. Such children end up in night discos and in other places, which expose them to early involvement in sexual activities. In the end, these children end up trading on their own bodies in order to support themselves. Incest and rape generally changes the childrens outlook in life and make some children to give room for prostitution. Some children become rebellious and defiant of the instructions given by their parents and feel independent. They demand for freedom to do what they want with their bodies. This leads most of them into prostitution. Drug abuse by these children also aggravates the problem by subjecting the children to prostitution and making them compromise situations they cannot when they are in their sound mind. Some children also engage in prostitution due to pleasure and continue in it because of the pleasure they derive from these acts. Criminals organize the sex industry in the world and use children in prostitution for their own gain. The demand of young girls and boys in some countries also contributes to the growth of this problem as more children face trafficking to work in foreign countries as sex slaves. The increasing demand of foreign sex in many people aggravates this problem. Some customers also fear sexually transmitted diseases like AIDS and thus engage children in prostitution believing that they are of low risk. Poor law enforcement in other countries also aggravates this problem. Child prostitution is common in virtually all countries of the world. Pimps, brothels and other criminal networks collaborate to traffic about 900, 000 children across borders for sexual exploitation and servitude every year. This is not only the problem of poor countries but it is common even in rich and developed countries. Sex tourism also combines with child trafficking to make this lucrative business of child prostitution to flourish. People usually employ networks of small groups to carry out activities like recruitment, transportation, advertising and retail of trafficked children for the purposes of sex exploitation in foreign countries. These groups often achieve major success because they require little capital to start up and prosecution by the countries involved is relatively rare. The major sources and destinations of sex tourism and child trafficking for sexual exploitation in foreign countries include Thailand, Japan, Israel, China, Belgium, Germany, Bulgaria, Netherla nds, Nigeria, Italy, Brazil and Ukraine among others. Of these countries, Thailand and Brazil are the leading in perpetuating the business of child prostitution. Even though prostitution and child sex exploitation is illegal in Brazil, from 200, 000 to 2 million children aged between eight and sixteen years are forced into prostitution in this country (Charles, 2010). The children involved in prostitution face many challenges and there are many effects associated with this child prostitution. Mostly, the pimps and brothel operators direct the activities of these children and they do not give them freedom of choice. This makes the children to work against their wishes. They also rarely give these children rest from their work. The pimps also give the children little food and this coupled with the high amount of work they do makes these children weak and sometimes may lead to death of the children. Child prostitution is also economically unsound and causes the child moral and physical harm as well as psychological trauma. Those who use children in prostitution activities usually do not well address their health issues. The children also risk attack from many sexually transmitted diseases like AIDS, syphilis, meningitis, anemia, tuberculosis, and others. This further weakens the health of these children and some lead to their death. Because child prostitution is an illegal business, some brothel owners or pimps fear taking the children to hospitals for treatment or regular checkups. In case they suspect a disease in any of the children, these brothel owners employ quark doctors who sometimes prescribe wrong medication for these children. As a result, the children live with a load of diseases and other health disorders, which give them problems throughout their lives. Such children especially girls are forced to enter into early child bearing and sometimes, family responsibilities. This makes those schooling to drop out of school and thus become less equipped for the labor market (Ringold, 2000). The gi rls used in child prostitution are forces to carry out frequent abortions. Unqualified doctors who also use poor methods and equipment in wrong environments often carry out these abortions. This further endangers the life of the child and deteriorates the childs health. Child prostitution also causes a lot of psychological and emotional stress to the children involved in these practices. Children in this case lose their self-esteem and give up in life. Some of the children get permanent physical damage, which they unwillingly live with. Such children do not have any confidence to engage in any other work except crime related jobs. Child prostitution is also associated with other crimes like drug trafficking and abortions. The more they get involved in other crimes, the more their morals deteriorate. They live in constant fear of raids by people and the police. Thailand has the worst record of child prostitution in the world. Even though prostitution is illegal in this country, it still takes place publicly or privately and sometimes the government regulates it. Large international criminal syndicates traffic children from other countries to Thailand and/or sends some children to other countries to work as prostitutes. Sex tourism in Thailand also contributes substantially to the problem of child prostitution. People coerce children from the age of 10 years into prostitution or some parents sell their own children into sex slavery knowingly or unknowingly. (Sorajjakool, 2003; Pusurinkham, n.d.). Poverty plays a major role in engaging minors into prostitution in Thailand. The children used in prostitution in this country come from Burma, Cambodia, Laos, China, Russia, and Uzbekistan. Thailand also traffics children to Japan, Malaysia, Australia, Europe, Canada, South Africa, Singapore and Bahrain for sexual exploitation. The children are kep t in brothels, which are sometimes surrounded by electric fence thus making it hard for the children to escape. Pimps give the girls harsh treatment and brutally beat those who are not cooperative sometimes to death. Ending child prostitution in Thailand has been a challenge because of lack of commitment from most of the stakeholders and the Thai government. Currently, having sex with girls below fifteen years of age is illegal under Thai law. However, child prostitution still exists in Thailand due to corruption of the government and political leaders. This issue makes the government and political systems to overlook or minimize the problem of child prostitution. The offenders often bribe police officers and politicians to protect them against prosecution. Even though this is the case, the government is striving to do away with child prostitution. It is doing this in association with nongovernmental organizations and other international organizations. The concern is to end sex tourism in Thailand and prevent child trafficking both into and out of the country for purposes of sexual exploitation and servitude. Brazil, China, Nigeria and Zimbabwe also have notable cases of child prostitution in foreign countries. These are destinations for child trafficking as well as sources of children trafficked to other countries for sexual exploitation. Sex tourists also find these destinations appropriate for their activities. Child prostitution in most countries of the world is illegal but still there are many instances of child sex molestation. Most governments are committed to end this problem of child prostitution both in their countries and in foreign countries. There are also many of non-governmental organizations and international organizations involved in reducing the practices of child prostitution in the world. These organizations include End Child Prostitution in Asian Tourism (ECPAT), the International Labor Organization (ILO), the World Tourism Organization, and the United Nations Childrens Fund (UNICEF) among many other international, regional and national organizations. ECPAT is an international organization based in Thailand. This organization was founded in 1991 with the goal of eradicating child prostitution in the world. The organizations plan is to persuade governments to enact laws to protect children against both local and international prostitution. After the governments have enacted these laws, ECPAT then ensures that these governments enforce these laws. The organization also persuades parents through their local leaders not to sell their children into prostitution (Hancock, n.d). It also discourages sex tourism and convinces governments to accept extra-territorial laws that allow prosecution of foreign citizens who sexually abuse minors in the country where they commit the offence. This means that sex tourists who use children in any foreign country will face judgment in the country where they commit the crime while they are on their tour. Some other human rights organizations gives information to parents in poor, rural areas about the tr ibulations and molestations the children go through in the places they sell them. They do this by use of photos, videos, and/or radios. This is what takes place in Thailand. UNICEF is a United Nations organization concerned with the welfare of children. The organization works in many countries to help vulnerable children grow to early adulthood without many avoidable problems. The organization sometimes works with other NGOs in some countries to help it achieve its goals. UNICEF through its conventions sets principles and guidelines for countries to follow in combating child prostitution. The organization then asks and helps countries to commit to their action plans in protecting children. They do this regionally or in individual countries. For example, UNICEFs second World Congress against Commercial Exploitation of Children set out guidelines and some countries made commitments to develop national plans of action against commercial sexual exploitation of children. A number of countries in the Eastern and Central African region made commitments to this strategy. These countries include Ethiopia, Kenya, Uganda, Madagascar, Mozambique, Seychelles, South A frica, Tanzania, Zambia, Zimbabwe, Namibia, Lesotho, Mauritius and Angola (UNICEF, 2001). Many of these countries face the problem of child prostitution both in the local countries and in foreign countries. Taking an example of Kenya, this country committed itself to the development of a national plan of action on commercial sexual exploitation of children (CSEC). Through this commitment, the country has formulated policies, programs and activities to help it to achieve the goal (UNICEF, 2001). This has made the country to engage NGOs in the fight against child molestation and sexual exploitation. The NGOs have involved children in the production of drama on child sexual abuse to raise awareness about this issue. The country has also formed the children department in one of its ministries to protect children. The new constitution of that country has comprehensively covered and clearly outlined the rights of children. The countrys government with the help of children rights groups has established strong regional co-operation with other countries. This is helping in checking child prostitution in foreign countries in this region and the world at large. In conclusion, child prostitution is a common problem in many countries of the world. In this practice, the children engage in sexual activity for monetary gain especially by the adults who either are their parents or their caretakers. Some children enter into prostitution due to the hard situations they face while others ere sold into sexual servitude by their parents either consciously or unconsciously. Child prostitution in foreign countries is also a common practice. People do this through sex tourism and child trafficking. Most people practice child prostitution in foreign countries either because they want to avoid the laws of their countries by breaking law in foreign countries or because they misunderstand the people of the countries that they visit. Child prostitution is a multi billion business in the world that leads to wastage of many childrens lives. In some countries, cultural practices contribute to the involvement of children in prostitution. Large and small criminal groups arrange for Trans boundary transfer of children and clients involved in child prostitution. Even though many human rights groups are against this immoral behavior, some governments have not fully committed themselves to eradicating this problem from their countries. Still there is much demand of foreign children for sex in some countries making the business of child trafficking and sex tourism to flourish. In whichever the case, children prostitution is a criminal offence and all people and especially governments need to fight to eradicate this problem from the society.

History And The Human Sciences As Systems Of Knowledge :: essays research papers

â€Å"What are the main difficulties human scientists confront when trying to provide explanations of human behaviour? What methods have been invented to circumvent these difficulties and to minimize their influence on the results that are obtained?† Although many people in the field of human sciences try to get their disciplines to be recognized as pure sciences, there are many differences that distinguish the natural sciences from the human sciences. There is a certain kudos that comes with the natural sciences that people in the human sciences crave, but human sciences can never be like the natural sciences. This is what causes there to be difficulties with human scientists trying to explain their science. They lack the definite, and factual ground on which the natural sciences are based. When a natural scientist hypothesises that when he heats some water to 100 degrees, it will boil. And then after an experiment, it is shown that it does, one can not argue that perhaps on another day the water wouldn’t feel like boiling at 100 degrees, or that perhaps it was only boiling at that temperature because there were people watching. Water boiling at 100 degrees is a scientific fact. It will occur every time the experiment is carried out. However, in the field of human sciences, these facts do not exist, and this makes it very difficult for a human scientist to prove any of his theories, or speculate on situations with any authority. The reason for this is that the study of human sciences involves, obviously, human behaviour. Human behaviour does not follow the same patterns that are obs erved with particles of matter, or certain metals, it is almost totally unpredictable. However, the human sciences do use similar methods of attaining knowledge to the natural sciences. The methods by which the human scientist attains knowledge has the same basic principles to that of the natural scientist. They have hypotheses which they test through observing, and analysing their observations. However, in the natural sciences, the observer is quite distinct from the experiment, as an astronomist is distinct from the planets and stars that he is observing. Whereas, in the human sciences, a human is the observer, and humans are the experiment. This complicates things. In every science there are theories. In the natural sciences these theories can be proved true or false, and therefore it can be determined whether these theories have an effect the result of the experiment.

The Business Model Essay -- Business Management Essays

The Business Model Michael Lewis (2000: pages 256-257) scoffed at the whole attempt to formalize the definition of business models when he wrote that â€Å" â€Å"Business Model† is one of those terms of art that were central to the Internet boom: it glorifies all manner of half baked plans. All it really meant was how you planned to make money.† In an abstract of his paper â€Å"A Mesoscopic Approach to Business Models: Nano Research on Management† published in â€Å"Economic Issues in China† Dr. Junyi Weng stated that â€Å"Business Model, a well known important and extensively used term by media, management consultancy and business top managers, is just in an embarrassment that there is no consensus about its definition and few papers in academic periodicals.† He designed and discusses his conception of business models based interfaces interacting in interior and exterior business environments. Peter Weill, Thomas W. Malone, Victoria T. D’Urso, George Herman and Stephanie Woerner of MIT in their paper â€Å"Do Some Business Models Perform Better than others?: A Study of the 1000 Largest US Firms† agree that the concept of business models is while widely discussed is seldom systematically discussed. The paper then proceeds to postulate a conceptual framework for comprehensively classifying business models. These consist of four basic types of business models (Creator, Landlord, Distributor and Broker), which are each broken down into four variants accordance with type of assets they deal in (physical, financial, intangible and human). Thus giving rise to 16 specialised business Model types.† Professor Michael Rappa like many others prefer to present a comprehensive and cogent taxonomy of basic categories as observed on the web as follows: Brokerage Advertising Infomediary Merchant Manufacturer (Direct) Affiliate Community Subscription Utility He however, does not believe that these are exhaustive and expects new and interesting variations in the future. KMLab Inc. offers an interesting definition: â€Å"a Business model is a description of how your company intends to create value in the market place. It includes that unique combination of products, services, image and distribution that your company carries forward. It also includes the underlying organization of people and the operational infrastructure that they use to accomplish their work. In some ways... ...rocesses such as inventory management etc. Maybelline a company founded in 1915 is one of the largest selling color cosmetics line in the United States. Its sells through outlets of almost every major mass-market retailer, such as supermarkets, drugstores, discount stores and cosmetics specialty stores. Its products are also available in over 70 countries worldwide. Maybelline uses a traditional model in its sales distribution network, which is the use of sales representatives to canvass for business and to arrange for sales. The use of sales representatives who are employees makes this a Business-to-Employee-to-Business interface model. In the 1990s the company a traditional â€Å"mortar† company re-invents itself a click and mortar company through the use of ICTs. However, one innovation to the sales representative concept is Maybelline’s use of its representatives as market intelligence reporters, who actually serve as the eyes of the company to monitor the progress of its products and the way they are handled by the retailers as well as progress of competitors’ products. This is the trading/sales structure of the company, which cannot be said to be a new business model.

The Need for Capital Punishment in America Essay examples -- Capital Pu

It is the firm belief and position here that committing such a crime as murder is punishable by death. Americans should take a position for anyone on death row, to be executed sooner rather than later. The moral reality in an argument for capital punishment is that they know the difference between the death penalty and what happens when it is actually put into place from the court of law. In the United States there are more people sitting in prison on death row than actually being executed at time of sentence. When the death penalty is not carried out, then families of the murdered victim recognize the value of the victim’s life is insignificant and the person that has committed the crime has the greater life of being able to continue living while in prison on death row. Many people argue for the death penalty with the case that is someone commits a violent crime, they should be put to death. Should anyone argue that if you take a human life, they will be able to live in prison and serve time and live, not to die by lethal injection or any of the other forms of capital punishment immediately? The argument for anyone in prison to not be punished and put to death is a crime w ithin itself. It is the belief of many that capital punishment is cruel and unjust. Although others would state the opposite to say that if you have committed murder, you to shall be put to death. In America anyone can have a right to believe that someone should live even if they have committed murder, especially if they have asked for forgiveness and all has been forgiven. Can it be justified that if anyone commits murder and then asked for forgiveness they be allowed to live and not be punished? Justice must be served here on earth as well as after deat... ... or disobeys God’s way in committing premeditated murder or involuntary manslaughter should be put to death immediately. Works Cited Adams, Cindy. â€Å"The Death Penalty as Just Punishment.† Does Capital Punishment Deter or is it a Biased Process? 3 Sept. 2008. 30 May 2010 . Andre, Claire, and Manuel Velasquez. â€Å"Capital Punishment.† Our Duty or Our Doom. 12 May 2010. 30 May 2010 . Colson, Charles W. â€Å"Capital Punishment.† The Rutherford Institute. 11 Nov. 2002. 30 May 2010 . Steiker, Carol S. â€Å"Capital Punishment and American Exceptionalism.† 2005. 30 May 2010 .

Basic Business Concepts

Business: It is the act of manufacturing, producing or buying and selling of goods and services whose aim is to make profit. A product may be defined as the output which could be in terms of services or goods within the normal business transaction.Generally, the fundamental goal of business if to make profit through optimization of its costs and revenue. However, business organizations are the entities that are ideally driven by the profit motive. Non profit making organizations does not aim atmaking profit. 2. Every business activity involves various participants/stakeholders.They include producers/manufactures, distributors, consumers and legal entities (John, 2006). Producers/manufacturers make the goods and services for use in the business process. Consumers are involved in using the products that are manufactured and produced in business processes. Distributors create channels of goods and service transfers from the manufactures to the consumers. Legal entities/government create s the legal layout of conduct between the other three participants. Studying business in the today’s American society is ideally an important aspect that provides information on the aspects that ensure strong business functionality.It provides the most rational knowledge that would help to succeed in any business process. However, business process is affected by various aspects such as international forces of demand and supply, income of the consumers, government regulation, availability of raw material, and economic systems (John, 2006). 3. Economics is the study of fundamentals of incorporating the scarce resources in processes that yield the highest benefit to the community. There are various economic systems which include; Traditional economy is that characterized by techniques and models based on social foundations.It involves resource inheritance and brings a passive sense of togetherness and community. It has low technology and no competition. Command economy is that w hich is controlled and planned by the central government. It is shaped by the will of the government. The means of economic production are owed by the people. It can be found in Vietnam. Market economy is controlled by forces of demand and supply. Government rarely fixes the prices. Private corporations govern the control of distribution and exchange. Example is United Kingdom.Mixed economy compliments both market and command economy. There are both the hands of government and corporations. It is governed by high freedom in its activities. An example is in US (John, 2006). 4. Supply is the total amount of goods and services offered in the market by the produces. Demand id the total quantity of goods and services required for consumption in the market. Price is the single cost paid for a unit of goods or services. Competition refers to the interactive process between suppliers and consumers within the market to yield an equilibrium quantity and price.In America, the competitive natur e of the market ensures the interaction between the quantities of goods and services supplied and demanded to produce an equilibrium price and quantity for the supplies and demands levels (John, 2006). 5. There are four types of competitions. Perfect competition is where we have many suppliers and consumers who interact cohesively with one another to yield an equilibrium quantity and price. Example is the hotel industry. Monopoly competition is where there is one supplier against many consumers. He/she controls the pricing of the goods and services.Example is the development in new communication technology. Duopoly competition is the competition between two suppliers. It may include the development in mobile phone technology between two manufactures. Oligopoly competition is where there are few sellers and many buyers. It may include the market of electronics. 6. The government uses various attributes to measure the state of economic development. They include; Inflation: This is the subsequent increase in the price of commodities. GDP: It is the sum total of all goods and services produced within a country within one year.Unemployment: It is the relationship between the workforce that is willing and also able to work and is in the process of finding a job compared to the number that is absorbed in the employment industry. Consumer Price Index: This is relative changes in the prices of consumer goods within the economy. The rate of unemployment is relative to the level of GDP. Higher unemployment implies lower GDP. This is because, there are low levels of income earned by the household and consequently law levels of aggregate demand within the economy. Economic fluctuations are usually desirable in the economic functionality theory.This is ideally because such fluctuations are detrimental in clearing the various markets within the economy. The federal government in America performs the role of ensuring both strong fiscal and monetary policies which ensure a str ong economy (John, 2006). 7. Service economy is the economy endowed with product output that is governed by services rather than goods. In America, service economy refers to the economic domains implied by the supply and demand of services as product outputs. Reference John Robert (2006) Economic Theory: An Introduction. New York, Prentice Hall

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