Aproximações no ensino de física: o estudo do pêndulo simples

Abstract

The use of approximations in Physics is very common and necessary to enable our understanding of fundamental aspects of the nature working. The purpose of this work is to clarify that the use of approximations is not a logical crime as long as the limitations inherent to these approximations are clear to the investigator. We address the approach used in the study of a simple pendulum, where it is adopted, for small oscillations 𝑠𝑖𝑛𝜃 ≅ 𝜃, in order to facilitate its quantitative investigation. An experimental apparatus was developed to collect empirical data, some possible correlations of the pendulum period with its constructive characteristics were analyzed, limiting the study to the direct dependence of the period with its length, thus achieving an empirical equation, capable of performing period predictions for a given length. In addition, the study of error theory was did in order to clarify its use in experimental studies, showing its importance at the time of analyzing the data obtained from an experiment, seeking to clarify the reason why some terms of minor importance can or cannot be left aside in the study of a physical phenomenon. Finally, it was sought through this approach to treat Physics not as an exact science, but as a science of good approximations, which makes it even more instigating, as a natural philosophy.