KONSTAN - JURNAL FISIKA DAN PENDIDIKAN FISIKA

Typology and Cognitive Function of Visual Representations in Android-Based Digital Physics Modules: A Content Analysis Study

2026-06-30T14:23:06+00:00

This study aims to identify the typology, functions, and cognitive appropriateness of visual representations in two Android-based digital physics modules — "Fisika 11 Merdeka" (Linear Studio Apps) and "Fisika Gelombang" (Qreatif) — using Levin’s visual function taxonomy and Mayer’s Cognitive Theory of Multimedia Learning (CTML) as analytical frameworks. Through a descriptive qualitative approach with systematic content analysis, data were collected via high-resolution screenshot documentation and structured coding sheets validated by two expert judges. Results reveal that "Fisika 11 Merdeka" is dominated by static visuals serving decorative (±35%), organizational (±25%), and representational (±30%) functions, with no dynamic or interactive representations found. In contrast, "Fisika Gelombang" optimizes Android’s technological affordances through dynamic simulations, interactive features, and application of the signaling principle, with the majority of visuals serving interpretational and transformational functions (±60%). Evaluation of CTML principles shows that both applications effectively apply spatial contiguity; however, both critically violate the coherence principle due to commercial advertisements that generate extraneous cognitive load. This study concludes that digital modules do not automatically guarantee learning quality; developers should shift from mere text digitization toward the optimal use of interactive visual representations free from distracting elements.

Statistical Analysis of Seismicity in West Sumatra (2015–2025) and Aftershock Decay of the 2009 Padang Earthquake Using Gutenberg–Richter and Omori–Utsu Laws

2026-07-04T00:59:14+00:00

Previous studies on seismicity in West Sumatra have generally focused either on frequency–magnitude distribution or aftershock decay separately, with limited integration of updated earthquake catalogs and combined statistical approaches. This study examines the seismicity of West Sumatra using the Gutenberg–Richter (GR) law and the Omori–Utsu aftershock decay model for the 30 September 2009 Padang earthquake. Earthquake catalogs from the United States Geological Survey (USGS) covering the last ten years and the aftershock sequence of the 2009 event were analyzed. The GR law was applied through cumulative frequency–magnitude distributions to estimate the a- and b-values, which represent seismic activity level and magnitude distribution. The Omori–Utsu model was used to determine the decay parameter p and the initial aftershock activity constant K. The results show a strong linear frequency–magnitude relationship with a relatively high b-value, indicating dominant small- to moderate-magnitude earthquakes and high seismicity. Aftershock activity follows the Omori–Utsu decay pattern with a moderately slow decay rate. These results emphasize the influence of subduction zone dynamics and provide important implications for earthquake hazard mitigation in West Sumatra. These results provide updated seismic parameters for West Sumatra, support regional seismic hazard modeling, and contribute to refining empirical parameter estimation for the Sunda subduction setting.

Validity of a Problem-Based Learning Science E-Module Integrated with Ethnophysics to Support Science Process Skills and Critical Thinking Abilities

2026-07-06T01:24:40+00:00

This study aimed to evaluate the validity of a Problem-Based Learning (PBL)-based science e-module integrated with the ethnophysical context of the Perang Ketupat tradition for teaching temperature and heat to support students' science process skills and critical thinking abilities. The study was motivated by the limited integration of Problem-Based Learning, ethnophysics, science process skills, and critical thinking within a single science e-module, as identified through a review of previous studies. This research employed the Research and Development (R&D) method using the Four-D (4D) model, consisting of the Define, Design, Develop, and Disseminate stages, but was limited to the Develop stage focusing on expert validation. The developed instructional package included the Learning Objectives Flow, teaching module, science e-module, Student Worksheets, science process skills assessment instrument, and critical thinking assessment instrument. Product validation was conducted by five purposively selected experts representing science and physics content, instructional design and Problem-Based Learning, ethnoscience, educational assessment, and language. The validation covered content, presentation, and language aspects and was analyzed using Aiken's V coefficient. The results showed that all developed products achieved valid criteria, with Aiken's V values of 0.93 for the ATP, 0.92 for the teaching module, 0.91 for the science e-module, 0.89 for the LKPD, 0.88 for the science process skills assessment instrument, and 0.89 for the critical thinking assessment instrument. These findings indicate that the developed instructional materials satisfy the required quality standards (valid) and are appropriate for subsequent practicality and effectiveness testing before wider classroom implementation.

Fabrication and Characterization of Eggshell-Derived Nano-CaO Thin Films as Anti-Reflective Coatings: Morphological and Optical Properties

2026-07-06T02:35:22+00:00

Light reflection from glass surfaces reduces the amount of solar radiation transmitted into photovoltaic devices, making transparent thin-film coatings an important approach for improving optical transmission. This study investigated the preparation of calcium oxide (CaO) thin films derived from waste chicken eggshells through a simple and sustainable synthesis route. Eggshell powders were calcined at temperatures ranging from 800 to 1100°C, and the resulting CaO was deposited onto glass substrates by spin coating using five precursor concentrations, followed by post-annealing at 300°C. FTIR and XRD analyses confirmed the gradual decomposition of CaCO₃ into crystalline CaO with increasing calcination temperature. The sample calcined at 1100°C exhibited higher crystallinity (80.86%) and a larger crystallite size (19.24 nm) than that calcined at 1000°C. SEM observations indicated that post-annealing reduced the film thickness and produced a more uniform surface morphology. UV–Vis measurements showed that the 0,05 M precursor concentration and has the average thickness of 18,92 nm yielded the highest optical transmittance. The thin film prepared from CaO calcined at 1100°C and post-annealed at 300°C achieved a maximum transmittance of approximately 88% in the visible region (400–900 nm), which was higher than that of the uncoated glass substrate (85%). These results indicate that thermal treatment and precursor concentration significantly influence the structural and optical properties of eggshell-derived CaO thin films, highlighting their potential as transparent coating materials for photovoltaic glass

Synchronization in Coupled Duffing Oscillators: Numerical Exploration using Exponential Time Differencing

2026-07-06T02:57:27+00:00

The regularity that emerges from the interaction between irregular components is one of the fundamental questions in nonlinear physics. In this study, we examine how two externally driven, coupled Duffing oscillators can achieve synchronization. To analyze the dynamics of this system, we use the second-order Exponential Time Differencing (ETD2) numerical method, which allows us to comprehensively map the parameter space by varying the coupling strength () and the driving force amplitude (). The results show that the synchronization process does not occur simply. The process only appears in a certain synchronization window at weak coupling (). Within this region, the most prominent behavior is Phase Synchronized Chaos, where both oscillators achieve perfect phase locking (Synchronization Index ), but their amplitudes remain chaotic and uncorrelated. We also find that the system is multistable, capable of exhibiting several different final states simultaneously. The boundaries between these basins of attraction are highly complex and exhibit fractal patterns, indicating extreme sensitivity to initial conditions. In other words, even if the system parameters remain constant, the final outcome remains difficult to predict. Overall, these findings provide a comprehensive picture of the dynamics of two coupled Duffing oscillators. The results highlight the balance between external driving forces, coupling strength, and intrinsic chaos that forms the basis for directed synchronization.

Epistemological Beliefs About Physics: A Comparison Between Physics and Biology Education Students

2026-07-17T11:20:59+00:00

Epistemological beliefs play an important role in physics learning. This study compared epistemological beliefs about physics between Physics Education and Biology Education students after completing the required introductory physics course. A quantitative cross-sectional comparative survey design was employed involving all students from both programs at a single teacher education institution (N = 47, 20 Physics Education and 27 Biology Education students), predominantly of female students (80.9%). The Indonesian version of the Colorado Learning Attitudes about Science Survey (CLASS) was used to measure overall and categories of epistemological beliefs. Data were analyzed using descriptive statistics and the Mann–Whitney U test, with rank-biserial correlation reported as the effect size. Physics Education students demonstrated higher favorable CLASS scores than Biology Education students overall and across all categories. Significant differences were found for the overall CLASS score (), Personal Interest (), Conceptual Connections (), and Applied Conceptual Understanding (), with the largest effect observed in Conceptual Connections. Nevertheless, both groups showed relatively low favorable scores in Applied Conceptual Understanding and Problem-Solving Sophistication, indicating shared challenges in transferring conceptual knowledge and solving unfamiliar physics problems. These findings suggest that disciplinary orientation is associated with differences in epistemological beliefs about physics. However, because the study employed a cross-sectional design without baseline measurements, causal interpretations should be made with caution. The results highlight the need for introductory physics instruction that more effectively supports conceptual integration, knowledge transfer, and meaningful disciplinary contexts, particularly for students outside physics-related programs.

Science Kit-Assisted Problem-Based Learning: Its Impact on Students' Problem-Solving Skills

2026-07-19T08:12:30+00:00

This study aimed to determine the difference in problem-solving skills between students who learned using the Problem-Based Learning model assisted by a Science Kit and students who learned using a conventional learning model. This research was a quantitative study employing a non-randomized quasi-experimental design, in which the sample was selected using a purposive sampling technique. The study was conducted at SMP N 1 Kejajar, with the research subjects consisting of Class VIII A as the experimental class (25 students) and Class VIII D as the control class (24 students). Data were collected through observation, tests, documentation, and questionnaires. The research instruments used were a problem-solving skills test and a student perception questionnaire. Data were analysed using validity and reliability tests, normality and homogeneity tests, an independent t-test for hypothesis testing, and an N-Gain test to measure the improvement in problem-solving skills. The results showed that, prior to the implementation of the Science Kit-assisted Problem Based Learning model, the learning process was still teacher-cantered, causing students to be relatively passive. After the model was implemented, students became more active in discussions, conducting experiments, and solving the given problems. The analysis revealed a significant difference between the experimental and control classes, as indicated by an independent t-test value of 0.746 and a calculated significance value of 0.000, which is smaller than 0.05. The implementation of the Science Kit-assisted Problem-Based Learning model was also able to improve students' problem-solving skills, as shown by the N-Gain calculation for the experimental class of 0.761, categorized as high.

Psychometric Analysis of Physics Motivation Questionnaire Using the Rasch Model in Muhammadiyah Upper Secondary Schools

2026-08-07T00:13:45+00:00

Motivation to learn is a key factor in the success of physics learning, which requires conceptual understanding and higher-order thinking skills. This study aims to examine the psychometric characteristics of the Physics Motivation Questionnaire (PMQ) among students at Muhammadiyah high schools using the Rasch model. The study participants consisted of 256 students from Muhammadiyah high schools and Muhammadiyah vocational high schools in Yogyakarta. The instrument used was the Physics Motivation Questionnaire (PMQ). Data were analyzed using the Rating Scale Model (RSM) via Winsteps software version 4.6.1. The results showed a person reliability coefficient of 0.90 and an item reliability coefficient of 0.93. A person separation coefficient of 2.98 indicates that the instrument is capable of distinguishing between students’ motivation levels. All items met the criteria for fit with the Rasch model. The PMQ also satisfied the assumption of unidimensionality, with 49.1% of the raw variance explained by the Rasch measures. Furthermore, the Wright Map indicated that students’ ability levels tended to be higher than the difficulty levels of the items. Overall, the PMQ demonstrated high reliability and good fit with the Rasch model in the context of Muhammadiyah high school students. The findings suggest that the PMQ may serve as a useful tool for assessing physics learning motivation among students in Muhammadiyah upper secondary schools. However, further studies examining measurement invariance across Muhammadiyah senior high schools and vocational high schools are needed before broader application across different school types.

The Sun's Influence on Extreme Weather: A Study of Solar Declination and Sunlight Intensity on Rainfall Extremes in West Sumatra, July–December 2025

2026-08-07T00:56:09+00:00

West Sumatra is one of the regions in Indonesia that is vulnerable to extreme rains that often trigger hydrometeorological disasters, such as floods and flash floods. These incidents have an impact on infrastructure damage, disruption of socio-economic activities, and increased risks to public safety. This study aims to analyze the relationship between solar declination, light intensity, and extreme rainfall events in West Sumatra during July–December 2025. The study used 184 daily data points. Rainfall data were obtained from the West Sumatra Climatology Station, Teluk Bayur Maritime Meteorological Station, and Minangkabau Padang Pariaman Class II Meteorological Station. Light intensity data were obtained from the Class II Minangkabau Padang Pariaman Meteorological Station, while solar declination data were sourced from the National Oceanic and Atmospheric Administration (NOAA). The analysis was carried out using descriptive statistics, graphical visualization, spatial mapping with Surfer software, and Spearman correlation tests. The results show that the flash flood in East Malalak (Agam) on November 26, 2025 occurred when the Sun declinated around −21.3°, the intensity of light ranged from (160,000–180,000)W/m², and rainfall reached (200–220)mm. On 27–28 November 2025, light intensity decreased to (40,000–50,000)W/m², while rainfall increased to (430–500)mm and flooding extended to some areas in Agam, Padang, and Padang Panjang. The results of the Spearman test show that light intensity has a stronger negative relationship with precipitation compared to the declination of the Sun (ρ = −0.428), so it has the potential to be a supporting parameter in monitoring atmospheric conditions when combined with other meteorological parameters. This study is limited to the use of light intensity data from a single observation station and correlation analysis that only shows statistical relationships, so further research with multi-station data and more diverse atmospheric variables is needed to gain a more comprehensive understanding.

Forest and Land Fire Susceptibility Mapping Using Kernel Density and Weighted Overlay Approaches in West Sumatra, 2021–2025

2026-08-25T15:24:38+00:00

Forest and land fires are a recurring environmental disaster in Indonesia. Fire occurrence is influenced by various factors, including hotspot density, rainfall, and land cover. West Sumatra is classified as a region prone to forest and land fires, with characteristics that differ between areas. Therefore, susceptibility mapping is very important to support more effective mitigation efforts. This study aims to analyze the spatial distribution of hotspot density using the Kernel Density method and to develop a forest and land fire susceptibility index through the integration of hotspot density, rainfall, and land cover parameters using the Weighted Overlay method in a Geographic Information System (GIS). The data used include hotspots for the 2021–2025 period from NASA FIRMS, rainfall for the 2021–2025 period from CHIRPS, and 2024 land cover from Earthdata. The analysis was carried out at a spatial resolution of approximately 500 m using the Natural Breaks (Jenks) classification. Parameter weighting refers to previous research in Riau Province, with weights of 67.5% for hotspots, 25.7% for land cover, and 6.8% for rainfall. The results show that the highest hotspot density is concentrated in Pesisir Selatan Regency, while Dharmasraya and Pasaman Barat Regencies fall into the medium category. The resulting susceptibility map shows that Pesisir Selatan Regency falls into the very high class, with an index value of 3.2811–4.4760, while the Mentawai Islands fall into the very low class, with an index value of 0.9330–1.2942. Validation using 2024 burned area data shows that approximately 80.40% of the burned area falls within the high and very high susceptibility classes, indicating that the resulting susceptibility map has a fairly good spatial correspondence with actual fire occurrence. The results of this study can be used as supporting information for forest and land fire mitigation efforts in West Sumatra.