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Abstrak :
An unpolarized light beam will change to a linear polarized beam by using a polarizing filter. In turn the linear polarized beam can be rotated in an active medium such as glass if a magnetic field exists. This phenomenon, which is known as Faraday effect, is there for can used as a current sensor. In this experiment, the current to be measured was flowed in Helmohltz coils where a homogeneous magnetic field was generated. Bismuth and Flumbo alloys were used as glass medium. An analyzer detected the linear polarized beam came from the glass. The analyzer was adjustable and has a capability to detect a light signal up to 1 mill radian per degree. The values of the rotation of the polarized light beams in the active medium were determined by Verdet's constant. The characteristics of the glasses were represented by plotted curves of rotation angle versus the wavelengths of the light beam, which shows parabolic form. The sensing current by Faraday effect shows a linear feature of rotation angle with respects to the current value, as predicted by the theory. The result also shows that the glass of Bismuth alloy is more sensitive than the Plumbo alloy.

Abstrak :
Michael Faraday (1791?1867) was one of the most important men of science in nineteenth century Britain. His discoveries of electro-magnetic rotations (1821) and electro-magnetic induction (1831) laid the foundations of the modern electrical industry. His discovery of the magneto-optical effect and diamagnetism (1845) led him to formulate the field theory of electro-magnetism, which forms one of the cornerstones of modern physics. These and a whole host of other fundamental discoveries in physics and chemistry, together with his lecturing at the Royal Institution, his work for the state (including Trinity House), his religious beliefs and his lack of mathematical ability, make Faraday one of the most fascinating scientific figures ever. All these aspects of his life and work and others, such as his illnesses, are reflected in his correspondence. This volume, in which just over 70 per cent of the 841 letters are previously unpublished, covers the latter half of the 1850s and most of 1860. Topics include: Faraday's work on regelation, the transmission of light through gold and his attempts to bring gravity into his general scheme of forces; the offer by Queen Victoria - and Faraday's acceptance - of a 'grace and favour' house at Hampton Court; his advice to Trinity House, the Board of Trade and the Royal Commission on lighthouses; his investigation of the deterioration of the stonework of the relatively new Houses of Parliament; the conservation issues surrounding the National Gallery's pictures; and his appointment by Emperor Napoleon III to be a Commander of the Legion of Honour.

Abstrak :
Penelitian ini bertujuan untuk merancang dan membuat sistem rotasi Faraday sebagai alat karakterisasi sifat Magneto-Optik minyak nabati. Besaran yang diukur adalah intensitas cahaya, besar medan magnet, dan perubahan sudut bidang getar polarisasi. Pengukuran intensitas cahaya dilakukan menggunakan BH1750, pengukuran medan magnet dilakukan menggunakan Gaussmeter. Perubahan sudut bidang getar polarisasi dilakukan oleh stepper motor yang menggerakkan lensa analisator yang sudah dipasang gear. Sumber cahaya yang digunakan adalah laser RGB dengan daya 300 mW. Pengambilan data dilakukan dengan kondisi awal sudut antara lensa Polarisator dan lensa Analisator sebesar 45º. Konstanta Verdet untuk minyak jagung dengan sumber cahaya merah adalah 0,37 mT/m. Konstanta Verdet untuk minyak jagung dengan sumber cahaya hijau adalah 0,55 mT/m. Untuk sumber cahaya biru, nilai konstanta Verdet yang didapatkan adalah 0,73 mT/m. ......This research aims to design and create Faraday’s rotation system as a tool to characterize the Magneto-Optic properties of vegetable oils. The measured magnitude is the intensity of light, the magnitude of the magnetic field, and the change in the rotation angle of polarization. Measurement of light intensity was carried out using BH1750, magnetic field measurement was carried out using Gaussmeter. Changes in the rotation angle of polarization are made by the stepper motor which drives the lens of the analyzer which has been geared. The light source used is an RGB laser with a power of 300 mW. Data is collected by the initial condition of the angle between polarizer lens and analyzer lens at 45º. The Verdet constant for corn oil with a red light source is 0.37 mT/m. The Verdet constant for corn oil with green light source is 0.55 mT/m. For blue light source, the Verdet constant value that obtained is 0.73 mT/m

Abstrak :
ABSTRAK
Pada penelitian ini dilakukan pengujian pada minyak nabati dengan menggunakan metode rotasi Faraday. Rotasi Faraday adalah proses terputarnya bidang getar cahaya yang melewati suatu bahan, karena dipaparkan medan magnet B. Bahan minyak nabati akan memutar sudut bidang getar cahaya terpolarisasi linear, sehingga terdapat perubahan sudut antara polarisator dan analisator. Pengukuran dilakukan dengan memberikan perbedaan sudut antara polarisator dan analisator sebesar 45, hal ini dilakukan untuk mendapatkan perubahan intensitas yang maksimal, sehingga perubahan sudut putar analisator dapat diketahui. Pada penelitian ini minyak nabati yang digunakan memiliki beberapa kondisi berbeda. Pada penelitian ini sistem instumentasi rotasi Faraday yang digunakan memiliki medan magnet sebesar 0 mT hingga 159.63 mT dan memiliki 3 panjang gelombang yaitu merah=625 nm, hijau=520 nm, dan biru=467.5 nm. Hasil dari penelitian mendapatkan nilai konstanta Verdet minyak jagung pada panjang gelombang merah=0.62062 mT/m, panjang gelombang hijau=0.52888 mT/m, panjang gelombang biru=0.34028 mT/m. Nilai konstanta Verdet minyak bunga matahari pada panjang gelombang merah=0.2791mT/m, panjang gelombang hijau=0.6612mT/m, panjang gelombang biru=0.64677mT/m. Nilai konstanta Verdet minyak kedelai pada panjang gelombang merah=0.18147 mT/m, panjang gelombang hijau=0.42724 mT/m, panjang gelombang biru=0.71146 mT/m. Minyak yang telah dipanaskan mengalami perubahan sudut yang semakin positif dengan perubahan gradien yang tidak terlalu signifikan untuk setiap panjang gelombang.

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ABSTRACT
In this experiment vegetable oil has been examined by using principles of Faraday Rotation. Faraday Rotation is a phenomenon that causes the rotation of the plane of polarization when passing through a material after being exposed by magnet field B. The material, vegetable oil, will rotate the angle of plane of polarization to be linier, so that there will be angle difference between the polarizer and analyzer. The measurement is done by giving 450 degrees angle difference between the polarizer and the analyzer, this is done to get maximum intensity hence turning angle of the analizer can be obtained. This experiment uses vegetable oil of various conditions. The magnetic field in the faraday rotation instrumentation used range from 0 mT to 159.63 mT with 3 wavelengths of red=625 nm, green=520 nm, and blue=467.5 nm. The Verdet constant of corn oil for red, green, and blue wavelength are 0.62062 mT/m, 0.52888 mT/m, and 0.34028 mT respectively. While the Verdet constant of sunflower oil are 0.2791mT/m, 0.6612mT/m, 0.64677mT/m respectively. On the other hand the Verdet constant of soybean oil are 0.18147 mT/m, 0.42724 mT/m, 0.71146 mT/m respectively. The oil which is heated has angle difference that become more positive and change of gradient that is insignificant for every wavelength.

Abstrak :
Telah dilakukan suatu penelitian tentang penggunaan serat optik sebagai transduser arus listrik. Efek faraday mendasari perubahan intensitas cahaya yang melewati medan magnet. Berkas laserHe-Ne sebagai pembawa sinyal dilewatkan serat optik. Keluaran laser He-Ne dari serat optik mengenai prisma wollaston dan dipecah menjadi l'x dan Ily. Sensivitas sistem transduser ini tergantung pada intensitas I'„ dan I'y. Hasil penelitian menunjukkan korelasi linear antara sensivitas dan arus listrik masukan sampai 240A

Abstrak :
Pada penelitian ini medan magnet akan ditingkatkan untuk mendapatkan konstanta verdet yang bervariasi Kumparan dengan diameter 2 mm dan hambatan 1,5 Ohm dirancang untuk menghasilkan medan magnet kuat hingga mencapai 500 mT. Kumparan akan dilewatkan arus maksimum 20 A dan tegangan maksimum 30 V. Namun kumparan 2 mm yang dilewati arus sebesar 20 A akan menimbulkan panas berlebih yang mengganggu kestabilan besar medan magnet yang dihasilkan sehingga diperlukan penambahan sebuah sistem pendingin menggunakan blok air yang ditempelkan pada inti magnet dan kumparan. Apabila medan magnet kuat memengaruhi material mengneto-optik (MOE) fase cair yang dilewatkan cahaya maka disebut sebagai metode rotasi faraday. Metode rotasi faraday digunakan untuk mencari besar konstanta verdet. Konstanta verdet merupakan representasi karakteristik material magneto-optik (MOE) fase cair. Pada penelitian ini untuk mendapatkan nilai konstanta verdet, nilai yang diukur adalah besar medan magnet, besar sudut cahaya yang terpolarisasi, dan intensitas cahaya. Menggunakan cahaya laser merah berbentuk titik dengan panjang gelombang 650 nm dengan intensitas cahaya maksimum sebesar 54612 lux. Perubahan sudut dilakukan menggunakan gir yang terhubung degan stteper motor dan sistem analisator. Pengambilan data menggunakan teknik polarisasi yang terpengaruh oleh medan magnet eksternal. Nilai medan magnet yang terukur oleh teslameter dengan variasi antara -250—250 mT. Sudut rotasi faraday diperoleh dari selisih besar sudut polarisator dan analisator dengan selisih sudut mula-mula sebesar 45°. Cahaya yang melewati polarisator dan analisator akan terdeteksi oleh sensor cahaya BH1750. Hasil penelitian ini akan menunjukkan besar konstanta verdet dari setiap material magneto-optik (MOE) fase cair. ......In this research, the magnetic field will be increased to obtain a variable verdet constant. The coil with a diameter of 2 mm and a resistance of 1.5 Ohm is designed to produce a strong magnetic field up to 500 mT. The coil will pass a maximum current of 20 A and a maximum voltage of 30 V. However, a 2 mm coil that is passed by a current of 20 A will cause excessive heat which disrupts the stability of the large magnetic field produced, so it is necessary to add a cooling system using a water block attached to the magnetic core and coil. If a strong magnetic field affects the magneto-optic element (MOE) that is passed by light, it is called the Faraday rotation method. Faraday rotation method is used to find the verdet constant. The verdet constant is a representation of the characteristics of the liquid phase magneto-optic element (MOE). In this research to obtain the value of the verdet constant, the measured values are the magnitude of the magnetic field, the angle of polarized light, and the intensity of light. Using red laser light in the form of a point with a wavelength of 650 nm with a maximum light intensity of 54612 lux. Angle changes are carried out using gears connected to the stepper motor and analyzer system. Data retrieval using a polarization technique that is affected by an external magnetic field. The value of the magnetic field measured by the teslameter varies between -250—250 mT. Faraday rotation angle is obtained from the large difference between the polarizer and the analyzer angle with the initial angle difference of 45°. Light that passes through the polarizer and analyzer will be detected by the BH1750 light sensor. The results of this study will show the magnitude of the verdet constant of each liquid phase magneto-optic element (MOE).

Abstrak :
Penelitian ini bertujuan untuk meningkatkan kinerja sistem Rotasi Faraday sebagai alat karakterisasi sifat Magneto-Optik fasa cair. Peningkatan yang dilakukan adalah memperbesar medan magnet yang dihasilkan dan intensitas cahaya maksimum yang dihasilkan lebih besar. Nilai yang diukur adalah intensitas cahaya, perubahan besar sudut bidang getar cahaya terpolarisasi, dan besar medan magnet. Pengukuran intensitas cahaya menggunakan sensor cahaya BH1750, perubahan sudut bidang getar terpolarisasi linear menggunakan stepper motor untuk menggerakan lensa Analisator yang sudah dipasang gear, dan medan magnet menggunakan Teslameter. Sumber cahaya yang digunakan adalah laser red dot dengan panjang gelombang 650 nm. Nilai intensitas cahaya maksimum yang dihasilkan sebesar 54612 lux. Pengambilan data dilakukan dengan mengatur posisi awal sudut antara Polarisator dan Analisator sebesar 45º, ini dilakukan untuk mendapatkan intensitas cahaya yang maksimal sehingga perubahan sudut bidang getar terpolarisasi dapat diketahui. Perubahan sudut bidang getar cahaya dipengaruhi oleh besar medan magnet, konstanta verdet, dan panjang sampel. Besar medan magnet yang dihasilkan sebesar 144,09 mT dan panjang sampel yang digunakan sebesar 0,008 m. Sampel yang digunakan adalah minyak nabati yang bersumber dari jagung, bunga matahari, dan zaitun. Konstanta Verdet untuk masing-masing sampel minyak nabati yang bersumber dari jagung, bunga matahari, dan zaitun adalah 0,06349 mT/m; 0,06971 mT/m; dan 0,03434 mT/m. ......This research objective is to improving the performance of Faraday Rotation system as instrument of characterization Magneto-Optical in liquid phase. The improvement there is the resulting magnetic field can be increased and the light intensity measured will be maximum. The values that measured were the light intensity, the change in the angle of the plane of the pulsed light, and the magnitude of the magnetic field. To measure light intensity using sensor BH1750, measuring variance in the angle of the linear polarized vibrating field it will using a stepper motor to move the analyzer lens that has been set on a gear, and measuring the magnetic field value using a Teslameter. The light source used a red dot laser with a wavelength of 650 nm. The maximum light intensity sensor value that can be detected is 54612 lux. Data retrieval is done by adjusting the initial position angle between the Polarizer and the Analyzer lens at 45º, this is to get the maximum number of light intensity so that the change in the angle of the polarized vibratory plane can be known. Variances in the angle of the plane of linear polarized light are influenced by there are the magnitude of the magnetic field, the Verdet constant, and the length of the sample. The magnitude result of the magnetic field is 144.09 mT with sample length is 0.008 m. The samples used were vegetable oils from corn, sunflower, and olive. The Verdet constant for corn oil, sunflower oil, and olive oil was 0.06349 mT/m; 0.06971 mT/m; and 0.03434 mT/m, respectively.