A thesis submitted to the faculty of humanities, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Doctor of philosophy Johannesburg, 26 May 2017 / The reality of South African education leaves little doubt that the school science textbook is the primary means by which the „what is taught and learnt‟ in science classrooms is determined. Reports from different countries suggest the same trait. The possibility that not all learners‟ „naïve ideas‟ originate in everyday life has also emerged in the literature along with allusions to the quality of textbooks. If school textbooks are to be blamed, even partially, for learners‟ naïve ideas, a systematic analysis of their subject content becomes requisite. The present study is a systematic content analysis of presentations of foundational aspects of Electrostatics, in approved South African physical sciences textbooks in use after the first democratic elections of 1994, thus representing and addressing three curricula school education has gone through since. The study was perceived as a first step to an anticipated analysis of the entire topic Electromagnetism to which Electrostatics is part of, given its difficulty as has been widely reported in the literature and its status in school curricula. Using the conceptual framework of the Classical Electromagnetic Theory, six foundational aspects of Electrostatics were demarcated for the analysis, targeting the concept charge, its origins, transfer and conservation, the distinction between conductors and insulators, the attraction between charged and uncharged objects, as well as global perceptions of Electrostatics and its place within Electromagnetism. Categorisation tables with theoretically grounded indicators were developed as the primary constructs against which texts were analysed, but inductive categorisation tables emerged from the texts as well. An additional construct was necessitated and developed, the “Organisation of the science educator‟s thought”, based on the notion of a scientific explanation and the nature of scientific models, for analysing links between macro and micro. The analysis revealed that the subject matter content of Electrostatics in South African textbooks is of major concern, giving learners no reason to make sense or develop an appreciation for science, physics in particular. In fact it is not science. The analysis suggests that the long lists of problems revealed, have their origin in two main drawbacks: Firstly, inadequate author understanding of the concept charge, disregarded or misused in the texts, and secondly, author unawareness of the inferred nature of science models, affecting purpose of accounts, explanations and reasoning. Furthermore, certain unprofessional author practices are suggested, such as lack of familiarity with curricula and the content of other topics (not a single link was found), lack of research, and general disregard for learners‟ difficulties, while misconceptions identified in the literature are all communicated in the texts, most explicitly so. The findings suggest that science textbook authors are in need of training. / MT2017

The research presented in this thesis is situated within an interpretivist paradigm. Within this paradigm, a qualitative case-study research approach was adopted. This seemed most appropriate in my research project since the main focus is on elicitation of prior knowledge and incorporation of such knowledge into 'hands-on' and 'minds-on' practical activities with a view to improving conceptual development. For the purposes of this research project, I designed an interactive teaching and learning unit in electrostatics as an attempt to put into practice a learner-centred approach. This approach, in my view, is in line with the new curriculum in South Africa. The emerging central theme of this thesis is the notion of active participation by learners during teaching and learning. This study was carried out over a period of two years and involved my grade 9 learners, who participated voluntarily. The research process documented in this thesis has been conceptualised into two phases. Phase one was concerned with the elicitation of learners' prior knowledge around lightning. In phase two, learners were engaged in 'hands-on' and 'minds-on' practical activities, and key concepts were identified to ensure conceptual development. The data was collected using a variety of data collection tools, namely: focus group interviews, follow-up whole-class semi-structured interviews, worksheets, videotaped lessons and photographs. The analysis of data revealed that learners come to class with prior knowledge concerning lightning. Within this prior knowledge it was found that there were both ‘scientific’ and ‘non-scientific’ concepts. The identification of key concepts during practical activities was found to be very useful in promoting learning. However, the incorporation of prior knowledge into practical activities posed a challenge and needs further research. iv This research study also highlights some insights into some of the complexities of elicitation and incorporation of learners' prior knowledge, and conceptual development in science classrooms. It also demonstrates the challenges and possibilities during teaching and learning as well as the realities of the demands of the new curriculum and OBE in South Africa, in particular, in historically disadvantaged schools

Lightning as a natural phenomenon is shallowly presented in the Namibian curriculum documents such as the syllabus and textbooks. This gap in curriculum triggered my interest to investigate whether learners’ meaning-making in static electricity was enabled or constrained by elicitation and integration of their cultural beliefs and experiences about lightning and by their practical activities. This study was conducted with my grade 8 learners at the school where I am currently teaching. The school is located in a rural area in Ohangwena region in Northern Namibia. The study is situated within an interpretive paradigm. Within the interpretive paradigm, a qualitative case study approach was adopted. I considered this methodological orientation appropriate in this study as it allowed me to use the following data gathering methods: document analysis, brainstorming, discussions and presentations, semi-structured interview, focus group interview, observation and an assessment test. Multiple methods to gather data were used for triangulation and validation purposes. For data analysis purposes, the data sets were colour-coded to derive themes and analytical statements. Ethical considerations were also taken seriously in this study and all participants gave consent. An analysis of data revealed that there is no learning objective or basic competence in the Namibian Physical Science syllabus for grade 8-10 that requires learners to bring in their cultural beliefs and experiences, in particular, about lightning. Yet the study revealed that learners possess a lot of prior everyday scientific and non-scientific knowledge and experiences about lightning that they had acquired from their communities. Also, mobilization of learners' everyday knowledge and experiences about lightning enabled learner engagement during the science lessons. Likewise, engaging learners in practical activities in static electricity helped them to make meaning of scientific concepts. Based on my research findings, I therefore, recommend that learners' prior everyday knowledge and experiences about lightning should be incorporated during teaching and learning of the topic on static electricity.

Orientador: Cesar José Bonjuani Pagan / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-20T02:16:17Z (GMT). No. of bitstreams: 1 TrindadedeOliveira_Murilo_M.pdf: 8021703 bytes, checksum: 3faa29c4fb8fec84d66f98a7389ed1b5 (MD5) Previous issue date: 2012 / Resumo: Nesta dissertação propomos a análise de uma idealização estabelecida dentro da teoria eletromagnética. A partir de Um Tratado sobre Eletricidade e Magnetismo, James C. Maxwell expõe alguns conceitos físicos relativos ao aterramento elétrico em condutores. Assim, ele estima que a presença de um fio condutor que estabelece a conexão entre um corpo condutor e outro, ou mesmo ao terra elétrico, perturba as características do sistema envolvido (carga, potencial e campo elétrico). Desse modo, Maxwell preconiza que para sistemas teóricos ou idealizados, quão indefinidamente fino seja o fio, indefinidamente menor será a perturbação gerada. A contextualização de uma idealização física dentro do ensino da teoria eletromagnética, especialmente para um curso de engenharia, é necessária no intuito de enfatizar as diferenças entre modelos reais e teóricos, uma vez também que os estudantes destes cursos devem estar interessados no desenvolvimento prático dos conceitos apreendidos em sala de aula. Nesse sentido, quando tratamos do método das imagens, especificamente para o problema de uma carga na presença de um condutor esférico aterrado, temos a oportunidade de explorar os limites de um modelo teórico, delimitando quais nuances podem aproximá-lo de uma aplicação no mundo real. Em vista disso, notamos que a maioria dos livros didáticos usados no ensino do eletromagnetismo, quando lidam com o problema do aterramento da esfera, simplesmente negligenciam a questão suscitada por Maxwell, de modo a transformar o problema em um exercício puramente matemático, sem necessidade de explicar os fundamentos físicos que sustentam a solução do problema. Portanto, o intuito do presente trabalho é desenvolver um modelo cuja solução defina o comportamento físico para ambos os casos (levando em consideração ou não a existência da conexão da esfera com o terra elétrico), bem como verificar os limites deste modelo teórico / Abstract: In this work, we propose the analysis about an idealized established within electromagnetic theory. From A Treatise on Electricity and Magnetism, James C. Maxwell presents some physical concepts related to electrical conductors grounded. In this direction, he estimates that the presence of a straight metallic wire which establishes the connection between a conducting body and another, or even to electrical ground, disturbs the properties of the system involved (charge, potential and electric field). Thus, Maxwell preconize for theoretical or idealized systems, how indefinitely thin is the wire, indefinitely lower is the disturbance created. The context of a physical idealization into the teaching of electromagnetic theory, especially for an engineering degree is required in order to emphasize the differences between real and theoretical models, since the students of these courses should be also interested in the practical development of the concepts learned in the classroom. In this sense, when we discussed the method of images, specifically to the problem of a charge point charge in the presence of a grounded conducting sphere, we have the opportunity to explore the limits of a theoretical model, outlining which nuances can approach it to a real world application. In view of this, we note that most of the textbooks used in teaching electromagnetism, when deals with the problem of grounded sphere, they simply neglect the issue raised by Maxwell. In order to transform the problem into a purely mathematical exercise, without to explain the physical foundations that support the solution of the problem. Therefore, the aim of this work is to develop a model whose solution defines the physical behavior for both cases (taking into account or not the existence of a connection of the sphere with the electrical ground), and to verify the limits of this theoretical model / Mestrado / Eletrônica, Microeletrônica e Optoeletrônica / Mestre em Engenharia Elétrica