A geração de energia elétrica de corrente contínua (CC) e de corrente alternada (CA) através de práticas de fácil execução

Abstract

Due to the growing global demand for energy, especially electricity, research is looking for new ways to generate it, as well as to disseminate, explain and teach it. The topic in question is necessary, not only in academia but also in basic education. Thus, this work sought to provide third-year high school students with a wealth of historical, theoretical and experimental information about the consumption and saving of electrical energy, about what it is and how direct electrical current can be generated. (CC) and alternating (CA), using materials that are simple and easy to acquire. Two diagnostic questionnaires of 10 questions were applied for students to answer, one at the beginning and the other at the end of this proposal, with the intention of respectively identifying prior knowledge and after application of the work, thereby evaluating the evolutionary result of the class in relation to to the theme of the work. The topics were addressed in 16 meetings, theoretical classes, face-to-face, video conferences, YouTube videos and practical face-to-face experiments. When carrying out the experiments, the procedure was as follows: i) To generate direct current in a closed electrical circuit, electrolytic solutions were used with electrical terminals made of different metallic materials that did not touch each other and were simultaneously in contact with this solution, photoelectric plates, Faraday disk DC generator (consisting of a metallic disk rotating with constant angular speed, with the surface of the disk crossed by a constant magnetic flux, then appearing an electrical potential difference established at different points, located at different distances in relation to the center disk); ii) To generate alternating current in a closed electrical circuit, a mini AC generator was built using an injection syringe with enamel wire wrapped around it, forming a coil and four neodymium magnets were placed inside the syringe in motion. oscillatory. At the end of the meetings, the topic relating to electricity consumption and saving was discussed with the students, where the school's electricity consumption over several months was analyzed and the students proposed ways to save it. It is also important to highlight that the work was developed following the pedagogical concepts of Vygotsky's socio-constructivism, seeking social interaction between students, making them acquire knowledge and evolving through cooperation among themselves. Vygotsky also used the concept of Zone of Proximal Development (ZPD), which deals with how knowledge is related and the way in which its construction occurs. Thus, the work was completed, helping to awaken new interests and vocations.