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ABSTRACT The aim of this study was to investigate the effect of an active learning approach (ALA) on the achievement of 11 th grade learners in Newton’s laws of motion, The case study was done in one school by comparing the achievement of learners in Newton’s laws of motion through an Active Learning Approach (ALA) with that of learners taught through Traditional Direct I nstruction (TDI) and to determine whether learners taught with ALA retained the material better than those taught with TDI. Two grade 11 classes in one school in the Queenstown District of the Eastern Cape were selected on their performance in two differen t tests and used as case study . The Force Concept Inventory was used to determine the achievements and retention of knowledge of the two groups. The effect of the active lear ning approach on the treatment group was also measured by ask ing each learner in t he group to complete a learner assessment of instruction form. The treatment group was also subjected to a classroom group interview. T he following information emerged from the study: i) Learners taught using the ALA achieved significantly better in FCI pos t - test than those taught with traditional direct instruction. ii) In the retention of knowledge test, the mean score of the learners taught using the ALA was 4.8% higher than those taught with TDI although insignificant. iii) Learners subjected to the ALA liked the instructional approach and as such put in extra time to learn. The findings suggest that the active learning approach had positive effect on the achievement of the Grade 11 learners and thus, can be adapted to enhance learning in the classroom. / Physics

O objetivo deste trabalho é investigar o desenvolvimento da mecânica racional newtoniana, particularmente acompanhar sua inauguração com os Philosophiae Naturalis Principia Mathematica e a subseqüente recepção do programa pela filosofia continental, no século XVIII, por alguns intelectuais e cientistas. Utiliza-se a metodologia dos programas de pesquisa científica como referencial epistemológico na caracterização e descrição do programa, e também a abordagem historiográfica que ela implica. Epistemologicamente, procura-se escrutinar e precisar o sentido da noção de núcleo duro, em particular sua aplicação ao programa newtoniano de mecânica racional, mediante a análise detida do que Lakatos concebeu como o núcleo duro do mencionado programa, as leis dinâmicas e da gravitação apresentadas nos livros I e III dos Principia. O núcleo do programa da mecânica racional newtoniana é pensado por Newton como axiomas ou leis do movimento (Axiomata sive leges motus). Essa caracterização das hipóteses fundamentais da mecânica newtoniana aponta para sua centralidade, o que aparentemente confirma a idéia fundamental de Lakatos de que um programa de pesquisa é caracterizado pelo seu núcleo duro. A questão que motiva este ensaio pode ser formulada nos seguintes termos: dado que, segundo Lakatos, o núcleo duro é o componente conceitual (caracterizado metodologicamente) que define os contornos da prática científica em determinado campo, primeiro, não seria o núcleo duro estruturado através da correlação com outros componentes da teoria de racionalidade de Lakatos, em particular da heurística positiva? Segundo, as suposições compartilhadas pelos partidários de um programa de pesquisa possuirão alguma característica distintiva (epistemológica) que legitime sua proteção em relação à refutação? Por fim, aplicada à história da ciência, esta noção metodológica resiste a um escrutínio historiográfico? / The aim of this paper was to investigate the development of Newtonian rational mechanics, in special to analyze our rise with the publication of Philosophiae Naturalis Principia Mathematica and the consequent program reception by the continental philosophy. Was used the methodology of scientific research programs like epistemological framework in the programs characterization and description, and too the historiography approach entangled by it. Epistemologically the aim is to scrutiny and to particularize the notion of hard core, specially in your application to Newtonian rational mechanics program, through the analyze of Lakatos conception of referred programs hard core: the dynamics laws of motion and the law of gravitation , presented in books I and III of Principia. To summarize, the question which motive this paper can be formulated in the following way: accepted the supposition that the hard core is the conceptual component which define the demarcation of the scientific practice in a established scope stability, first, the hard core will be not reducible to the others components of Lakatos´ theory of scientific rationality, like a face of positive heuristics? Second, will have the shared suppositions in a scientific program any distinctive characters (epistemological) which legitimate the protection of them face the refutation? At last, applied to the History of Science, this epistemological notion resist against a historic scrutiny?

O objetivo deste trabalho é investigar o desenvolvimento da mecânica racional newtoniana, particularmente acompanhar sua inauguração com os Philosophiae Naturalis Principia Mathematica e a subseqüente recepção do programa pela filosofia continental, no século XVIII, por alguns intelectuais e cientistas. Utiliza-se a metodologia dos programas de pesquisa científica como referencial epistemológico na caracterização e descrição do programa, e também a abordagem historiográfica que ela implica. Epistemologicamente, procura-se escrutinar e precisar o sentido da noção de núcleo duro, em particular sua aplicação ao programa newtoniano de mecânica racional, mediante a análise detida do que Lakatos concebeu como o núcleo duro do mencionado programa, as leis dinâmicas e da gravitação apresentadas nos livros I e III dos Principia. O núcleo do programa da mecânica racional newtoniana é pensado por Newton como axiomas ou leis do movimento (Axiomata sive leges motus). Essa caracterização das hipóteses fundamentais da mecânica newtoniana aponta para sua centralidade, o que aparentemente confirma a idéia fundamental de Lakatos de que um programa de pesquisa é caracterizado pelo seu núcleo duro. A questão que motiva este ensaio pode ser formulada nos seguintes termos: dado que, segundo Lakatos, o núcleo duro é o componente conceitual (caracterizado metodologicamente) que define os contornos da prática científica em determinado campo, primeiro, não seria o núcleo duro estruturado através da correlação com outros componentes da teoria de racionalidade de Lakatos, em particular da heurística positiva? Segundo, as suposições compartilhadas pelos partidários de um programa de pesquisa possuirão alguma característica distintiva (epistemológica) que legitime sua proteção em relação à refutação? Por fim, aplicada à história da ciência, esta noção metodológica resiste a um escrutínio historiográfico? / The aim of this paper was to investigate the development of Newtonian rational mechanics, in special to analyze our rise with the publication of Philosophiae Naturalis Principia Mathematica and the consequent program reception by the continental philosophy. Was used the methodology of scientific research programs like epistemological framework in the programs characterization and description, and too the historiography approach entangled by it. Epistemologically the aim is to scrutiny and to particularize the notion of hard core, specially in your application to Newtonian rational mechanics program, through the analyze of Lakatos conception of referred programs hard core: the dynamics laws of motion and the law of gravitation , presented in books I and III of Principia. To summarize, the question which motive this paper can be formulated in the following way: accepted the supposition that the hard core is the conceptual component which define the demarcation of the scientific practice in a established scope stability, first, the hard core will be not reducible to the others components of Lakatos´ theory of scientific rationality, like a face of positive heuristics? Second, will have the shared suppositions in a scientific program any distinctive characters (epistemological) which legitimate the protection of them face the refutation? At last, applied to the History of Science, this epistemological notion resist against a historic scrutiny?

Este trabalho teve como objetivo a elaboração de uma sequência didática em nível de Ensino Médio sobre Leis de Newton, para ser utilizada com o método de ensino Peer Instruction. (Instrução pelos Colegas). Esta sequência didática foi aplicada em quatro turmas (totalizando 118 alunos) da primeira série do Ensino Médio Técnico de uma escola pública de Novo Hamburgo – RS. A concepção de todo o material elaborado foi alicerçada na Teoria da Aprendizagem Significativa de David Paul Ausubel. As aulas foram estruturadas em sete encontros de uma hora e quarenta minutos cada um, sendo que em seis deles foi empregado o método Peer Instruction para a aprendizagem conceitual do conteúdo, intercalando-se questões envolvendo cálculos e o último encontro foi destinado à avaliação de todas as etapas do processo. A análise dos dados revela que as turmas obtiveram ganhos significativos de aprendizagem. Observou-se que as discussões entre os colegas foram proveitosas, propiciando a participação dos alunos como protagonistas do seu próprio processo de ensino-aprendizagem e levaram a um aumento do percentual de acertos das questões conceituais propostas. O retorno dado pelos alunos demonstra que a dinâmica da aula os motiva a trabalhar e os mantêm envolvidos com o trabalho por mais tempo. Conclui-se que esta sistemática pode se estender a outros conteúdos da Física, aumentando a interação entre os alunos e a reflexão crítica sobre os fenômenos que estão sendo abordados. Para a aplicação desta proposta foram elaboradas: tarefas prévias, os momentos da sequência didática e um banco de questões conceituais. / This work aimed to develop a high school level didactical sequence about Newton’s Laws of motion, suitable for use with Peer Instruction teaching method. This didactical sequence was implemented in four first grade classes (totaling 118 students) of a public technical High School in Novo Hamburgo (Brazil). The conception of all material was based on David Paul Ausubel’s Meaningful Learning Theory. The classes were organized in seven meetings of one hour and forty minutes each. The Peer Instruction method was used for conceptual learning during six of these meetings, interspersing questions involving calculations. The last meeting was dedicated to evaluate all the stages of the process. The performance analysis of the data reveals that the students obtained significant learning gains. The discussions among the students were useful, allowing the participation of students as protagonists of their own teaching-learning process and led to an increase in the percentage of correct answers to the proposed conceptual questions. The feedback given by the students demonstrates that the dynamics of the class motivates them to work and keeps them involved with the work. We can conclude that this systematics can be extended to other contents of Physics, stimulating the interaction between the students and the reflection on the phenomena that are being approached. For the application of this proposal were elaborated: previous tasks, a didactical sequence in moments and a bank of conceptual questions.

Este trabalho teve como objetivo a elaboração de uma sequência didática em nível de Ensino Médio sobre Leis de Newton, para ser utilizada com o método de ensino Peer Instruction. (Instrução pelos Colegas). Esta sequência didática foi aplicada em quatro turmas (totalizando 118 alunos) da primeira série do Ensino Médio Técnico de uma escola pública de Novo Hamburgo – RS. A concepção de todo o material elaborado foi alicerçada na Teoria da Aprendizagem Significativa de David Paul Ausubel. As aulas foram estruturadas em sete encontros de uma hora e quarenta minutos cada um, sendo que em seis deles foi empregado o método Peer Instruction para a aprendizagem conceitual do conteúdo, intercalando-se questões envolvendo cálculos e o último encontro foi destinado à avaliação de todas as etapas do processo. A análise dos dados revela que as turmas obtiveram ganhos significativos de aprendizagem. Observou-se que as discussões entre os colegas foram proveitosas, propiciando a participação dos alunos como protagonistas do seu próprio processo de ensino-aprendizagem e levaram a um aumento do percentual de acertos das questões conceituais propostas. O retorno dado pelos alunos demonstra que a dinâmica da aula os motiva a trabalhar e os mantêm envolvidos com o trabalho por mais tempo. Conclui-se que esta sistemática pode se estender a outros conteúdos da Física, aumentando a interação entre os alunos e a reflexão crítica sobre os fenômenos que estão sendo abordados. Para a aplicação desta proposta foram elaboradas: tarefas prévias, os momentos da sequência didática e um banco de questões conceituais. / This work aimed to develop a high school level didactical sequence about Newton’s Laws of motion, suitable for use with Peer Instruction teaching method. This didactical sequence was implemented in four first grade classes (totaling 118 students) of a public technical High School in Novo Hamburgo (Brazil). The conception of all material was based on David Paul Ausubel’s Meaningful Learning Theory. The classes were organized in seven meetings of one hour and forty minutes each. The Peer Instruction method was used for conceptual learning during six of these meetings, interspersing questions involving calculations. The last meeting was dedicated to evaluate all the stages of the process. The performance analysis of the data reveals that the students obtained significant learning gains. The discussions among the students were useful, allowing the participation of students as protagonists of their own teaching-learning process and led to an increase in the percentage of correct answers to the proposed conceptual questions. The feedback given by the students demonstrates that the dynamics of the class motivates them to work and keeps them involved with the work. We can conclude that this systematics can be extended to other contents of Physics, stimulating the interaction between the students and the reflection on the phenomena that are being approached. For the application of this proposal were elaborated: previous tasks, a didactical sequence in moments and a bank of conceptual questions.

Este trabalho teve como objetivo a elaboração de uma sequência didática em nível de Ensino Médio sobre Leis de Newton, para ser utilizada com o método de ensino Peer Instruction. (Instrução pelos Colegas). Esta sequência didática foi aplicada em quatro turmas (totalizando 118 alunos) da primeira série do Ensino Médio Técnico de uma escola pública de Novo Hamburgo – RS. A concepção de todo o material elaborado foi alicerçada na Teoria da Aprendizagem Significativa de David Paul Ausubel. As aulas foram estruturadas em sete encontros de uma hora e quarenta minutos cada um, sendo que em seis deles foi empregado o método Peer Instruction para a aprendizagem conceitual do conteúdo, intercalando-se questões envolvendo cálculos e o último encontro foi destinado à avaliação de todas as etapas do processo. A análise dos dados revela que as turmas obtiveram ganhos significativos de aprendizagem. Observou-se que as discussões entre os colegas foram proveitosas, propiciando a participação dos alunos como protagonistas do seu próprio processo de ensino-aprendizagem e levaram a um aumento do percentual de acertos das questões conceituais propostas. O retorno dado pelos alunos demonstra que a dinâmica da aula os motiva a trabalhar e os mantêm envolvidos com o trabalho por mais tempo. Conclui-se que esta sistemática pode se estender a outros conteúdos da Física, aumentando a interação entre os alunos e a reflexão crítica sobre os fenômenos que estão sendo abordados. Para a aplicação desta proposta foram elaboradas: tarefas prévias, os momentos da sequência didática e um banco de questões conceituais. / This work aimed to develop a high school level didactical sequence about Newton’s Laws of motion, suitable for use with Peer Instruction teaching method. This didactical sequence was implemented in four first grade classes (totaling 118 students) of a public technical High School in Novo Hamburgo (Brazil). The conception of all material was based on David Paul Ausubel’s Meaningful Learning Theory. The classes were organized in seven meetings of one hour and forty minutes each. The Peer Instruction method was used for conceptual learning during six of these meetings, interspersing questions involving calculations. The last meeting was dedicated to evaluate all the stages of the process. The performance analysis of the data reveals that the students obtained significant learning gains. The discussions among the students were useful, allowing the participation of students as protagonists of their own teaching-learning process and led to an increase in the percentage of correct answers to the proposed conceptual questions. The feedback given by the students demonstrates that the dynamics of the class motivates them to work and keeps them involved with the work. We can conclude that this systematics can be extended to other contents of Physics, stimulating the interaction between the students and the reflection on the phenomena that are being approached. For the application of this proposal were elaborated: previous tasks, a didactical sequence in moments and a bank of conceptual questions.

This work provides a fundamental view of the mechanisms which affect the power efficiency of communications processes along with a method for efficiency enhancement. Shannon's work is the definitive source for analyzing information capacity of a communications system but his formulation does not predict an efficiency relationship suitable for calculating the power consumption of a system, particularly for practical signals which may only approach the capacity limit. This work leverages Shannon's while providing additional insight through physical models which enable the calculation and improvement of efficiency for the encoding of signals. The proliferation of Mobile Communications platforms is challenging capacity of networks largely because of the ever increasing data rate at each node. This places significant power management demands on personal computing devices as well as cellular and WLAN terminals. The increased data throughput translates to shorter meantime between battery charging cycles and increased thermal footprint. Solutions are developed herein to counter this trend. Hardware was constructed to measure the efficiency of a prototypical Gaussian signal prior to efficiency enhancement. After an optimization was performed, the efficiency of the encoding apparatus increased from 3.125% to greater than 86% for a manageable investment of resources. Likewise several telecommunications standards based waveforms were also tested on the same hardware. The results reveal that the developed physical theories extrapolate in a very accurate manner to an electronics application, predicting the efficiency of single ended and differential encoding circuits before and after optimization.

School science education prepares learners to study science at a higher level, prepares them to follow a career in science and to become scientific literate citizens. It is the responsibility of the educator to ensure the learners’ conceptual framework is developed to the extent that secures success at higher level studies. The purpose of this study was to test the effectiveness of conceptual change teaching strategies on the conceptual development of grade 11 learners on Newton’s second law of motion. The two strategies employed were the cognitive conflict strategy and the development of ideas strategy. A sequential explanatory mixed-method research design was used during this study. The qualitative data were used to elucidate the quantitative findings. The quantitative research consisted of a quasi-experimental design consisting of a single-group pre-test–post-test method. During the qualitative part of the research a phenomenological research approach was utilised to gain a better understanding of participants’ learning experiences during the intervention. The quantitative research made use of an adapted version of the Force Concept Inventory (FCI). The data collected from the pre-test were used to inform the intervention. The intervention was videotaped and the video analysis or qualitative data analysis was done. After the intervention the post-test was written by the learners. Hake’s average normalised learning gain <g> from pre- to post-scores was analysed to establish the effectiveness of the intervention. The two sets of results (quantitative and qualitative) were integrated. Information from the qualitative data analysis was used to support and explain the quantitative data. The quantitative results indicate that there was an improvement in the students’ force conception from their initial alternative conceptions, such as that of an internal force. Especially the learners’ understanding of contact forces and Newton’s first law of motion yielded significant improvement. The qualitative data revealed that the understanding of Newton’s second law of motion by the learners who partook in this study did improve, since the learners immediately recognised the mistakes made when confronted with the anchor concept. The cognitive conflict teaching strategy was effective in establishing the anchor concept of force which proved to be useful as bridging concept in the development of ideas teaching strategy. The data from both datasets revealed that the cognitive conflict teaching strategy for the initial part of the intervention was effective. It was evident that for development of the idea teaching strategy the two data sets revealed mixed results. Recommendations were made for future research and implementation of conceptual development teaching strategies. / MEd (Natural Sciences Education), North-West University, Potchefstroom Campus, 2014