Investigation of students' knowledge application in solving physics kinematics problems in various contexts

Abstract

The topic of students’ application of conceptual knowledge in physics is constantly being researched. It is a common occurrence that students are able to solve numerical problems without understanding the concepts involved. The primary focus of this dissertation is to investigate the extent to which a group of first year physics students are able to identify and use the correct physics concepts when solving problems set in different contexts. Furthermore, this study aims to identify underlying factors giving way to students not applying appropriate physics concepts. A questionnaire was designed in test-format in which all the problems dealt with two objects whose movement had to be compared to each other. The physical quantities describing or influencing the objects’ movement differed in each consecutive problem; whilst the nature of the concept under consideration remained the same. The problems were set in various contexts namely: i. Formal conceptual questions, some with numeric values; ii. Questions set in every day context with/without numeric values; iii. Questions on vertical upward, vertical downward and horizontal motion. The questionnaire was distributed to 481 students in the first-year physics course in 2014 at the Potchefstroom Campus of the North West University. It was expected that the percentage of correct answers would reveal discrepancies in the responses to contextual, numeric and formal conceptual questions. The outcome of the statistical analysis confirmed this expectation. In addition, it seemed that only a few students were able to correctly identify the appropriate variables when considering vertical and horizontal movement while the majority of the students did not apply the same physics principle in isomorphic vertical upward and vertical downward problems. It appears that the context in which the question was posed determined whether the problem was seen as an item that would require “physics reasoning” or as a setting where physics reasoning did not apply. The results revealed students inability to relate physics concepts to appropriate mathematical equations. Two important results from this work are: (1) the presentation of a questionnaire that can be implemented to investigate various aspects regarding the contexts of physics problems; and (2) expanding the concept of context to include the direction of movement as a separate context.