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Aplikasi Portable Brix Meter untuk Pengukuran Indeks Bias

BERKALA FISIKA Vol 13, No 4 (2010): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

Measurement of concentration of sucrose (C12H22O11) solution using Portable Brix Meter was analized to determine its refractive index using Abbe refractometer. The materials used are sucrose solution with a concentration of 5%, 10%, 15%, 20%, 25%, 30%, 35% and 40%, and samples fruits of pear, watermelon, orange, apple and melon and others. The concentration of sucrose solution is proportional to the refractive index. The increase of concentration of sucrose solution will increase the refractive index. Correlation between the concentration of sucrose solution with refractive index is expressed by the equation Refractive index of sucrose solution can be determined from its concentration. Keywords:  sucrose solution, concentration, refractive index, portable brix meter

Konduktivitas Listrik Pulp Kakao dengan Fermentasi dan Pengenceran

BERKALA FISIKA Vol 12, No 3 (2009): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

Relation between hydrogen ion exponent (acidity) cacao pulp with energy pass electrics (conductivity) checked to know how ability of cacao pulp at various level of hydrogen ion exponents in sending electrics and also how relation between cacaoes pulps hydrogen ion exponents ably energies pass the electrics.Research done by two treatment that is prose process and fermentation of thinning of cacao pulp. Its way beforehand look for resistivity value (ρ) from cacao pulp. From the resistivity value obtained by conductivity value (σ) cacao pulp. If connected between cacaoes pulps hydrogen ion exponents with energies pass the electrics out of two the treatment, the result is progressively low degree of acidity of cacao pulp, energy pass the electrics is progressively decline.Relation between hydrogen ion exponent with electrics conductivity at cacao pulp at fermentation process yield equation = 2,84782 + 1,01789 e [-(x-2,5)/0,626)] and at thinning process yield equation σ = 3,13506 + 0,46513 e [-(x-2,5)/0,20194). On file energy at cacao pulp is known that longer ammeter galvanometer network is attached smaller the electric current so that the energy still be small.

Rancang Bangun Sistem Pengaturan Suhu Ruang Inkubator Bayi Berbasis Microcontroller AT89S51

BERKALA FISIKA Vol 12, No 2 (2009): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

A room temperature adjustment system for infant incubator has created using electrical sources phase controlling. This device used  to create environment temperature which is normal and stabile, as in mother’s uterus. The main component of room temperature of infant incubator adjustment which uses electrical sources phase controlling is 100 watt fluorescent hot source, temperature sensor LM 35, ADC 0804, microcontroller AT89S51, DAC 0808, Op-Amp LM 741, Phase detector (IC TCA 785), optical isolator (optocoupler), SCR, Pulse transformator, Coding 74LS47 and seven segment display. The temperature sensor, LM 35, perform data acquisition to room temperature of infant incubator. Furthermore, it strengthened and transformed by ADC 0804 to be digital data and read by microcontroller AT89S51. Reading value compared to accepted value, reading difference use for remove phase activator IC TCA 785 through DAC 0808. IC TCA as phase adjuster through trigger SCR TIC 106, it used to obtain temperature variation in heater lamp. The result is setting poin value with reading value have been as according with extinct indicator of lamp at infant incubator room.   Keywords: infant incubator, temperature, phase control, microcontroller.

Aplikasi Transduser Ultrasonik Jenis Immersion Transducer Untuk Karakteristik Media Cair Dan Pengukuran Tingkat Kekasaran Permukaan Beton

BERKALA FISIKA Vol 12, No 4 (2009): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

Research of the application of ultrasonics for liquid medium characteristic and measurement of level of surface roughness of concrete have been done using immersion transducer. This purpose of research is to know characteristic some dilutions based on the atanuasi coefficients and measure surface roughness of concretes based on time of flight. In this research applied by ultrasonic transducer with frequency of 1 MHz.  At attenuation method, awakened ultrasonic signal through pulse generator and connected at transmitter transducer. Ultrasonic wave which transmitted through liquid medium will experience received finite attenuation of receiver. Media liquid which applied is oil and cooking oil. At method time-of-flight, measurement done with object scan which turned around counted 200 rotation apply motor stepper. Object which applied as component of test that is concrete. Reason of selec,choose it this specimen is to minimize attenuation so that will enlarge the bound. Transducer will transmit modulation to object through modulation transmiter and receiver. Result from scanner is presented at CRO ( Cathode Ray Oscilosco). Research result to liquid medium sample showing existence of tendency of increase of attenuation value for ex-oil- and ex-cooking oil if each compared with oil was new and new cooking oil. From measurement of level of surface roughness, obtained by is surface roughness average yield of  concrete A ( Radium of a minimum of 10%, and Ra maximum 16%), and concrete B ( Radium of a minimum of 8%, and Ra maximum 17%). This research result give hope that this method can be developed for inspection innoxious at solid and liquid medium.   keyword : Ultrasonic, attenuation coefficient, level of crudity, Time of Flight

Pengukuran Nilai  dan  Larutan Gliserin Terimbas pada Frekuensi PLN

BERKALA FISIKA Vol 10, No 4 (2007): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

The magnetooptical specific rotary power h and frequence specific rotary power z have been measured in the glycerine through the interaction between external magnetic field modulated at 50-60 Hz and modulated laser light at the wavelength of 632,8 nm and 532 nm. The sample induced by the magnetic field that has the maximum value of 170 mT. The source of light of 632,8 nm and 532 nm is modulated between 30 Hz and 100 Hz. The result of experiment indicates that values of h and z at l = 632,8 nm are more dominant than at l = 532 nm.    Key words: magnetooptic, specific rotary power, resonance frequency

Studi Interferometer Fabry-Perot Untuk Pengukuran Panjang Gelombang Cahaya

BERKALA FISIKA Vol 10, No 4 (2007): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

In this experiment, an interferometer Fabry-Perot method has been used to measure wavelength of diode laser. The first step is to calibrate the micrometer displacement using He-Ne laser in order to measure the diode and He-Ne wavelength. By shifting movable mirror, the transition of interference fringe in counted against the displacement of movable mirror. For the result of measurement, it is obtained for the wavelength of the red diode laser of, and green diode laser of.   Key word: Interferometer Fabry Perot, multiple beam interference.

Penentuan Koefisien Linier Elektro Optis Pada Aquades dan Air Suling Menggunakan Gelombang RF

BERKALA FISIKA Vol 10, No 4 (2007): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

The coefficients of electrooptics for water and refinery water in RF field have been determined. The RF frequency range used in the research is 6,04 MHz to 11 MHz. Two different light beam (532 nm and 632,8 nm) have been used to measure the change of light polarization after transmitted the samples. The result indicates that the linear and quadratic electro optic coefficients appear in the range of frequency-field. The refinery water has greater value of linear electro optic coefficient than aquades. It is also obtained that the greatest change of polarization angle take place when using the green laser in the field’s position of upright against the RF frequency field and polarization angle of 900.   Keywords: RF field, polarization angle, linear electro optic coefficient.

Sifat Optis Aktif Air dalam Medan Magnet pada Frekuensi Resonansi 50Hz-60Hz

BERKALA FISIKA Vol 10, No 3 (2007): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

The interaction between external magnetic field modulated at 50-60 Hz and the dipoles of the sample induced by laser light modulated at 50-100 Hz has been studied. The magnetic field has the maximum value of 170 mT produced by a coil of 810 in turns. The source of light of 632,8 nm and 532 nm is modulated at the resonance value between 30 Hz and 100 Hz. The optical characteristic behavior studied in this research is the change of polarization E-direction of laser light in the aquades samples against the influence of external magnetic field. The result of experiment indicates that the change of laser polarization angle is linearly proportional with the increaseasing of modulated frequency and external magnetic field in sample materials. It is shown that the change of glycerine concentration changes also linearly direction of polarization. The verdet constants measured in the experiment for 632 nm and for 532 nm equal to (0,026 ± 0,005) V (min/g-cm) and (0,025 ± 0,003) V (min/g-cm), respectively. Key words: change of polarization, external magnetic fields, resonance frequency

RANCANG BANGUN SISTEM PENGUKUR INTENSITAS CAHAYA MENGGUNAKAN MICROSOFT VISUAL STUDIO C# UNTUK MENENTUKAN SUDUT PUTAR JENIS LARUTAN GULA

YOUNGSTER PHYSICS JOURNAL Vol 1, No 1 (2012): Youngster Physics Journal Oktober 2012
Publisher : YOUNGSTER PHYSICS JOURNAL

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Abstract

A system of measuring the light intensity to determine the specific rotary angle of  sugar has been carried out. Research is done using a computer with a Microsoft Visual Studio C#. In this research there are some stages as follow light sensors and the system of measuring polarization angle. LDR as light intensity sensor, the result has been processed in a series of conditioning at the output signal. The result of  this series can be input in interface application.  Measurement of polarization angle can be done by counting average value of the intensity before it gets into the materials and thereafter. This system has been realized and can show the results obtained in the form of graphs and can be stored. The value of the angular turn kinds of sugar unmeasured is (51,33±0,42) omL/dm gram. Results of testing equipment and the characteristics of the sensor with a linear regression coefficient R2 = 0,9906 and  SD = 0,82. Keyword : Microsoft Visual Studio C#, Specific rotary angle, Polarization angle,  LDR

REVIEW PENGUJIAN HUKUM MALUS DAN SIFAT OPTIS AKTIF LARUTAN GULA MENGGUNAKAN SISTEM DETEKSI CAHAYA

BERKALA FISIKA Vol 16, No 1 (2013): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

Abstract In this paper, we review the test results of Malus’ Law and optical activity of sugarsolution using a system light detector. Two polarizers were used in the experiment to serve thechoice of a certain direction of electric field of light and to determine the change of polarizationangle. The change of transmitted intensity were measured using LDR detector which was thenacquisitioned by microcontroller and displayed via LCD and computer using  Microsoft Visual Studio C#. The experiment result is in agreement to the Malus’ Law with correlation coefficient of 0.99, and by using the equipment we obtain linearity between the change of polarization angle andconcentration of sugar solution, which is appropriate to the theory, as well. The specific rotarypower is (54±2) o/dm(g/mL) in the experimental uncertainty.Keywords: Malus law, change of polarization angle, light detector