Reflexões e contribuições para o ensino de gravitação clássica no nível médio

The subject of Classic Gravitation is part of the actual curriculum for High School in Brazil, and it is taught in the first year of that education level. This master thesis presents a research regarding the subject Classic Gravitation in High School. This research was based in two complementary guidelines of research and action. The first guideline was the analysis of 21 didactic books of physics which are the more frequently used in High School, in the city of Natal/RN. The second guideline, worked after being verified the most common deficiencies presents in the didactic books, was the elaboration, followed by a practical application, of a course suggesting how to approach that subject in the classroom. The Parâmetros Curriculares Nacionais para o Ensino Médio (National Curricular Parameters for High School PCNEM) defend that Classic Gravitation is very important in the student s formation and that its study helps the comprehension of many nature s phenomena. Because of this vision of that subject by the PCNEM, the 21 analyzed books were separated in two groups: the first one, containing 10 books, was edited before the spreading of PCNEM, and the second, with 11 books, after that spreading. Whatever the group to which the didactic books belonged, the great majority of them let that subject in a second plan; two of them even suggesting, in the teacher s orientations, that the subject Gravitation can be suppressed in case of insufficient time . These analyses points that the PCNEM had produced no changes in the conception of the authors that wrote books regarding that subject. To analyze the didactic books, we elaborated a script which was used as an analysis tool, in which we put in evidence the relative importance of the historic and philosophic contextualization of the subject, the quotidian experience of the students and the interdisciplinary approach, among other aspects. It became evident that the didactic books give very little emphasis to historic aspects of the knowledge construction, to the relations with the day-by-day questions and to the interdisciplinary character of the subject Gravitation. It calls attention the non concordance among the authors opinions regarding the necessary previous knowledge or prerequisites the students should fulfill in order to begin to study Gravitation. The course we elaborated was given to a group of teachers as well as to students. In those courses we treated theoretical and practical aspects and emphasized historical questions and the ones which are related to people s daily life. The course for teachers was realized as an extra-mural activity of the UFRN and was given by the author of this thesis at the Escola Estadual Francisco Ivo Cavalcanti (a state public school in Natal/RN). There were 23 teachers present, from several public schools and several fields of knowledge. The thesis supervisor and the master degree s colleagues of the author acted as collaborators , reporting the participants opinions and speeches. The course to the students, on the other hand, had the participation of 300 regular students who belonged to 6 different 1st year classes of the High School Escola Marista de Natal (RN), in which the author acts as a physics teacher. The student s course was realized as part of the regular curriculum activities, in which three classes stood under the responsibility of the author and other three classes in charge of another Marista s teacher, who participated as a collaborator . The teacher s course as well as the students one were given in two stages, with five hours each. The first stage was divided in two moments, the first one focused on the survey of the spontaneous conceptions about gravitation, in which we worked basically with experiments of free throwing and pendulum, and the second one focused in theoretical presentations and quarrels about universe s models. In the second stage of the course we improved the study of Kepler s laws and the Newton s Universal Gravitation law, and we used as motivating tools some practices involving the construction of the solar system in scale. As instruments for evaluating both courses we used questionnaires and reported the speeches with participants opinions, beyond usual written evaluations in the course for the students. The teachers who participated in the course showed very good wills in realizing interdisciplinary practices; nevertheless, according their own speeches, they frequently came across the difficulty of how to do . From the experience we had in both courses, we conclude that the approach we propose hear to the teaching of the subject Classic Gravitation , supported on the tripod theory, practice and historical and philosophical aspects, is viable and effective. One hopes that this research may contribute in the formation of a opinion, among the teachers, concerning how to approach the subject of Classic Gravitation, and may offer suggestions in order those who want to apply that approach may develop classroom practices aiming to improve the teaching of that subject, which has a singular importance in the formation of High School students

Identificação das políticas de incentivo ao desenvolvimento da energia eólica no Rio Grande do Norte (RN)

Energy is a vital resource for social and economic development. In the present scenario, the search for alternative energy sources has become fundamental, especially after the oil crises between 1973 and 1979, the Chernobyl nuclear accident in 1986 and the Kyoto Protocol in 1997. The demand for the development of new alternative energy sources aims to complement existing forms allows to meet the demand for energy consumption with greater security. Brazil, with the guideline of not dirtying the energy matrix by the fossil fuels exploitation and the recent energy crisis caused by the lack of rains, directs energy policies for the development of other renewable energy sources, complementing the hydric. This country is one of the countries that stand out for power generation capacity from the winds in several areas, especially Rio Grande do Norte (RN), which is one of the states with highest installed power and great potential to be explored. In this context arises the purpose of this work to identify the incentive to develop policies of wind energy in Rio Grande do Norte. The study was conducted by a qualitative methodology of data analysis called content analysis, oriented for towards message characteristics, its informational value, the words, arguments and ideas expressed in it, constituting a thematic analysis. To collect the data interviews were conducted with managers of major organizations related to wind energy in Brazil and in the state of Rio Grande do Norte. The identification of incentive policies was achieved in three stages: the first seeking incentives policies in national terms, which are applied to all states, the second with the questionnaire application and the third to research and data collection for the development of the installed power of the RN as compared to other states. At the end, the results demonstrated hat in Rio Grande do Norte state there is no incentive policy for the development of wind power set and consolidated, specific actions in order to optimize the bureaucratic issues related to wind farms, especially on environmental issues. The absence of this policy hinders the development of wind energy RN, considering result in reduced competitiveness and performance in recent energy auctions. Among the perceived obstacles include the lack of hand labor sufficient to achieve the reporting and analysis of environmental licenses, the lack of updating the wind Atlas of the state, a shortfall of tax incentives. Added to these difficulties excel barriers in infrastructure and logistics, with the lack of a suitable port for large loads and the need for reform, maintenance and duplication of roads and highways that are still loss-making. It is suggested as future work the relationship of the technology park of energy and the development of wind power in the state, the influence of the technology park to attract businesses and industries in the wind sector to settle in RN and a comparison of incentive policies to development of wind energy in the Brazilian states observing wind development in the same states under study.