Wahana Fisika最新文献

{"title":"EVOLUSI DINAMIK SUN'S BIRTH CLUSTER DAN PENCARIAN SOLAR SIBLINGS DI BIMASAKTI","authors":"Rendy Darma, M. I. Arifyanto","doi":"10.17509/WAFI.V4I1.15706","DOIUrl":"https://doi.org/10.17509/WAFI.V4I1.15706","url":null,"abstract":"Sebagian besar bintang-bintang di galaksi terbentuk di dalam gugus bintang, baik gugus terbuka maupun gugus bola. Begitu juga dengan Matahari, yang diperkirakan terbentuk pada 4,6 milyar tahun lalu di dalam sebuah gugus terbuka (sun’s birth cluster). Bintang-bintang yang terbentuk bersamaan dengan Matahari di dalam sun’s birth cluster, disebut sebagai solar siblings. Argumen ini didukung oleh penemuan radioisotop berumur pendek dan objek-objek Edgeworth-Kuiper yang memiliki inklinasi dan eksentrisitas tinggi di Tata Surya. Pekerjaan ini bertujuan untuk mempelajari evolusi dinamik sun’s birth cluster selama 4,6 milyar tahun dan mencari keberadaan solar siblings di Bimasakti dalam radius 1 kpc dari Matahari. Simulasi N-benda dilakukan untuk memahami evolusi dinamik sun’s birth cluster dan sebaran solar siblings saat ini dalam pengaruh potensial gravitasi Bimasakti. Sebanyak 2 juta bintang dari katalog GAIA DR2 digunakan untuk mencari solar siblings dalam radius 1 kpc dari Matahari. Hasil dari pekerjaan ini menunjukkan bahwa sun’s birth cluster mengalami kehancuran pada usia kurang dari 1 milyar tahun setelah pembentukannya, akibat adanya gangguan pasang surut Bimasakti yang menyebabkan solar siblings terlepas dari sun’s birth cluster dan menyebar di sekitar orbit Matahari saat ini. Semakin besar jumlah bintang sun’s birth cluster yang dimodelkan, semakin banyak solar siblings yang dapat ditemukan di sekitar Matahari. Analisis kinematika dan fotometri solar siblings menunjukkan setidaknya terdapat 14 hingga 19 kandidat solar siblings pada katalog GAIA DR2 dalam radius 1 kpc dari Matahari.","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122234498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SUATU STUDI PEMODELAN VISKOELASTIK MATERIAL BENANG VIZ 100% WOOL 36 TEX MENGGUNAKAN PENDEKATAN FISIKA","authors":"Valentinus Galih Vidia Putra, Andrian Wijayono, Irwan, Tina Martina, Cahaya Rosyidan","doi":"10.17509/WAFI.V4I1.15500","DOIUrl":"https://doi.org/10.17509/WAFI.V4I1.15500","url":null,"abstract":"Suatu model matematis viskoelastik untuk menentukan besar koefisien viskos serta koefisien elastik suatu benang tekstil telah dikaji pada penelitian ini. Suatu persamaan matematis benang tekstil viz. 100% wool yang memiliki nomor benang 36 tex atau 36 (g/km) telah dirumuskan menggunakan mekanika klasik. Hasil studi memperlihatkan bahwa pemodelan ini dapat digunakan untuk menentukan sifat viskoelastik material berdasarkan sifat stress relaxation.","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116266200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IDENTIFIKASI AKUIFER BERDASARKAN METODE GEOLISTRIK SUSUNAN SCHLUMBERGER DI KECAMATAN PEJAGOAN, KEBUMEN","authors":"Nandian Mareta Hermawan, C. Ansori","doi":"10.17509/WAFI.V4I1.14303","DOIUrl":"https://doi.org/10.17509/WAFI.V4I1.14303","url":null,"abstract":"IDENTIFIKASI AKUIFER BERDASARKAN METODE GEOLISTRIK SUSUNAN SCHLUMBERGER DI KECAMATAN PEJAGOAN, KEBUMEN Nandian Mareta 1*, Chusni Ansori 1 1 Balai Informasi dan Konservasi Kebumian, LIPI, Jl. Kebumen-Karangsambung KM 19, Karangsambung, Kebumen, Jawa Tengah *Penulis Penanggungjawab. E-mail: nand015@lipi.go.id / nandianthea@gmail.com ABSTRAK Identifikasi airtanah menggunakan metode geolistrik susunan Schlumberger telah dilaksanakan di kecamatan Pejagoan, Kebumen. Pejagoan ini merupakan salah satu kecamatan di Kebumen yang cukup cepat perkembangan penduduknya, sehingga kebutuhan sumberdaya air juga meningkat. Setiap musim kemarau resiko kekurangan air selalu terjadi di bagian utara wilayah kecamatan. Penelitian tentang potensi airtanah dalam masih jarang dilakukan, sehingga dilakukanlah kegiatan ini. Susunan Schlumberger merupakan salah satu metode dalam geolistrik untuk mengetahui variasi litologi bawah permukaan melalui perbedaan tahanan jenis batuan. Pengukuran geolistrik dilakukan di 13 lokasi secara sounding, panjang bentangan rata-rata 200-250 meter, dengan kedalaman yang dihasilkan antara 65 meter sampai 140 meter. Berdasarkan nilai tahanan jenis, dapat diinterpretasikan litologi yang dijumpai berupa soil, batu lempung tufaan basah, batupasir tufaan basah, batupasir tufaan kering, batu gamping dan tufa kering. Soil terdapat pada lapisan paling atas, dengan kedalaman 2.000 ohmmeter) diinterpretasikan sebagai tufa kering. Litologi yang dapat berfungsi sebagai akuifer setengah permeabel adalah batulempung tufaan basah dan batupasir tufaan basah.  Batulempung tufaan basah berada pada kedalaman 9 - 16 m, banyak mengalami kekar sehingga dimungkinkan sebagai akuifer dangkal.  Batupasir tufaan basah, pelamparannya lebih luas dapat berfungsi sebagai akuifer pada kedalaman 52 m dengan ketebalan 38 m. Sedangkan sebagai akuifer dangkal terdapat pada kedalaman 4 meter sampai 13 meter. Potensi air tanah pada akuifer dangkal sangat dipengaruhi oleh kondisi musim. Kata Kunci: Geolistrik, susunan Schlumberger, vertical electrical soundin g, akuifer ABSTRACT Groundwater identification using the Schlumberger arrangement geoelectric method has been carried out in Pejagoan sub-district, Kebumen. Pejagoan is one of the sub-districts in Kebumen which has a fairly rapid development of its population, so that water resource needs are also increasing. Every dry season the risk of water shortages always occurs in the northern part of the sub-district. Research on the potential of deep groundwater is still rare, so this activity is carried out. Schlumberger arrangement is one of the geoelectric methods to determine subsurface lithology variations through different types of rock resistance. Geoelectric measurements were carried out in 13 locations by sounding, with an average stretch of 200-250 meters, with a depth of between 65 meters and 140 meters. Based on the type of resistivity value, it can be interpreted as lithology found in soil, wet tuff claystone, wet tuff san","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131189693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"STUDI DISTRIBUSI NEUTRONIK FLUKS PADA REAKTOR NUKLIR SEDERHANA","authors":"Isnaini Nur Islami, Hilma Tismawati, M. N. Subkhi","doi":"10.17509/WAFI.V4I1.15565","DOIUrl":"https://doi.org/10.17509/WAFI.V4I1.15565","url":null,"abstract":"STUDI DISTRIBUSI NEUTRONIK FLUKS PADA REAKTOR NUKLIR SEDERHANA. Materi dasar teknologi reaktor nuklir telah dipelajari pada kuliah fisika reaktor di jurusan fisika fakultas sains dan teknologi Universitas Islam Negeri Bandung. Tujuan utama pada penelitian ini adalah untuk mempelajari sistem perhitungan neutronik berdasarkan persamaan difusi satu dimensi serta menentukan distribusi neutron pada reaktor satu dimensi dengan menggunakan model matematika. Perhitungan ini penting dilakukan untuk menjaga kekritisan reaktor yang didasarkan kepada pengendalian reaksi fisi berantai dalam reaktor, meskipun demikian kegiatan ini tidak dapat dilakukan secara eksperimen di laboratorium. Analisis distribusi fluks neutronik dengan menggunakan Metode numerik untuk persamaan difusi satu grup  dapat diaplikasikan pada reaktor nuklir sederhana. Simulasi reaktor telah dilakukan pada model reaktor satu dimensi menggunakan GUI software dan O ctave .  Perhitungan dilakukan dengan memvariasikan ukuran mesh atau interval dari panjang teras (dx). Grafik distribusi fluks neutron sepanjang diameter teras diperoleh berbentuk parabola terbalik yang dapat dikatakan cukup baik dengan menggunakan tebakan fluks awal 1,25E+05 n/cm 2 .s, dan k-eff 1,025.","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124217573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"STRESS ON SPUR GEAR AND SIMULATION FOR MICRO HYBRID SYSTEMS BY ANSYS WORKBENCH","authors":"A. Islam, Md. Mashrur Islam","doi":"10.22105/JARIE.2019.174397.1083","DOIUrl":"https://doi.org/10.22105/JARIE.2019.174397.1083","url":null,"abstract":"Spur gears are the most well-known kind of gears used in hybrid vehicle’s power transmission. They have straight teeth, and are mounted on parallel shafts. In some cases, many spur gears are utilized without a moment's delay to make huge rigging decreases. In this paper how stress creates on a spur equip under various conditions and conditions and reenactments of a rigging system (two spur gears) is assessed by Ansys workbench. For this static structural and dynamic analysis modeling is utilized. A couple of spurs equip tooth in real life is by and large subjected to two sorts of cyclic stress: contact stress and twisting stress including bowing fatigue. The two stresses may not accomplish their greatest esteems at a similar purpose of contact fatigue. These sorts of failure can be limited by analysis of the issue amid the outline organize and making appropriate tooth surface profile with legitimate assembling strategies.","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114245053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IDENTIFIKASI DAERAH LONGSOR KECAMATAN BAGELEN MENGGUNAKAN METODE MIKROTREMOR","authors":"Gofur Dyah Ayu Gilang Petiwi, Nugroho Budi Wibowo, Denny Darmawan","doi":"10.17509/WAFI.V3I2.12740","DOIUrl":"https://doi.org/10.17509/WAFI.V3I2.12740","url":null,"abstract":"Kecamatan Bagelen merupakan wilayah di sisi barat Pegunungan Menoreh yang mengalami tanah longsor akibat adanya perubahan kondisi geologi menjadi material lepas dan terlongsorkan. Penelitian ini bertujuan untuk mengetahui karakteristik daerah longsor di Kecamatan Bagelen berdasarkan persebaran dan pemodelan parameter mikrotremor, yaitu frekuensi predominan, faktor amplifikasi, ketebalan lapisan sedimen, dan indeks kerentanan seismik. Data mikrotremor diolah dengan metode HVSR dan metode Ellipticity Curve . Hasil penelitian menunjukkan bahwa nilai  daerah longsor adalah 6-8 Hz, nilai  adalah 6-7, dan nilai  adalah 5×10 −4 - 1,1×10 −3 s 2 /m. Ketiga parameter tersebut berada dalam kategori sedang hingga tinggi serta nilai ketebalan sedimen 20-50 m. Bagelen District located in the west of Menoreh Mountain that had landslide caused by deformation. The research aimed to characterize the landslide area in Bagelen District based on microtremor parameters: predominant frequency, amplification factor, sediment layer thickness, and seismic vulnerability index. Data in the form of microtremor signals were then processed by HVSR and ellipticity curve method. The results of the research showed that the value of 𝑓0 ranged from 6 to 8 Hz, the value of 𝐴 ranged from 6 to 7, the value of 𝐻 ranged from 20 to 50 m and the value of 𝐾𝑔 ranged from 5×10−4 - 1,1×10−3 s2/m. The parameter was on medium and high categories with 20 - 50 m sediment layer thickness.","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130438561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"APLIKASI RESERVOIR SATURATION TOOL(RST) LOG PADA CASED HOLE WELL UNTUK EVALUASI KANDUNGAN HIDROKARBON DI CEKUNGAN KUTAI, KALIMANTAN TIMUR","authors":"Priyo Hutomo, Y. Yatini","doi":"10.17509/WAFI.V3I2.12865","DOIUrl":"https://doi.org/10.17509/WAFI.V3I2.12865","url":null,"abstract":"Kondisi fisik sumur yang telah diproduksi sangat sulit untuk dipantau seperti tingkat saturasi fluida akibat dilapisi casing(cased hole). Kombinasi log Density dan Neutron Porosity saja kurang efektif untuk kondisi tersebut. Pengaruh dari cased hole mengurangi sensitivitas log Density dan Neutron Porosity. Reservoir Saturation Tool(RST) log merupakan cased hole log memanfaatkan pulsa neutron untuk pengukuran saturasi dan jenis fluida pada formasi. Log ini sangat efektif untuk evaluasi kandungan fluida setelah diproduksi. Hasil evaluasi tersebut digunakan untuk membedakan lapisan masih atau sudah tidak prospek hidrokarbon. Log ini memanfaatkan log sigma untuk evaluasi fase fluida, carbon oxygen Ratio ( COR ) untuk evaluasi unsur utama fluida terutama rasio karbon terhadap oksigen, dan log saturasi untuk mengidentifikasi persentase lapisan produktif. Umumnya log RST dilakukan di zona-zona produktif.  Hasil  interpretasi  data  log  di  Cekungan  Kutai  menunjukkan  bahwa  terdapat indikasi hidrokarbon di kedalaman 3760 - 3765 feet berupa Gas dan minyak telah berkurang hingga  30%  setelah  diproduksi  dan     pada  kedalaman  3766-3790 feet masih  terdapat kandungan  minyak  sekitar  25%  dan  gas  sekitar  10%  dari  total  kandungan  sebelum diproduksi. K atakunci : Cased Hole , Reservoir Saturation Tool(RST) log, Neutron , Sigma log, Carbon  Oxygen Ratio Log Produced well’s physical properties like fluid saturation is hard to monitored because it has been cased. Combination of density and neutron porosity log isn’t effective in this situation. Effect of casing in a well reduces density and neutron porosity log sensitivity. RST log is a cased hole log using neutron pulse to measure fluid saturation and phase of formation. It is effective for evaluating fluid content of produced well. Evaluation result are used to differentiate prospect or non-prospect hydrocarbon layer after produced. It’s utilize sigma log for evaluating fluid phase, carbon oxygen ratio(COR) for evaluating fluid main content, and saturation log to identify percentage of productive layer. Generally RST log is ran in productive zone. Interpretation result in Kutai Basin showing hydrocarbon indication in depth 3760 – 3765 feet as gas and depleted oil till 30% before, in depth 3766 – 3790 feet around 25 % oil and around 10% gas of total content before produced.","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131817214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PROTOTIPE SISTEM KENDALI SUHU DAN KELEMBABAN KANDANG AYAM BROILER MELALUI BLYNK SERVER BERBASIS ANDROID","authors":"F. Puspasari, Imam Fahrurrozi, T. Satya, Galih Setyawan, M. Fauzan","doi":"10.17509/WAFI.V3I2.14060","DOIUrl":"https://doi.org/10.17509/WAFI.V3I2.14060","url":null,"abstract":"ABSTRAK Ayam broiler merupakan hewan ternak yang memiliki ciri khas pertumbuhan yang cepat dan pertumbuhannya dipengaruhi oleh suhu lingkungan. Kandang merupakan salah satu bagian dari manajemen ternak ayam broiler yang sangat penting untuk diperhatikan, terutama mengenai suhu dan kelembaban. Tujuan penelitian ini adalah membuat prototipe sistem pengukuran besaran fisis berupa pengaturan dan pengukuran  suhu dan kelembaban secara otomatis pada kandang ayam broiler berbasis android untuk memudahkan monitoring. Pada penelitian ini sensor yang digunakan untuk mengukur suhu dan kelembaban dalam sistem monitoring ini adalah sensor DHT11, sedangkan sebagai pengendalinya digunakan Arduino Due. Ketika sensor DHT11 membaca data, maka Arduino akan merekam dan memproses data tersebut. Data pengukuran dapat disimpan dalam bentuk database yang dapat ditampilkan pada halaman aplikasi Blynk  berbasis android. Broiler chickens are livestock that have a characteristic that is fast growth and its growth is influenced by the temperature of the environment. Cage is one part of the management of broiler chickens which is very important, especially regarding temperature and humidity. The purpose of this study was to make a prototype of the physical measurement system in the form of setting and measuring temperature and humidity automatically in an Android-based broiler chicken coop to facilitate monitoring. In this study the sensors used to measure temperature and humidity in the monitoring system are DHT11 sensors, while Arduino Due is used as the controller. When the DHT11 sensor read the data, the Arduino will record and process the data. Measurement data can be stored in the form of a database that can be displayed on Blynk app based on Android. Keywords :  Temperature; Humidity; DHT11; Arduino due; Android","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129460318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PENYIMPANGAN TITIK PUSAT OPTIK LENSA (OC) DENGAN JARAK PUPIL PEMAKAI KACAMATA (PD)","authors":"H. Husna, Fidiawati Bambang, Dian Laela Sari","doi":"10.17509/WAFI.V3I2.13505","DOIUrl":"https://doi.org/10.17509/WAFI.V3I2.13505","url":null,"abstract":"Untuk kenyamanan penglihatan pengguna kacamata, maka diperlukan pemeriksaan penglihatan dan pelaksanaan prosedur dispensing kacamata yang baik dan benar. Pengukuran kesesuaian frame kacamata dengan wajah pemakai merupakan hal yang sangat penting, salah satunya adalah kesesuaian titik pusat optik/ optical centre (OC) lensa dengan pupil distance (PD) pemakai. Penyimpangan OC lensa dengan PD pemakai dapat menyebabkan ketidaknyamanan penglihatan seperti asthenopia, penglihatan kabur, dan sakit kepala. Penelitian ini bertujuan untuk mengetahui ketepatan OC lensa dengan PD pemakai pada kacamata di optik serta menyelidiki penyebab jika terjadi kejadian penyimpangan OC lensa dengan PD pemakai. Penelitian dilakukan dengan metode deskriptif cross sectional dengan melibatkan 100 buah sampel kacamata di Optik Z Tasikmalaya. Data OC lensa diperoleh dari hasil pengukuran lensometer, dan data PD pemakai diperoleh dari lembar ordering. Data-data tersebut direkam dalam lembar observasi dan kemudian dianalisis. Hasil penelitian pada periode April – Juni 2018 diketahui bahwa terdapat 49 buah kacamata (49 %) yang memiliki kesesuaian antara titik OC lensa dengan PD pemakai, dan terdapat 51 buah kacamata (51%) yang mengalami penyimpangan titik OC lensa dengan PD pemakai. Berdasarkan observasi yang dilakukan, dapat diketahui bahwa tingginya persentase penyimpangan titik OC lensa dengan PD pemakai disebabkan oleh kurangnya perhatian petugas optik pada pentingnya proses dispensing seperti tidak dilakukannya pengukuran jarak pupil, pengukuran pada maklon, pembuatan lay out dan pengukuran titik OC lensa. To provide the best vision for spectacle wearers, optometry or practitioners had to carry out visual examination and dispensing procedure thoroughly. Ensuring proper frame of spectacle with the wearer’s facial shape was important parts of dispensing process; one of which is the suitability of lens optical center with the wearers’ pupil distace. Displacement of lens optical center and the wearers’ pupil distance would cause visual discomforts such as asthenopia, blur vision, and headache. This research was aimed to find out the precision of lens optical center and the wearers’ pupil distance of spectacle sold by an optic, and also to investigate the reasons of lens optical center displacement. This research was conducted using descriptive cross sectional methodology, and involved 100 spectacles at Z Optic in Tasikmalaya. The data of lens optical center was obtained from lensometer measurement, while the data of pupil distance was obtained from the optic’s ordering forms. These data were noted in an observation form. The result of data analysis indicates that in the period April-June 2018, there were 49 spectacles (49%) who had precision of lens optical center and pupil distance, and there were 51 spectacles (51%) who had the displacement. Based on the observation, it was found out that high percentage of displacement of lens optical center and the wearer’s pupil distance wa","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"36 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120821906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PENENTUAN SUHU NOL MUTLAK MELALUI PRAKTIKUM TERMODINAMIKA MENGGUNAKAN HUKUM CHARLES","authors":"Defrianto Pratama, Ratu Fenny Muldiani, Kunlestiowati Hadiningrum","doi":"10.17509/wafi.v3i2.13944","DOIUrl":"https://doi.org/10.17509/wafi.v3i2.13944","url":null,"abstract":"Praktikum Hukum Charles dirancang untuk mendapatkan nilai suhu nol mutlak yang menjadi konstanta fundamental di Termodinamika. Hukum Charles menyatakan bahwa pada tekanan tetap dan ruang tertutup, volume gas ideal berbanding lurus terhadap suhu mutlaknya. Hasil praktikum hukum Charles dengan mengunakan metode kuadrat terkecil, menunjukkan bahwa grafik volume terhadap suhu memiliki nilai koefisien determinasi rata-rata (R 2 ) = 0,9986, hal ini menunjukkan bahwa volume dan suhu memiliki hubungan linier yang tinggi. Nilai suhu nol mutlak terbaik diperoleh sebesar -273,45 0 C, sedangkan nilai suhu nol mutlak rata-rata diperoleh sebesar -275,90 0 C dengan ketidakpastian relatif kurang dari 2 %. Kata Kunci : Termodinamika; Hukum Charles; Suhu Nol Mutlak Thermodynamics is one of the basic concepts that must be mastered by engineering students at Politeknik Negeri Bandung, because it’s used to recognize how industrial engineering tools work. Laboratory activities can help students to understand a difficult thermodynamic concept. The purpose of this study was to design and optimize a Charles’s Law experiment device. Charles's Law experiment was designed to determine absolute zero temperature as a fundamental constant in thermodynamics. The experiment results show average of determination coefficient (R2) = 0,9986 on the V-T graph, it’s shows that the volume and temperature have a high linear relationship. The best absolute zero temperature was obtained at -273,45 0 C, while the average absolute zero temperature was obtained at -275,90 0 C with relative error of less than 2%. Keywords :  Thermodynamics; Charles’s Law; Absolute Zero Temperature","PeriodicalId":143376,"journal":{"name":"Wahana Fisika","volume":"2023 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131397850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}