In order to fix some important concepts of Fundamental Physics, either because they are not usually discussed in depth in theoretical classes and much less at laboratories, or because they are not sufficiently developed in textbooks, it is more effective not to tackle them directly, but to propose a mental or practical experiment to attract the…

Given the great interest that black holes arouse among non-specialists, it is important to analyse misconceptions related to them. According to the author, the most common misconceptions are that: (1) black holes are formed from stellar collapse; (2) they are very massive; (3) they are very dense; (4) their gravity absorbs everything; and (5) they…

According to Newtonian mechanics, the gravitational fields created by bodies with spherical symmetry (such as planets) are non-uniform. This may create the impression to undergraduate physics students that uniform gravitational fields are just an approximation. This is not the case as uniform gravitational fields are created in hollows of…

A popular physics legend holds that scissors can cut paper with a speed faster than light. Here this counter-intuitive myth is investigated theoretically using four simple examples of scissors. For simplicity, all cases will involve a static lower scissors blade that remains horizontal just under the paper. In the first case, the upper blade will…

The concept of a sinusoidal wave traveling along a string is included in all secondary education physics books and as a result is being taught in undergraduate lectures around the globe. The didactic approach that follows is advantageous since it provides in a simplified way (through basic mathematical tools) a description of a disturbance that…

This work is aimed to assess the performance of two groups of students from colleges of Science, Education and Engineering on the understanding of electricity and magnetism concepts. To conduct this assessment, the Electricity and Magnetism Conceptual Assessment (EMCA) test was implemented twice as a pre-test and a post-test for two calculus-based…

The purpose of this study was to provide an online astronomy activity using the Stellarium program as a virtual planetarium. The implementation was conducted with 30 preservice primary school teachers (PPTs) who participated in a non-formal workshop that included interactive, technology-based astronomy practices embedded with the…

Teaching cosmology at the undergraduate or high school level requires simplifications and analogies, and inevitably brings the teacher into contact with at least one of the pedagogical interpretations of the expanding Universe. The by far most popular interpretation holds that galaxies in an expanding Universe are stationary, while space itself…

We started this work with the goal of detecting misconceptions held by our students about force and motion. A total of 341 students participated in this study by taking the force concept inventory (FCI) test both before and after receiving instructions about force or motion. The data from this study were analysed using different statistical…

Graphs in physics are central to the analysis of phenomena and to learning about a system's behavior. The ways students handle graphs are frequently researched. Students' misconceptions are highlighted, and methods of improvement suggested. While kinematics graphs are to represent a real motion, they are also algebraic entities that must satisfy…

The purpose of this work is to study the effectiveness of our introductory mechanics instructions in changing students' misconceptions about Newtonian concepts. We gave the force concept inventory (FCI) test to 341 of our students twice, before and after instructions. The data were analyzed using a method first reported by Martín-Blas "et…

We propose the use of smartphone-based slow-motion video analysis techniques as a valuable tool for investigating physics concepts ruling mechanical wave propagation. The simple experimental activities presented here, suitable for both high school and undergraduate students, allows one to measure, in a simple yet rigorous way, the speed of pulses…

Tablet computers were used as experimental tools to record and analyse the motion of a ball thrown vertically from a moving skateboard. Special applications plotted the measurement data component by component, allowing a simple determination of initial conditions and "g" in order to explore the underlying laws of motion. This experiment…

This paper revisits a well-known hydrostatic paradox, observed when turning upside down a glass partially filled with water and covered with a sheet of light material. The phenomenon is studied in its most general form by including the mass of the cover. A historical survey of this experiment shows that a common misunderstanding of the phenomenon…

This paper presents the results of the first survey conducted in Belgium about the interest in and knowledge of astronomy. Two samples were studied, the public at large (667 questionnaires) and students (2589 questionnaires), but the results are generally similar in both samples. We evaluated people's interest, main information source and…