Diseño de una secuencia didáctica para la enseñanza aprendizaje del concepto de torque a partir de las máquinas simples

Abstract

Construcción del concepto de torque teniendo en cuenta los conceptos previos y algunas aplicaciones en las máquinas simples. Se parte del proceso histórico epistemológico de la palanca hasta el desarrollo de la ley de la palanca de Arquímedes, mediante actividades significativas que estructuran el concepto para aplicarlo en diferentes contextos.

Abstract. The importance of teaching torque in physics is based on the concepts which are involved in it’s construction and in the different practical applications as the use of simple machines that awakes the student’s interest. The research work starts with a historical overview of the historical-epistemological concept of torque taking into account the uses of the levers in the past until the development of the law of Aquimedes on levers. Then the disciplinary aspects related to the concept of torque are revised until it’s definition is deduced in terms of the arm of the lever times the applied force. The torque is also defined as the product of the inertia moment times the angular aceleration. For the development of the investigation a research was done about the design of educational sequences, it’s structuture and the learning environments. Following the results that were found, a teaching sequence is proposed for the teaching and learning of torque with the objective of a significant learning. The sequence starts with a pre-test in which difficulties on the use of the Newton laws were observed, so activities to reinforce are proposed. After this an introduction to the concept of torque is given by the acknowledgment of some tools and devices in the context of the main theme. The concept of torque is then constructed by identifyng the rotational axis, the arm of the lever and the applied force in different examples to finally give a definition to it. The equilibrium conditions, levers and pulleys are explained too as the best examples to understand the concept of torque. At last the work is guided to solve problems and learn practical applications. Finally after applying the post-test better individual results are observed with a high level performance. Moreover the students showed motivation and improved their argumentation abilities and most of them changed their prior ideas about equilibrium. By this it can be said that the suggested proposal was enriching for the teaching of the concept of torque.