WHAT ENGINEERING STUDENTS UNDERSTAND ON THE FIRST PRINCIPLE OF ENERGY IN MECHANICS AT INTRODUCTORY PHYSICS COURSES?

New research in Science Education have generated teaching models which agree that learning is being able to justify what one thinks and, that production processes and acceptance (justification) of developed knowledge in everyday life are different from those characterizing scientific work and school work. Recently, the Report to the European Commission on Improving the Quality of Teaching and Learning in Europe’s Higher Education Institutions highlights the importance of presenting science as a creative process that draws up theories and concepts as tentative solutions to problems presented by Scientists and Society. From this orientation, this study will focus on the description of undergraduate students’ understanding as data on which teachers can base their decisions about intervention to assist student learning. The data also indicates ways of improving teaching sequence designs so as to measure development of understanding. This study describes some outcomes from research into assessment of students’ levels of understanding of some key concepts and principles in the context of first principle of energy in the area of Mechanic.

Relations between work and energy are still a source of teaching-learning problems in the first years of university introductory physics courses, since they involve very abstract concepts and skills of scientific methodology. The research on teaching energy has shown evidences of the little learning achieved by secondary students but few studies have been developed at university level.

Taken into account the previous studies, the principal objective of the study presented here was to identify and document specific difficulties that students displayed while thinking and reasoning about the calculation of work and the application of first principle of energy in isolated systems with one particle. Our major research questions are the following:
a) What is the students’ understanding on the concept of work for a single particle systems?;
b) Do students understand the work-kinetic energy theorem?

The research consists of two designs:
a) four written questions;
b) videotaped interviews with group of students when solve a problem.

The questionnaire data were collected in exams that were part of the evaluation system. Interviews were proposed to groups of students as part of their training in problem solving. The sample consists of 165 first-year students of Engineering.

In the presentation will present two of the questions. The first results show that many students failed to come to a satisfactory final solution for the calculation of work and for the justification of the first energy principle. Our written data suggest that students have misunderstanding in making relation between work done and energy change in the contexts of force acting on an object. We will describe in the presentation the specific misunderstanding and the students´ type of alternative reasoning that they use.