Princípios da termodinâmica e mecânica: motor térmico de elásticos
Resumo
Teaching physics has always been a challenge for teachers. It is usually based on expository lessons and application of mathematical formulas, providing only a process of memorization of contents and resolution of exercises aimed to college admission exams. In this perspective the students usually do not see much use in studying Physics, by further worsening the scenario for lecturing and learning Physics. One of the most widely studied methodologies for Physics teaching is the experimentation. Although scientific experiments attract the attention of students, it is almost not applied in the classroom, either for lack of time to check the capabilities of the experiment or lack of proper space to perform the activities. Motivated by a group of students with below-average grades in a private high school in Campinas city, São Paulo state, we developed in this work an educational product in which we consider both theoretical classes and demonstrative experiments in a complementary way. Our mainly objective is to make Physics learning more effective by providing a better student-teacher interaction. Using the investigation as the procedure conducted in the experimentation the student can play an active role in the process of knowledge construction with the teacher as a mediator. Two experiments were set up for this purpose: a pendulum made of rubber band and a massive weight, which was used to show the anomalous dilatation of rubber, and the rubber band heat engine, cited by Richard Feynman in his lectures, to show how a heat engine works according to the laws of Thermodynamics and Mechanics. With these experiments we worked many concepts such as heat, thermal expansion, the laws of Thermodynamics, heat engines, torque, center of mass and many others. Our proposal was successfully applied. The students were motivated for attending the classes, questioning and creating hypotheses through the supervision of the teacher, showing that the methodology used is promising to improve students' motivation and performance in Physics classes.