Photoelectric Effect and Einsteins 1921 Nobel Prize

The photoelectric effect posed a significant challenge to the study of optics in the latter portion of the 1800s. It challenged the classical wave theory of light, which was the prevailing theory of the time. It was the solution to this physics dilemma that catapulted Einstein into prominence in the physics community, ultimately earning him the 1921 Nobel Prize. What Is the Photoelectric Effect? Annalen der Physik When a light source (or, more generally, electromagnetic radiation) is incident upon a metallic surface, the surface can emit electrons. Electrons emitted in this fashion are called photoelectrons (although they are still just electrons). This is depicted in the image to the right. Setting Up the Photoelectric Effect By administering a negative voltage potential (the black box in the picture) to the collector, it takes more energy for the electrons to complete the journey and initiate the current. The point at which no electrons make it to the collector is called the stopping potential Vs, and can be used to determine the maximum kinetic energy Kmax of the electrons (which have electronic charge e) by using the following equation: Kmax eVs The Classical Wave Explanation Iwork function phiPhi Three main predictions come from this classical explanation: The intensity of the radiation should have a proportional relationship with the resulting maximum kinetic energy.The photoelectric effect should occur for any light, regardless of frequency or wavelength.There should be a delay on the order of seconds between the radiation’s contact with the metal and the initial release of photoelectrons. The Experimental Result The intensity of the light source had no effect on the maximum kinetic energy of the photoelectrons.Below a certain frequency, the photoelectric effect does not occur at all.There is no significant delay (less than 10-9 s) between the light source activation and the emission of the first photoelectrons. As you can tell, these three results are the exact opposite of the wave theory predictions. Not only that, but they are all three completely counter-intuitive. Why would low-frequency light not trigger the photoelectric effect, since it still carries energy? How do the photoelectrons release so quickly? And, perhaps most curiously, why does adding more intensity not result in more energetic electron releases? Why does the wave theory fail so utterly in this case when it works so well in so many other situation Einstein's Wonderful Year Albert Einstein Annalen der Physik Building on Max Plancks blackbody radiation theory, Einstein proposed that radiation energy is not continuously distributed over the wavefront, but is instead localized in small bundles (later called photons). The photons energy would be associated with its frequency (ÃŽ ½), through a proportionality constant known as Plancks constant (h), or alternately, using the wavelength (ÃŽ ») and the speed of light (c): E hÃŽ ½ hc / ÃŽ » or the momentum equation: p h / ÃŽ » ÃŽ ½Ãâ€  If, however, there is excess energy, beyond φ, in the photon, the excess energy is converted into the kinetic energy of the electron: Kmax hÃŽ ½ - φ The maximum kinetic energy results when the least-tightly-bound electrons break free, but what about the most-tightly-bound ones; The ones in which there is just enough energy in the photon to knock it loose, but the kinetic energy that results in zero? Setting Kmax equal to zero for this cutoff frequency (ÃŽ ½c), we get: ÃŽ ½c φ / h or the cutoff wavelength: ÃŽ »c hc / φ After Einstein Most significantly, the photoelectric effect, and the photon theory it inspired, crushed the classical wave theory of light. Though no one could deny that light behaved as a wave, after Einsteins first paper, it was undeniable that it was also a particle.

The Impact of the Documents of the Protestant Reformation

The Impact of the Documents of the Protestant Reformation The documents of the Protestant Reformation offer a tremendous amount of significance for World History as they were symbols of tremendously revolutionary events. Their impact was widespread and across continents for many years, resulting in a reevaluation of monarchies, spirituality and ones relationship with the divine. Context The documents of the Reformation pushed people into a situation where they had to make a definitive decision regarding their personal religion, whether they were going to be Catholic or Protestant. While today such a decision might seem purely personal and private, such a decision in the 1500s in many ways could be a matter of life and death, given the intense religious wars in that time period (Kreis, 2009). The reformation took place during the 16th century as a manifestation of widespread dissatisfaction with the Church which occurred at all levels of European society (Kreis, 2009). Many Christians were on a journey seeking personal salvation and generally didnt find the Churchs focus on rituals terribly conducive to such a goal; this time marked a decided shift from the salvation of entire groups of people to something more intimate and individual (Kreis, 2009). The sacraments had become forms of ritualized behavior that no longer spoke to the people of Europe. They had become d evoid of meaning. And since more people were congregating in towns and cities, they could observeShow MoreRelatedThe Invention Of The Printing Press932 Words   |  4 Pagestwo effects were the exploration of the Americas and the Protestant Reformation. Exploration was Colombus and his explorers â€Å"discovering† America. The printing press had great influence on these events. The Protestant Reformation was also shaped by the printing press, in some cases more than exploration. The Protestant Reformation, or more simply, The Reformation, was a mass conversion of people from the Catholic Church to the Protestant Church. The citizens of Europe started to access more informationRead MoreThe Protestant Reformation And The Reformation916 Words   |  4 PagesThe Protestant Reformation took place in the 16th century and was a major European movement whose goal was to reform the beliefs and practices of the Roman Catholic Church. This movement led to people worshipping God as th ey wanted and no longer relying on the Catholic Church for guidance with religious matters. Even though people were doing what they believed, the Protestant Reformation brought many conflicts. Religious disagreements caused bloody conflicts all over Europe. The principal figureRead MoreThe Legacy of Edward VI as Explained in Tudor Church Militant: Edward VI and the Protestant Reformation923 Words   |  4 Pagesand the Protestant Reformation. London, Penguin Books, 2001. 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Martin Luther was responsibleRead MoreMartin Luther And The Protestant Reformation1326 Words   |  6 Pagespower. Thus the Religious Reformation period was the most important time because new religions were formed and the RCC had all the power. Indeed supporters of the Reformation Religions believe that this time had the biggest impact because during this time new religions were created and millions changed faith. In his text â€Å"Martin Luther† the author argues that â€Å"Martin Luther as a Christian theologist and Augustinian monk whose teachings inspired the Protestant Reformation†. Martin Luther was theRead MoreFive Solae Essay1392 Words   |  6 Pageslifestyle, based on private prayer, worship, study, and individual ethical choice. This was difficult for many to do.† Not only was the Protestant Reformation a crucial time in the history of Europe, but also in the history of the entire world. The Protestant Reformation marked a massive alteration of religion. New religious ideas flourished during the Reformation, thus, challenging the beliefs of the Roman Catholic Church. A storm of question began to emerge against the Roman Catholic Church becauseRead MoreDifferent Impacts on Religion1067 Words   |  5 PagesLuther’s Address to the Christian Nobility of the German Nation had an immense impact on religion. Martin Luther’s document would pave the way for the Protestant Reformation, while Louis XIV would revoke all the freedoms that the Huguenots enjoyed in a Catholic France with the Edict of Nantes. This essay will compare and contrast these distinctions and their impact on religion. Therefore, although years apart, these two documents lead a paradigm shift, address what they believe to be â€Å"evils† plaguing theirRead MoreDBQ: Causes of the Protestant Reformation739 Words   |  3 PagesThere are approximately eight hundred million Protestant Christians currently in the world with it being the second largest Christian domination (Fairchild). However, there are over a billion followers of the Roman Catholic faith and it curre ntly stands as the Christian domination with the most followers (Fairchild). If it were not for the German monk, Martin Luther, most Christians would have been Roman Catholic in the present. Martin Luther is famous for â€Å"95 Theses† that critiqued the practicesRead MoreThe German Reformer Martin Luther930 Words   |  4 Pages The German reformer Martin Luther was the first and greatest figure in the sixteenth-century Reformation. An author of commentaries on Scripture , theology, and priestly abuses, a hymnologist (writer of hymns [sacred songs]), and a preacher, from his own time to the present he has been a symbol of Protestantism (group of Christian faiths that do not believe in the supremacy of the pope, but in the absolute authority of the Bible). Luther had an intriguing childhood with his father, a majorRead MoreThe Religious Conscience Of Europe1178 Words   |  5 Pagespersonal faith, and minister to the needs of others. Communication resources have bec ome the glue that holds together nations, corporations, faith communities and families. This has not always been true, the many events of the sixteenth century Reformation vastly influenced the development of Christianity. As the fifteenth century closed, it was clear that the church was struggling and in need of reform. Corruption of the papacy was widespread and distrust filled the minds of the people. Historian

The Issue Of Same Sex Marriage - 1404 Words

The issue of same-sex marriage in America right now is convoluted since the political culture of each state varies. Marrying the person you love can be either effortless or unbelievably difficult— sometimes even illegal. Although it wasn’t openly spoken about, homosexuality was frowned upon in the United States. Some companies refused to hire people if they knew they were gay. Baker v. Nelson was one of the first court cases in which the legal system was challenged on the topic of same-sex marriage. The conflict originally took place in Minneapolis when Richard John Jack Baker and James Michael McConnell attempted to obtain a marriage license from Gerald Nelson, the Hennepin County District Court clerk. He denied their application because†¦show more content†¦They declared â€Å"only a marriage between a man and a woman is valid in this state† (Schulin, 2010). Those who are not given the rights to marry a person of the same-sex have important benefits wi thheld that come along with marriage. This is precisely what happened to Karen Thompson from Minnesota; her partner, Sharon Kowalski, was in a car accident in 1983 that left her brain damaged and quadriplegic. Thompson had to file appeals in local, state and federal courts in order for her to be able to legally take care of Kowalski. Kowalski’s parents, Donald and Della, opposed of their partnership and put her in a nursing home in 1985 with no visiting rights for Thompson. In 1991, she subsequently became the legal guardian for Kowalski. The director of the American Civil Liberties Union’s Lesbian and Gay Rights Project, William Rubenstein, said it best: â€Å"...It took her seven years to do so, when guardianship rights for a heterosexual married couple would be taken for granted† (Lewin, 1991). The federal government’s delegated powers do not include the regulation of marriage in the states in accordance to the U.S. Constitution. However, President Bil l Clinton signed the Defense of Marriage Act into law in 1996. Section 3 of this federal law characterized marriage as the joining of only a woman and a man. It allowed states to deny the recognition of same-sex marriages that have been authorized in other states while only acknowledging the marriages of

Recruitment & Selection Policies - Solution of Analysis Report

Question: Analyse the recruitment and selection policies of chosen organization, to show how they attempt to maintain and improve their positions in the sector in which they operate. The organization chosen is Harrods London. Answer: Introduction: All over the world, Harrods is a recognizing brand. It has the 330 different departments all over the world. Its brand values are the biggest asset for the company. The organization mainly stands for its brand values. Innovation, sensation, luxury, service are the values of the Harrods. Fig 1: values of Harrods The recruitment and selection process of Harrods should be unique so that they can increase their profitability with the vital resources of the organization. The public faces of the company are the employees of the organization. To ensure the day-to-day running of the business, they have to interact with their employees, customers, managers, stakeholders etc. In 2010 from Mohamed Al-Fayed Qatar holding purchased Harrods. To the continuing success of the business, they recognize the engaged employees in the organization. In the recruitment and selection process, the main role to manage employee relationship in the organization is human resource department. There are different recruitment policies and procedures of every company. Therefore, Harrods has the different recruitment policies and procedures to increase the employee engagement in the company (Abou-Moghli, 2015). The recruitment and selection polices are following: The policy of conduct scrutinize by the organization only. From the time, the recruitment date to open the job vacancy to the position fills, it happens in chronological order. The suitable candidate for the organization that has the specific skills and knowledge for the open position in the organization has to be identifying by the human resource department of the company. The company should give the best opinion about every candidate so that they can choose the right candidate from the whole lot. All applicable employment laws to the candidates those are selected by the company. It means the company is giving the equal opportunity to every candidate (Fabel and Pascalau, 2013). Essential principles: The recruitment polices and the selection procedure is based on the underlying principles that are following: Based on sustainability with respect to the position, the applicant will be chosen by the company. The company to all the applicants should inform the details of the vacant position and the application procedures. The company should provide the necessary information to the candidate so that they can have a clear idea about the job description. The company should see if the candidate is suitable for the position or not. The company should not be disclosing the candidates information with others; they should respect their privacy and should be treating with confidentiality with the candidate information. If any employees of the organization are submitting any complaint in written to the company, then it is the responsibility of the company to give response of the compliant in writing (Ghazala Ishrat, 2013). A vacancy within the company and the recruitment candidates takes place the policies are applies to a procedure that is conducts by: a) Notice board or internal recruitment b) Advertisements through newspaper, online media or public announcements by the company c) Executive search Position information: If the company wants to fill a vacancy for a particular position then the company decides the vacancy should be filling or can be hold or not. The specific job detail will need the specific candidates who are suitable for the position or not. The job description should clearly mentioned by the company to the candidates. The company to the candidates should clarify the specific duties and the responsibilities of the particular position so that they can have the clear idea about the position (Thibault et al., 2015). The employment status or the nature of the employment should clarify by the company to the candidates that the job is for permanent basis or for temporary basis. The employee need to work in the shift or should be working at a specific hours. The company that is skills and knowledge, experience about the particular job should consider the professional proficiency of the job description. The company should give a detail idea to all the employees in the organization about the job description of a particular job (Machado and Davim, 2014). Recruitment: The job advertisement will state the method of application, in relevant to the job description. Selection phase: The company should give the proper details to the candidate that at what time the employee should join in the organization. If the company found the right candidate for the specific job description, then the vacancy should be close at a proper time. Some more conditions that need to consider by the company are following: a) When the vacancies of the company fully closed, the rejected application needs to be considering by them (Mahmood, 2014). b) The interview of the candidate schedule needs to be invited by the company. The company should inquire the same questions for the related job or position to the candidate so that the company can know about the candidates knowledge, experience, and their educational background so that the company can know about them very clearly. The company should inform the candidates about the detail job vacancy and the information about the complete order of the job description so that the employee has the detail idea about the job specification (Miles and Sadler-Smith, 2014). Further information: If the employees need the further information about the job description or the duties and the responsibilities of the specific job then the company should take the responsibilities to give a detail about the job description to the employees of the organization. Rejection and completion of the application procedure: In the process of selection and recruitment procedure, if the company has realized that the many candidates did not fulfill the criteria for a specific job then the company should give a message by email or in written process so that the candidate have a clear proof of the process. There will be a situation when the candidate fulfills all the criteria but the job vacancy for some particular position has already filled then the company can retain those candidatess resume in their database for further clarification (Neumann, 2013). Conclusion: After considering the above discussion, the company Harrods is using these policies for recruiting and selecting the right candidate for their organization to increase the profitability and the quality of standard. References Abou-Moghli, A. (2015). Recruitment and Selection and Their Effect in Achieving the Institutional Excellence.International Business Research, 8(3). Fabel, O. and Pascalau, R. (2013). Recruitment of Seemingly Overeducated Personnel: InsiderOutsider Effects on Fair Employee Selection Practices.International Journal of the Economics of Business, 20(1), pp.57-82. Ghazala Ishrat, G. (2013). A comparative study of Recruitment Selection, Training and Development policies in Indian MNCs and Foreign MNCs.IOSR Journal of Business and Management, 7(5), pp.29-43. Machado, C. and Davim, J. (2014).Work Organization and Human Resource Management. Dordrecht: Springer. Mahmood, M. (2014). Strategy, structure, and HRM policy orientation: Employee recruitment and selection practices in multinational subsidiaries.Asia Pacific Journal of Human Resources, 53(3), pp.331-350. Miles, A. and Sadler-Smith, E. (2014). With recruitment I always feel I need to listen to my gut: the role of intuition in employee selection.Personnel Review, 43(4), pp.606-627. Neumann, G. (2013). Recruitment policies.The Physics Teacher, 25(2), p.72. Thibault, E., Lynch, L., McBride, R. and Walsh, G. (2015).Proactive police management. Boston: Pearson.