Revista Mexicana de Física E

Calculation of the Wigner angle by means of vectors

2024-02-25T22:08:49+00:00

It is shown that each Lorentz transformation leaving invariant one spatial axis can be represented by a single complex vector. This fact is employed in the calculation of the Wigner angle (which arises in the composition of two boosts in arbitrary directions) and of the aberration of light.

Método de iteración asintótica: átomo de hidrógeno, grafeno, modos cuasi normales

2024-06-20T21:21:18+00:00

En este trabajo se muestra como el Método de Iteración Asintótica (AIM por sus siglas en inglés) puede ser empleado para obtener eigenvalores y eigenfuciones en diferentes campos de la física. Partiendo de la ecuación de Schrödinger en cada caso, se pueden calcular la energía y las funciones de onda del Átomo de Hidrógeno o los modos cuasi--normales en el caso de agujeros negros. El objetivo central, es mostrar cómo aplicar el Método de Iteración Asintótica en algunas áreas de la Física.

In this work, we show how the Asymptotic Iteration Method (AIM) can be used to obtain eigenvalues and eigenfunctions in different fields of physics. Starting from the Schr\"odinger equation in each case, the energies and wave functions of the Hydrogen Atom or the quasi-normal modes in the case of black holes can be calculated. The central objective is to show how to apply the Asymptotic Iteration Method in some areas of Physics.

An analysis of the motion of Hombo Batu jumping in nias using trackers, GNU octave and spreadsheets

2025-05-28T23:57:30+00:00

Culture is one of the teaching materials in education. But in reality, it is still rare to use culture in teaching because education and culture look like two different things. Culture and education are considered separate things, even though the former is important to be integrated into the latter so that it is sustainable. Students can learn Indonesian culture through cultural integration in education that follows the trend of digitization so that they learn science meaningfully according to the demands of the times. This research aims to use tracker software, GNU Octave and Spreadsheet to visualize the parabolic motion of Hombo Batu jumpers and as an alternative learning tool. Euler Cromer’s method was used in the GNU Octave Software and compared the results with Software Tracker. Hombo Batu jumper movements were recorded, and then analysed using tracker software. Data processing was done through a manual process using the parabolic motion formula and the law of conservation of mechanical energy. This tracker software can analyse the video on each tracker. This research used the experimental method. The experiment incorporates a video from YouTube, a tracker, and spreadsheets. The data collection was through tracker experiments, literature studies, and documentation. The data analysis used descriptive techniques. This paper succeeds in making parabolic motion visualization of Hombo Batu jumpers in Nias in ethnoscience-based learning to develop students’ thinking skills analytically and numerically. Software Tracker and Spreadsheet are easier to use because they don’t use a complicated programming language like GNU Octave. The experimental results show that through a tracker the value of the acceleration of gravity in the Hombo Batu jump is 9.38 m/s2 . This shows that the Hombo Batu jumping movement in Nias can be integrated through an ethno-scientific approach so that students can learn science from Indonesian culture. Trackers and spreadsheets can help students think analytically, so they should be used in other learning materials as well. Trackers and spreadsheets can be used as an alternative to learning parabolic motion.

Using Desmos for visualizing Fourier series in mathematical a physics course

2024-08-04T17:45:59+00:00

The Fourier series has been used widely to model various physical phenomena. It becomes a core concept taught in mathematical physics courses. To help students understanding the concept and interpretation of the Fourier series, we propose the utilization of the Desmos application in the classroom. Desmos has a feature of a graphing calculator that can be used for visualizing a function without programming. With an appropriate teaching approach, the Fourier series can be understood more easily.

The effectiveness of a physics e-book on rotational dynamics of a traditional top game assisted by augmented reality to improve students’ critical thinking skills and visual representations

2024-08-09T00:06:28+00:00

This study aims to determine the effectiveness of the physics e-book of rotational dynamics in the traditional game of augmented reality-assisted tops in improving students' critical thinking skills and visual representation. This type of research is Research and Development (R&D) using the ADDIE development model, namely analyse, design, develop, implement, and evaluate. This research design is pretest-posttest control group. The subjects of this study included 3 expert lecturers and 2 teachers for product validation, 5 expert lecturers and 2 teachers for instrument content validity, 254 students for empirical validity of the instrument, 6 students for product readability test and 81 students for implementation test. The data analysis technique of this research is to test the feasibility of the product using a standard scale, for the content validity of the instrument using Aiken's V, to analyse the items using the Partial Credit Model, and to test the effectiveness of the product using the general linear model (GLM). The results of this study indicate that the use of rotational dynamics physics e-books on traditional games of augmented reality-assisted tops is effective in improving critical thinking skills and visual representation of students with a large effect size category.

Analysis of a system of two masses linked by a rope with variable tension including a friction force

2024-08-29T19:25:37+00:00

The effect of a friction force on a system consisting of a two masses connected by a rope passing over a frictionless pulley is investigated. One mass slides on a horizontal surface with friction while the other mass moves vertically. The motion equation is obtained and its numerical solution is computed using the GNU Octave package. The experimental data are obtained using a data acquisition system and the Tracker video analyser. The graphs are made using the Origin software. The vertical position of one of the masses in function of the time can be represented by an exponential expression of the form y(t)=a b^t. The comparison between theoretical an experimental results gives that the lowest average relative error is obtained with the Tracker.

Teaching of tension force: a massive rope in equilibrium

2024-08-02T23:57:00+00:00

A massive rope in equilibrium, with fixed extremes, takes a particular shape as a consequence of both, the weight and tension on each small rope segment. An analysis of forces acting on each rope infinitesimal section under static equilibrium conditions, results in a differential equation with a solution that provides the general shape of the rope and from which, the tension on each point of the rope is obtained. From this theoretical treatment a set of three rules are proposed. They allow to create and to solve a variety of theoretical and experimental problems dealing with tension force applied to massive ropes under static equilibrium conditions. The teaching experience with first-year engineering students shows that they deduced the rules and solve different problems. Also, it provides to the teacher possibilities to teach tension force in massive rope at basic physics level. The first approaching to test the didactic-proposal was developed into collaborative learning framework. However, it can be configure to suit pedagogical needs.

Agujeros negros rotatorios: La más fantástica fuente de energía del universo

2024-08-16T21:10:50+00:00

Los agujeros negros rotatorios son la fuente de energía más poderosa del universo conocido, y son la causa de algunos de los fenómenos astronómicos más espectaculares y extremos. El objetivo de este artículo es analizar en términos simples la física de la extracción de energía en agujeros negros rotatorios. Concretamente se analiza la fuente de dicha energía, la eficiencia del proceso de extracción energética, y algunos mecanismos concretos que permiten dicha extracción. El artículo está destinado principalmente a estudiantes no graduados de física, astronomía y carreras afines.

Rotating black holes are the most powerful source of energy in the known universe, and are the cause of some of the most spectacular and extreme astronomical phenomena. The goal of this article is to analyze in simple terms the physics of energy extraction in rotating black holes. Specifically, the source of said energy, the efficiency of the energy extraction process, and some specific mechanisms that allow said extraction are analyzed. The article is intended primarily for undergraduate students of physics, astronomy and related fields.

A simple proposal to measure the Planck’s constant h with a ESP32 development board

2024-09-04T20:01:20+00:00

Planck’s constant h plays a fundamental role in the quantum theory. The numerical value of this universal constant can be experimentally obtained in a wide variety of physical phenomena. Determining the numerical value of h using LEDs and identifying the threshold voltage in which these devices emit light has become a favorite example of obtaining a rather precise value of h with a simple and cheap experimental setup. In this article, we propose a laboratory exercise with a fully automatized data acquisition framework based on a development ESP32 board. We used four LEDs of different colors, which were separately characterized by their wavelength. Each LED was fed, and the light intensity was measured. The threshold voltage was determined for each of the colors we considered, and then h was determined within fairly good deviation from the world average value. Moreover, using this world average value of h we determined the deviation of the wavelength of an ultraviolet LED from the manufacturers quoted value with remarkably good agreemen.

Critical thinking skills profile in the ETNO-STEAM science learning model implementation in the university: A case study

2024-08-23T21:24:24+00:00

Students' ability to comprehend how concepts from science, technology, engineering, art, and mathematics can be used in the cultural setting in which they live can be improved through the study of ethno-STEAM. Students that possess critical thinking abilities can solve complex issues, broaden their viewpoints, and make better decisions. This study's objective is to investigate the profile of critical thinking abilities among children who are learning science utilizing an Ethno-STEAM approach. The qualitative case study research approach was used in this study. 46 students were selected in the research sample using a non-probability purposive sampling technique. An open description test of critical thinking abilities was used as a test technique in this study, along with non-tests such in-depth interviews and non-participatory observation. Data preparation, indexing, category and theme formatting, thematic analysis, and reporting are all aspects of data analysis. The study's findings suggest that students have good problem-solving abilities. Student communication abilities are also quite strong, as seen by their capacity to convey knowledge despite heavily relying on literature. Students' generalization skills have not yet been put to the test by generalizations that are narrowly focused on one scientific field. Reflection is now possible, although there are still a number of unidentified problems. Students have outstanding execution abilities when it comes to using their knowledge to solve challenges. The ability to blend information from other fields to recognize more intricate interrelationships when handling a case also contributes to student self-regulation. The results of this study provide important findings that students have demonstrated a profile of critical thinking skills that is extremely adequate through the application of the Ethno-STEAM science learning. So that they may continue to adapt to the times and preserve the culture around them, this can assist students develop their skills in tying science, technology, and engineering to culture

Modeling reflection and refraction of freeform surfaces

2024-09-13T19:21:04+00:00

In this work, we present a detailed procedure for computer implementation of the laws of refraction and reflection on an arbitrary surface with rotational symmetry with respect to the propagation axis. The goal is to facilitate the understanding and application of these physical principles in a computational context. This enables students and instructors alike to develop simulations and interactive applications that faithfully replicate the behavior of light and sound propagating in a diversity of media separated by arbitrary surfaces. In particular, it can help to explore freeform optics. Additionally, we include a practical example demonstrating these implementations using either Matlab or open-source Octave programming language.

Improving the critical thinking skill of high school students: The context of tracker software applications

2024-08-02T02:40:10+00:00

This study aims to improve students' critical thinking skills using the tracker software application. The research design used was a pre-experimental design with a one-group pretest-posttest design model. The sample in this study were all students of class X IPA 5 totaling 34 students. Sampling was done by simple random sampling technique. The data collection methods used were tests, documentation, and observation, while the Wilcoxon and N-gain tests were used to analyze the data. The result of the Wilcoxon test using SPSS IBM 25 shows the sig. 2-tailed is 0.000, meaning that the value is <0.05 so that Ha is accepted. The N-gain results obtained were 70% and included in the medium category. Thus, this study proves that the use of a tracker software application can improve students' critical thinking skills in Work and Energy material for class X IPA 5 SMA Negeri 3 Yogyakarta.

Improving problem-solving skills through the physics education technology assisted problem based learning model electronic student worksheets

2024-02-04T20:27:36+00:00

The 21st century requires learning activities to put different skills into practice. Solving problems is a skill that pupils need to possess in order to succeed in the twenty-first century. In order to be able to propose strategic solutions to the problems that are presented and conclude with an evaluation of the solutions that have been chosen, students need to have the ability to analyze facts and test assumptions. The goal of this project was to create an Electronic Student Worksheets Science based on physics education technology that utilized problem based learning to assess students’ problem-solving abilities. The 4D development model, which is separated into define, design, develop, and disseminate, is the development methodology utilized to create the electronic student worksheet product. The masyithoh gamping foundation madrasah tsanawiyah islamic school equivalent to junior high school hosted the product trial in May 2023. Even semester VIII grade students were used as research test subjects with an age range of 13 to 14 years. The physics material chosen in this study is in the chapter on changes in the form of substances. Ten VIII grade students grouped into low, medium, and high categories were used as test subjects. The trial was carried out using a quasi-experimental method with a one group pretest posttest design by giving individual initial tests before carrying out learning activities and then giving a final test after carrying out the activities. This activity has 2 stages, the first is a direct experimental activity by making observations, while the second activity uses the help of physics education technology. The activity is carried out by creating two groups each consisting of four or five students, who participate in the experiment. Next, the final test is given individually to each student. A total of 90% of students gave a positive response (very good) to the science electronic student worksheets in this study, according to the findings of the reading of the questionnaire given to students. Based on the findings of the analysis, 90% of students can easily learn with the help of electronic student worksheets. It can be said that after receiving the electronic student worksheets IPA treatment, students’ ability to solve problems increased.

Cartesian Isotropic Tensors for Beginners

2024-10-23T21:15:30+00:00

In this paper, we show how to find the isotropic tensors from rank one to four and suggest a way to calculated higher orders following one of the methods exposed here. We describe two methods for calculating the isotropic tensors from rank one to four, almost step by step. An explicit representation of the components of the isotropic tensor from rank one to four is given.

Adding an Einsteinian motivation to key moments in an electromagnetism course

2024-10-24T02:53:38+00:00

This paper aims to provide physics teachers with tools to help deepen the understanding of the laws of electromagnetism. The fundamental contributions of our proposal are: a) to use quotes from mythical characters in the history of science as a motivating educational resource; b) to promote the discussion of striking and fundamental topics; c) to mention diverse approaches and stimulate the search for correct answers to provocative questions. Citations from Einstein refer to principal contributions made by Newton, Maxwell and himself. Emphasis is placed on the cognitive value of differential (local, infinitesimal) analysis of fundamental concepts (field structure, causality, field relativistic transformations). The electromagnetism unity is analyzed from the point of view of special relativity. It is clarified that descriptions suggesting that the magnetic field is dispensable are contrary to the Einsteinian approach: they assume that, to describe the interaction between moving charges, there is a preferred coordinate system for each particular problem. An introductory presentation of the tensor form of Maxwell’s equations is provided.

Facilitating students’ analytical thinking skill and scientific attitude in distance learning using local wisdom-based physics PBL E-module

2024-10-17T20:33:09+00:00

The cultivation of 21st-century competencies can be facilitated through the study of physics, particularly focusing on the concept of elasticity. Elasticity, a fundamental concept in physics, demands analytical thinking and a scientific mindset for problem-solving within its domain. Employing a problem-based learning approach tailored to elasticity material, students are guided to engage with real-life issues intertwined with local knowledge. This pedagogical strategy aims to enhance students’ comprehension of elasticity principles by contextualizing them within familiar scenarios. This experimental study aims to assess: 1) the effectiveness of the Local Wisdom-based Physics PBL E-module to improve the student’s analytical thinking skills, 2) the effectiveness of using the Local Wisdom-based Physics PBL E-module in improving student’s attitudes toward science. This experimental research used pretest-posttest control group design. The selection of the research sample used the cluster random sampling method in 11th-grade students from the Natural Science program at MAN (Islamic Senior High School) 1 Yogyakarta, Indonesia. The data collection instruments used were pretests-posttets questions, and a scientific attitude questionnaire, yielding quantitative data. Analysis of data was carried out by descriptive statistical analysis using normalized gain. Inferential statistical analysis used normality, homogeneity, correlation, MANOVA, effect size, and Post Hoc tests. Findings indicated the effectiveness of the Local Wisdom-based Physics PBL E-module in enhancing both analytical thinking skills and scientific attitudes among students.

Curso introductorio de cristales líquidos I: fases y propiedades estructurales

2024-07-06T02:12:54+00:00

Los cristales líquidos son el prototipo de la llamada materia condensada suave. En términos simples, son “líquidos con estructura” que históricamente han recibido mucho interés tanto por ser fuente de nuevos conceptos y conocimientos en Física, como por tener aplicaciones electroópticas importantes, e. g. en las pantallas de computadoras portátiles y teléfonos celulares. Más recientemente, se ha descubierto que los cristales líquidos podrían aplicarse en la fabricación de metamateriales y en biomedicina, donde son potencialmente útiles en la identificación de tejidos, la repartición controlada de fármacos y la detección de bacterias y virus. No obstante, en México, los cursos sobre cristales líquidos se incluyen en muy pocos programas universitarios de Física y en la mayoría de los casos son optativos. Por ello, es escasa la literatura en español para la enseñanza sobre cristales líquidos. En este artículo discutiremos sobre la Física elemental de los cristales líquidos y las herramientas matemáticas que permiten analizarlos. Principalmente, explicaremos cómo caracterizar analíticamente la simetría y el orden de los cristales líquidos nemáticos uniaxiales estáticos, la fase de cristal líquido más sencilla de todas. Conduciremos esta explicación en términos básicos, apropiados para estudiantes de ciencias o ingenierías a un nivel intermedio de licenciatura, con conocimientos de álgebra lineal y cálculo vectorial, que deseen acercarse por primera vez a este tema. Nuestro objetivo es objetivo es apoyar a la comunidad científica mexicana en la formación de recursos humanos en este campo.

Liquid crystals are the prototype of the so-called Soft Condensed Matter. In simple terms, they are “structured liquids” that historically have received a lot of interest because they help to generate new concepts and knowledge in physics, and possess important electro–optical applications, e.g., in displays of mobile computers and telephones. More recently, it has been discovered that liquid crystals could be applied in the fabrication of metamaterials and in biomedicine where they are potentially useful for tissue identification, controlled drug delivery, and detection of bacteria and viruses. However, in Mexico, liquid crystals courses are included only in a few undergraduate programs on physics, being elective in most of the cases. Therefore, literature for teaching about liquid crystals in Spanish is scarce. In this paper we will discuss about the elementary physics of liquid crystals and the mathematical tools that permit us to analyze them. We will explain, mainly, how to analytically characterize the symmetry and order of static uniaxial nematic liquid crystals, the simplest of all liquid crystal phases. We will conduct this explanation in basic terms, suitable for science and engineering students at intermediate undergraduate level, with knowledge about linear algebra and vector calculus, willing to approach to this subject for the first time. Our goal is to support the Mexican scientific community in preparing human resources in this field.

Una propuesta de preparación para la olimpiada nacional de física basada en el Aprendizaje Basado en Problemas

2024-08-21T01:05:13+00:00

En la Olimpiada de Física, tradicionalmente la preparación y las oportunidades que se les da a los alumnos de cada estado son sumamente diferentes (con base en los resultados históricos de cada estado). En este trabajo se realiza una propuesta que busca reducir (en la manera de lo posible) las diferencias en la preparación, permitiendo así que los estudiantes tengan la oportunidad de participar mejor preparados y poder así obtener mejores resultados. El presente trabajo se centra en la preparación para la prueba experimental de la Olimpiada, para ello, se seleccionó como referencia el modelo Aprendizaje Basado en Problemas, el cual se modificó, agregando y quitando algunos elementos (que se describirán a continuación), el Aprendizaje Basado en Problemas es un modelo educativo que empodera estudiantes en un proceso de enseñanza-aprendizaje autodirigido que busca resolver problemas complejos del mundo real.

In the Physics Olympiad, traditionally the preparation and opportunities given to students in each State is widely diverse (based on the historical performance of each State). In this work, we show, a proposal that seeks to reduce (as much as possible) the differences in preparation, thus allowing the students to have the opportunity of having a better preparation and then improve the chances to obtain better results. The present work focuses on the preparation for the experimental test of the Olympiad, for this the Problem-Based Learning model was selected as a reference, which was modified, adding and removing some elements (that will be described below), the Problem-Based Learning is an educational model that will empower students in a self-directed teaching-learning process that seeks to solve complex real-world problems.

The multiple representations ability of students in linear motion

2024-10-31T20:27:43+00:00

This research aims to reveal students’ ability to analyze the equation of position versus time, so students can describe quantities of motion with multiple representations in linear motion. Subjects included 54 students of XI grade from one of the high schools in Pasuruan and Sumenep Madura. Then three students were interviewed about the difficulties when making representations. The, research instrument was an open-ended test of linear motion with reability 0.707. The test instrument is a question in position versus time, and then students are asked to answer 5 questions by describing the quantities of motion in the representation of tables, mathematical equations, graphs, verbal, and motion diagrams. The results showed that students had difficulties describing the quantities of motion with multiple representations. The most common difficulty is drawing motion diagrams. The study recommended further research using learning-based multiple representations to improve conceptual understanding.

Determination of the coherence length and beat frequency length using a p-emf sensor

2024-11-07T17:31:18+00:00

The coherence of light is essential for understanding interference phenomena, which are pivotal in a wide range of applications. However, due to the technical challenges of conventional methods, quantifying coherence is difficult to achieve in undergraduate optics laboratories. In this work, we present a modification of a method and experimental setup that can enhance the understanding of coherence concepts employing a sensor based on the non-steady-state photo-electromotive force (p-emf) effect. This p-emf sensor generates an electrical current proportional to the square of the interference pattern’s visibility, eliminating the need for image processing and high-quality optical elements, and allowing for real-time measurements. We demonstrated the method by measuring the coherence length of a He-Ne laser and the corresponding length associated with the beat frequency of the laser cavity’s longitudinal modes. This approach is robust, straightforward and simple, making it suitable for implementation in undergraduate optics laboratories.

Numerical solution of partial differential equations using the discrete Fourier transform

2024-11-04T23:19:49+00:00

In this paper, we explain how to use the Fast Fourier Transform (FFT) to solve partial differential equations (PDEs). We start by defining appropriate discrete domains in coordinate and frequency domains. Then describe the main limitation of the method arising from the Sampling Theorem, which defines the critical Nyquist frequency and the aliasing effect. We then define the Fourier Transform (FT) and the FFT in a way that can be implemented in one and more dimensions. Finally, we show how to apply the FFT in the solution of PDEs related to problems involving two spatial dimensions, specifically the Poisson equation, the diffusion equation and the wave equation for elliptic, parabolic and hyperbolic cases, respectively.

Toward student’s scientific literacy in science learning: A systematic literature review and bibliometric analysis

2024-11-14T15:01:35+00:00

One of the main goals of science education is to create a young generation who has adequate scientific literacy skills. This study aims to analyze research trends, implications of empirical research, and review and bibliometric analysis of scientific literacy in science education. The research method used is a systematic literature review and bibliometric analysis with Biblioshiny software. Data were obtained from SCOPUS and Web of Science (WoS) from 2014 to August 2024. The data selection process was carried out using PRISMA, with which 140 documents were obtained. The research trend of scientific literacy in science education shows an increase. Empirical research has been carried out by countries such as the United States, the European Union, the United Kingdom, and Indonesia. Article review in science learning towards scientific literacy has been developed using various methods. Bibliometric analysis shows three clusters of co-occurrences including educational literacy, scientific literacy, and human. The visual representation of the scope of scientific literacy can develop along with the development of science content and context in life. Future research can conduct empirical research that focuses on developing learning strategies and assessments as well as conducting critical review research to optimize research on scientific literacy.

De la teoría al análisis de datos de ondas gravitacionales

2024-12-16T00:56:03+00:00

En este artículo se introduce la teoría y el análisis de datos de ondas gravitacionales con el propósito de replicar, paso por paso, la detección y estimación de parámetros de la primera señal de onda gravitacional reportada por la colaboración LIGO. Para ello se presenta la teoría de Einstein linealizada, el desarrollo analítico de señales de sistemas binarios y las polarizaciones esperadas de una inspiral de objetos compactos. Posteriormente, se introducen las técnicas estadísticas básicas del análisis de estas señales y el método de detección. Finalmente, se analiza el evento GW150914, obtenido de la paquetería PyCBC, se filtra la señal para visualizarla y se realiza la estimación de las masas y la distancia. Con el propósito de facilitar la reproducción de este hito de la física relativista, se incluye el código para filtrar la señal y lograr su visualización y estimación de parámetros.

This article introduces gravitational wave theory and data analysis with the purpose of replicating, step by step, the detection and parameter estimation of the first gravitational wave signal reported by the LIGO collaboration. For this purpose, the linearized Einstein theory and the expected polarizations of a compact object inspiral are presented. Then, the basic statistical techniques for analyzing these signals and the detection method are introduced. Finally, the GW150914 event is analyzed, the signal is filtered for visualization, and the masses and distance are estimated. To facilitate the reproduction of this milestone in relativistic physics, the code for filtering the signal and achieving its visualization and parameter estimation is included.

Tsung-Dao Lee has died, long live parity symmetry breaking!

2024-11-20T17:20:04+00:00

On August 4, 2024, Tsung-Dao Lee, a renowned theoretical physicist of Chinese origin, passed away at the age of 97. His most famous discovery dates back to 1956, when – together with Chen-Ning Yang – he postulated that parity symmetry might be broken by the weak interaction. They suggested experimental tests of this revolutionary idea, which were conducted within one year. The results confirmed the conjecture by Lee and Yang, thus changing a core paradigm of physics.