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All Journal EKSAKTA: Journal of Sciences and Data Analysis Jurnal Penelitian Pendidikan IPA (JPPIPA) INDONESIAN JOURNAL OF APPLIED PHYSICS Jurnal Pengabdian Pada Masyarakat Eksakta : Berkala Ilmiah Bidang MIPA Pelita Eksakta Pillar of Physics Education : Jurnal Berkala Ilmiah Pendidikan Fisika Pillar of Physics: Jurnal Berkala Ilmiah Fisika Journal of Climate Change Society Journal of Experimental and Applied Physics
Letmi Dwiridal
Universitas Negeri Padang
Agriculture, Biological Sciences & Forestry Humanities Astronomy Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Earth & Planetary Sciences Education Electrical & Electronics Engineering Energy Engineering Environmental Science Materials Science & Nanotechnology Mathematics Mechanical Engineering Physics Social Sciences Other

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THE EFFECT OF COOPERATIVE LEARNING MODEL USING PHET SIMULATION ON PHYSICS STUDENT’S ACHIEVEMENT nabila aulia rahma; Ratnawulan Ratnawulan; Letmi Dwiridal; Renol Afrizon
PILLAR OF PHYSICS EDUCATION Vol 16, No 1 (2023)
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/14327171074

Abstract

The purpose of this study was to measure students' academic skills using a group survey model using Phet.. These skills can be acquired by adopting an appropriate learning model in terms of mastery of materials and skills.. A survey was conducted at Senior High School and information was obtained that students' learning results still needed to be higher. Students' learning outcomes can be improved by using learning models and media. The solution that can be done is to apply the GO type cooperative model using PhET simulation. This research is pseudo-experimental, posttest-only design. The population of this study were all XI science classes of Senior high scholl , registered in the 2022/2023 academic year. Sampling was done using a purposive sampling technique, grade XI IPA 1 and grade XI IPA 2  classes were selected as samples. The instruments used were posttest questions for knowledge-skills observables for attitudes and skills-skills, and the research hypothesis was tested using the t-test. Research results using t-test lead to the conclusion that in students' knowledge competency, the value of Tcounts 5,279> Ttable 1,994437. Regarding attitude competency, the value of T is 11,89> Ttable 1,994437. In the skill competency, the value of Tcount is 3,3580> Ttable 1,994437. This shows that the hypothesis is accepted. So, motivating in the form of a posttest can improve the learning outcomes of physics students in Class XI IPA at Senior high school in the 2022/2023 school year.
Analysis of Liquefaction Potential in Sungai Limau District Padang Pariaman Regency Using the Multichannel Analysis of Surface Wave (MASW) Method Angeline Chika Rorensia; - Syafriani; - Hamdi; - Akmam; Letmi Dwiridal
PILLAR OF PHYSICS Vol 16, No 1 (2023)
Publisher : Department of Physics – Universitas Negeri Padang UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/14326171074

Abstract

Sungai Limau is one of the sub-districts in Padang Pariaman Regency which was badly damaged by the earthquake on 30 September 2009. Geologically, the Sungai Limau area is included in the category of cambisol soil types in the form of layers of sand, making it vulnerable to liquefaction due to earthquakes. This research was conducted to analyze the liquefaction potential using the Multichannel Analysis of Surface Wave (MASW) method. The MASW method can produce 2D Vs profiles to describe the structure and types of rock-forming materials at each depth and layer. This method can detect underground surfaces Vs to a depth of 30 meters. Data collection was conducted at Sungai Limau using the sysmatrack-MAE tool with 4 observation tracks. Each measurement uses a distance between geophones of 4 meters. The Vs results from MASW will be compared with the classification of soil types from UBC 1997. The average results of the shear wave velocity at a depth of 30 m (Vs30) in this study are 322.9 m/s for the first track, 303 m/s for the second track, 311 m /s for the third and fourth track. The four tracks fall into the same classification, namely medium soil type (class D). The results of the liquefaction potential analysis using the MASW method show that the first line has a high level of liquefaction potential in the third layer with a value of Vs 337 m/s (class D). The second track has a high level of liquefaction potential in the third layer with a value of Vs 314 m/s (class D). The third track has a fairly high level of liquefaction potential in the second layer with a value of Vs 209 m/s (class D). The fourth track has a high level of liquefaction potential in the second layer with a value of Vs 198 m/s (class D). The fourth and fifth layers on the entire track have no liquefaction potential with Vs ranging from 400-550 m/s (Class C).
Analysis of the Comfort Level of Climate in the Padang Coastal Tourism Area Using the Holiday Climate Index (HCI) Method Randy; Nofi Yendri Sudiar; Ahmad Fauzi; Letmi Dwiridal
Journal of Climate Change Society Vol. 1 No. 1 (2023)
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jccs/Vol1-iss1/3

Abstract

Padang city is one of the regions of Indonesia that has potential in the tourism sector, one of which is beach tourism. The tourism sector is one of the largest sectors and the main mainstay for the economy in various countries, including Indonesia. Countries that rely on the tourism sector must pay attention to several factors that attract tourists, one of which is climate comfort. Climate information is a major factor in choosing a tourist trip. This study aims to analyze the level of climate comfort in the coastal tourism area of Padang City using the Holiday Climate Index (HCI) method. HCI uses climate parameters such as air temperature, humidity, wind speed, rainfall, and cloud cover. HCI calculation data in the form of observation data obtained from the Meteorology Climatology Geophysics Agency (BMKG) station at Minangkabau International Airport and the Teluk Bayur Maritime Meteorology Station from 2011-2020, direct measurement data from August to September, and questionnaires. The results of the HCI analysis show that the city of Padang is comfortable throughout the year, with the HCI value in the range of 58.6-71.6 which is categorized as acceptable to very good. The results obtained through direct measurements also obtained comfortable results throughout the day with HCI values in the range of 70-80. Perceptions of tourists interviewed also stated that overall tourists felt comfortable with the percentage of respondents as much as 74.1%. HCI can be used as a source of information to determine the value of climate comfort in tourist areas.
Thermal Comfort Index Analysis of Padang City Coastal Tour-ism Area Using the Physiological Equivalent Temperature (PET) Method Sadinda Tsania Suhada; Nofi Yendri Sudiar; Hamdi; Letmi Dwiridal
Journal of Climate Change Society Vol. 1 No. 1 (2023)
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jccs/Vol1-iss1/5

Abstract

This study aims to determine the category of comfortable thermal sensation in traveling based on the value of the Physiological Equivalent Temperature (PET) thermal index. The research sites were selected in Padang Beach (PP), Air Manis Beach (PAM) and Nirwana Beach (PN). Calculation of perception of comfort using questionnaire data to visitors. PET calculation data is sourced from the Meteorology, Climatology and Geophysics Agency (BMKG) in 2011-2020 and direct measurement data. The results show that the PET thermal sensation category for the Padang City coastal area throughout the year (2011-2020) is included in the "warm" category for tourism activities. Likewise, direct measurements show the "very hot" category with a PET value of 40.3ºC. However, interviews with visitors showed that the overall comfort condition was “neutral” (62%). This is due to environmental conditions that provide a comfortable effect on visitors. The majority of visitors were interviewed under the auspices. Although the measured air temperature is classified as "high", the effects of trees, walking paths and rest areas make visitors feel comfortable.
Analysis of Extreme Rainfall in Padang City Based on The Influence of MJO and IOD in The Period 1991-2020 Cindy Magriza Putri; Nofi Yendri Sudiar; Hamdi; Letmi Dwiridal
Journal of Experimental and Applied Physics Vol 1 No 2 (2023): September Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v1i2.15

Abstract

Rainfall above normal can be categorized as extreme rainfall. Extreme rainfall can be caused by various factors, such as global, local, and regional factors. Some regional factors that influence rainfall are the Madden Julian Oscillation (MJO) and the Indian Ocean Dipole (IOD). Padang City has high rainfall intensity which can result in extreme rainfall. The lack of adequate disaster mitigation results in flood disasters when extreme rainfall occurs. Therefore, this research aims to determine normal rainfall, extreme rainfall trends and the relationship between the MJO and IOD phenomena with the frequency of extreme rainfall in Padang City. This information is needed for future disaster mitigation planning. The method used is the time series method and statistical correlation test. Based on the results of the analysis, it is known that Padang City is an area with an equatorial rain type, where the highest rainfall occurs in November with a value of 512 mm and the lowest in May with a value of 268 mm. The trend in extreme rainfall tends to decrease with regression coefficient values ​​of 0.0412 and 0.0708. There is a significant relationship between the number of negative IOD events and the frequency of extreme rainfall with a correlation coefficient of 0.483 and 0.403 which indicates a moderate correlation. There is no significant correlation between the number of strong MJO events in Phases 3 and 4 and the frequency of extreme rainfall, with a correlation coefficient of -0.038 – 0.105.
Analysis Of Changes In Seismic Rate (Seismic Rate Change) Based On Seismotektonic Spatial Distribution Of Bengkulu Area Fadhil Ramadhani; Syafriani; Hamdi; Letmi Dwiridal
Journal of Experimental and Applied Physics Vol 1 No 2 (2023): September Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v1i2.17

Abstract

Bengkulu Province has a high level of seismicity with significant earthquakes preceded by the phenomenon of decreased seismic activity (seismic quiescence) which can be seen through observing changes in seismic rate in an area based on the spatial distribution of z values. This study uses data from the USGS website for the period 1925-2021 to study seismic rates changes based on the spatial distribution of z values. In this study there are seven research focus zones, five major earthquake zones 1934 (7.0 SR), 1943 (7.0 SR), 2000 (7.0 SR), 2001 (7.0 SR), 2007 (7.7 SR), as well as two seismic activity zones with coordinates -5.6° to -4° south latitude and 101.6° to 103.4° east longitude and a seismic gap zone with coordinates –4.2° to -2.5° South latitude and 102.6° to 104.5° East longitude. The observation result show that before the earthquake occurred in the period 1925-2021, Before the earthquake, there had been a seismic quiescence phenomena. Four years before 2021, the seismic quiescence phenomena occurs in high seismic activity zones., while the seismic gap area occurs seven years before 2021. Overall, the seismic activity analysis result in Bengkulu province area shows an increase and decrease in seismic activity simultaneously in several different areas. This should be suspected of being the beginning of a significant earthquake in the future.
Microzonation Analysis of Soil Vulnerability Index of Sumani Region As Part of The Sumatra Fault System Using Microtremor: Analisis Mikrozonasi Indeks Kerentanan Tanah Daerah Sumani Sebagai Bagian Dari Sistem Sesar Sumatera Menggunakan Metoda Mikrotremor Lingga Ayunda Pradipta; Syafriani Syafriani; Hamdi Hamdi; Letmi Dwiridal
Journal of Experimental and Applied Physics Vol 1 No 3 (2023): December Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v1i3.30

Abstract

West Sumatra is a province located on the west coast of the island of Sumatra in the middle which has four active fault segments. Nagari Sumani is part of the Sumani Segment line, which makes Nagari Sumani very vulnerable to earthquakes. Efforts are needed too . reduce the impact of the earthquake in Nagari Sumani. This study aims to determine the value of soil vulnerability index (Kg) and soil vulnerability index microzonation (Kg) in Nagari Sumani, specifically Jorong Pinjangek and Jorong Guci, in the area of ​​the Sumani Segment route. The microtremor method of measuring this microtremor can determine the dominant frequency value (f0), amplification factor (A0), and soil susceptibility index value (Kg). Microtremor data was used to obtain the H/V curve at each point of data collection using Geopsy software. Seismic vulnerability index microzonation is carried out using software Surfers 13. The results of this study indicate that the seismic vulnerability index in Nagari Sumani ranges from 3.65 x 10-6 s2/cm to 99.51 x 10-6 s2/cm which has low, medium, to high categories. The results of microzonation of low soil susceptibility index (Kg) are at points 1,2,7, and 8 with a value range of 3.65 x 10-6 s2/cm to 41.02 x 10-6 s2/cm, the medium category is in points 3 and 5 with a value range of 50.02 x 10-6 s2/cm to 54.23 x 10-6 s2/cm, while the high category is at points 4 and 6 with a value range of 63.32 x 10-6 s2/cm to 99.51 x 10-6 s2/cm .
Analysis Of The Relationship Of Rare Earth Elements To Magnetic Minerals In Pumice In The Southern Tip Of Lampung Province Rifqa Hayati; Hamdi Hamdi; Letmi Dwiridal; Harman Amir
Journal of Experimental and Applied Physics Vol 1 No 3 (2023): December Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v1i3.31

Abstract

In advanced clean energy technologies, rare earth elements (REEs) are an important component. The position of rare earth elements in the future is increasingly strategic so it is necessary to strive to be developed sustainably. At the southern tip of Lampung province, rare earth elements are not yet known. The aims of this study were to analyze the magnetic susceptibility value, composition and percentage of rare earth elements, and the relationship of rare earth elements with magnetic mineral concentrations in pumice at the southern tip of Lampung Province. The method employed is rock magnetic method with Bartington Magnetic Susceptibility Meter Type B and X-Ray Fluorescence. Pumice in the southern region of Lampung Province has diverse magnetic susceptibility values, pumice from Bandar Lampung City has the highest magnetic susceptibility value, while the lowest is in South Lampung Regency. This pumice has antiferromagnetic and ferrimagnetic magnetic properties, and was found to have almost no superparamagnetic grains and also found a mixture of superparamagnetic and coarse grains. The composition of rare earth elements contained in pumice at the southern tip of Lampung Province obtained 3 rare earth elements, samples from Bandar Lampung City contained europium, cerium, and yttrium elements and samples from South Lampung Regency contained europium and yttrium elements. Rare earth elements and magnetic mineral concentration have a relationship, the obtained values decrease with increasing percentage of rare earth elements.
Analysis Of The Relationship Of Rare Earth Elements To Magnetic Mineral Concentrations In Pumice Around Sigura-Gura Dian Laila Fitri; Hamdi Hamdi; Ahmad Fauzi; Letmi Dwiridal
Journal of Experimental and Applied Physics Vol 1 No 3 (2023): December Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Rare earth elements are part of one of the strategic minerals and are included in the "critical minerals". Concentrations of rare earth elements are economically precious deposits that can be used as mining commodities. Pumice is the result of volcanic eruptions and it is one of the minerals containing the rare earth elements, one of which is found in Sigura-Gura, North Sumatra. The research aims to determine the composition of rare earth elements, the relationship between rare earth elements and magnetic mineral concentration, and to determine the concentration of magnetic minerals in pumice in Sigura-gura. The method employed is rock magnetic method with Bartington Magnetic Susceptibility Meter Sensor type B (MS2B), and X-Ray Fluorescence (XRF). Results indicated that Sigura-Gura pumice samples, and Sigura-Gura Waterfall have quite varied magnetic mineral concentrations with a range of values from 111,3 x 10-8m3/kg to 349,9 x 10-8m3/kg, with antiferromagnetic magnetic properties and grain types with almost no SP grains. Samples of Sigura-Gura pumice contain elements of Eu, Ce, and Y, while samples from Sigura-Gura Waterfall contain elements of Eu and Y. There is a correlation between the amount of magnetic minerals and rare elements, and the more elements are present in a sample, the lower the value that is produce, and the greater the percentage of elements obtained, the smaller (%) is obtained.
Analysis Of Earthquake Fault Type In 2022 in the Mentawai Region Using Waveform Inversion Method Ika Sri Fahmi; Syafriani Syafriani; Hamdi Hamdi; Letmi Dwiridal
Journal of Experimental and Applied Physics Vol 1 No 3 (2023): December Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v1i3.34

Abstract

Indonesia is a country prone to earthquake disasters, because Indonesia is located in the collision area between plates, and one of the areas in Indonesia where plate movements often occur is Mentawai. Analysis of waveform data on the 2022 earthquake in the Mentawai region was carried out to determine the type of fault. The data used in this research is local seismic data downloaded from webdc.eu. Seismic data was analyzed using waveform inversion method implemented in ISOLA program. In the ISOLA program, data processing is carried out which includes: inputting 3-component seismic data, earthquake info events, selecting stations, green functions, performing inversion, and displaying results in the form of tensor moment values, strike, dip, and rake values. From the data analysis, the moment tensor value is obtained with the range of each component of M11 is -8.348 to -3.673, M22 is 0.710 to -2.037, M33 is 7.639 to 5.710, M31 is 2.050 to 3.761, M32 is 3.484 to -5.672, M12 is -2.751 to 2.455. Then the inversion results obtained in the form of fault parameters, namely strike, dip, and rake for two nodals that will be analyzed to determine the fault plane. Based on the moment tensor value, it is found that the type of earthquake fault in 2022 in Mentawai region is dominated by reverse fault and oblique fault patterns.
Co-Authors - Asrizal - Hamdi Ahmad Fauzi Akmam Akmam Angeline Chika Rorensia Anisa Rahmi Anisa Rahmi Ardilla Nofri Yuwanda Ardilla Nofri Yuwanda Cindy Magriza Putri Dessri Mai Syarif Dian Laila Fitri Dwi Anisa Visgun Dwi Anisa Visgus Eka Fitri Eko Muda Setiawan Elka Fitri Enora Fadhil Ramadhani Fahmi Rahmatia Fajri Syukur Rahmatullah Fandu Alfadilah Fanny Rahmatina Rahim Fatni Mufit Festiyed Gusmita Cahnia Putri Hamdi Hamdi Rifai Harman Amir Hidayati Hidayati Hilmi Rizki Anjani Hufri Hufri Ika Sri Fahmi Ikhsan Buyung Arifin Juliana Dekriani Lingga Ayunda Pradipta Mia Nova Isnia Gara Miftahul Jannah nabila aulia rahma Nadya Fitra Kurnia Najmil Khaira Nofi Yendri Sudiar Putra, Amali Putri Nurhaliza Ramli Ramli Randy Ratnawulan . Renol Afrizon Rifqa Hayati Riza Rahmayuni Riza Rahmayuni Sadinda Tsania Suhada Silvi Yulia Sari Silvia Irani Sugeng Nugroho Syafriani Syafriani Syafriani Syahrul Gunawan Trio Junira Fernando Yenni Darvina Yunita Syafitri Yurnetti Yurnetti Zulhendra Zulhendra