Figure - uploaded by Michael Hirth
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A xylophone consists of several wooden or (as in the picture) metallic bars that can be excited to flexural vibrations by hitting them with mallets. The bars are fixed with pins on two felt strips with the aim to dampen the first (not harmonic) overtone.
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A variety of experiments with smartphones and tablet PCs allow a precise analysis of acoustic
phenomena. For example, we recently described an experiment in which a noise signal
simultaneously triggered harmonic acoustic resonances in the air column of a tube open at both
ends and a tube closed at one end. The measuredresonant frequencies were used...
Context in source publication
Context 1
... of the instrument by blocking or opening holes. The overtones of a xylophone as an example of an idiophone are not harmonic, i.e., pitches of the overtones are not integral multiples of the fundamental pitch. With the aim to improve the quality of the emitted sound, the xylophone bars are clamped at specific positions to dampen the first overtone (Fig. ...Citations
... • mechanics (Chevrier et al., 2013;Gabriel & Backhaus, 2013;Darmendrail & Müller, 2021;Hochberg et al. 2016;Koleza & Pappas, 2008;Kuhn & Vogt, 2013;Monteiro et al., 2014;Shakur & Sinatra, 2013) • waves and acoustics (Castro-Palacio & Velázquez-Abad, 2013;Parolin & Pezzi, 2013;Sans et al., 2013;Forinash & Wisman, 2012;Greenslade, 2016;Hirth et al., 2016;Vogt et al., 2015;Darmendrail & Müller, 2020;Darmendrail & Müller, 2021) • optics (Klein, et al., 2014;Thoms, et al., 2013) • electromagnetism and radioactivity (Forinash & Wisman, 2012;Silva, 2012;Keller et al., 2019). From a teacher's perspective, the use of MDETs considerably enhances their freedom in laboratory work, enlarging the range of possible student experiments, and sometimes requiring less budget, effort, preparation and time as conventional experiments. ...
The present text provides a short, non-technical account of some historical and educational background and, based on this, of the rationale of the use of mobile devices in physics education.
... All 6 master of physics mechanics experiment sets by applying the sensors on smartphone as a measurement tool are developed in this research can be used to test the parameters and parameters that need to be studied precisely and accurately. (Huffling et al., 2014;Sans et al, 2015;Vieyra et al, 2015) และการทดลองในรายวิ ชาฟิ สิ กส์ 2014;Oprea and Miron, 2014;Liu et al, 2017;Chevrier et al, 2013) นอกจากนี ้ ยั งมี นั กวิ จั ยที ่ ประยุ กต์ ใช้ เซนเซอร์ วั ดความเร่ งในการทดลองการตกอิ สระ (Vogt, Kuhn, and Müller, 2011;Madansingh et al, 2015;Kuhn et al, 2016) การ หาค่ าสั มประสิ ทธิ ์ ความเสี ยดทานจลน์ ของวั ตถุ ที ่ เคลื ่ อนที ่ บนระนาบเอี ยง Baldock and Johnson, 2016) การเคลื ่ อนที ่ แบบหมุ น Umek and Kos, 2016;Klein et al, 2017;Hochberg et al, 2014;Castro-Palacio et al, 2014;Patrinopoulos and Kefalis, 2015) การคลื ่ อนที ่ แบบกลิ ้ ง (Puttharugsa et al, 2016) การเคลื ่ อนที ่ แบบแกว่ งกวั ด (Castro-Palacio et al, 2013; (Chevrier et al, 2013;Hochberg et al, 2014;Shakur & Sinatra 2013) คลื ่ นเสี ยง (Greenslade, 2016;Hirth et al, 2015;Müller et al, 2016; ความดั นของ ของเหลวและก๊ าซ (Monteiro et al, 2016;Macchia, 2016;Vieyra, Vieyra, & Macchia, 2017;Monteiro & Martí, 2017) ทั ศนศาสตร์ (Klein et al, 2014;Thoms et al, 2013) แม่ เหล็ กไฟฟ้ า (Forinash & Wisman, 2012;Silva, 2012 ...
... To measure the speed of sound in a rod, it is very common to use the free-bar configuration with longitudinal excitation that allows us to measure the fundamental frequency of the induced vibration [7,8] making use of the relationship. ...
A couple of experiments analyzing the vibration of bars in different configurations using as a vibration sensor an electric guitar pickup are presented. The device is a versatile and easy to operate sensor that can be used in experiments involving the analysis of vibrations in rods and bars of different composition and in different configurations. This technique is presented with two simple experiments: in one, the vibration of a small rod in a cantilever is analyzed, and in another, the longitudinal vibrations of a rod is measured in order to calculate its propagation speed.
... Given that nearly all undergraduate students have access to a smartphone, this powerful and portable computer provides a compelling alternative to conventional RF analysis equipment. Over the past ten years, much has been written about the use of smartphones for acoustic measurements [5][6][7][8][9][10][11][12][13][14] and scientific measurements in general. [15][16][17][18][19][20] Due to the ease of interfacing with the internal microphone and the limited bandwidth of the smartphone analog-to-digital converter (ADC), the studies mentioned above have focused almost exclusively on the use of the internal microphone to make measurements of sound in air and in the audible frequency range. ...
A simple and inexpensive approach to acquiring signals in the megahertz frequency range using a smartphone is described. The approach is general, applicable to electromagnetic as well as acoustic measurements, and makes available to undergraduate teaching laboratories experiments that are traditionally inaccessible due to the expensive equipment that are required. This paper focuses on megahertz range ultrasonic resonance spectra in liquids and solids, although there is virtually no upper limit on frequencies measurable using this technique. Acoustic resonance measurements in water and Fluorinert in a one dimensional (1D) resonant cavity were conducted and used to calculate sound speed. The technique is shown to have a precision and accuracy significantly better than one percent in liquid sound speed. Measurements of 3D resonances in an isotropic solid sphere were also made and used to determine the bulk and shear moduli of the sample. The elastic moduli determined from the solid resonance measurements agreed with those determined using a research grade vector network analyzer to better than 0.5%. The apparatus and measurement technique described can thus make research grade measurements using standardly available laboratory equipment for a cost that is two-to-three orders of magnitude less than the traditional measurement equipment used for these measurements.
... For example, [24] gives preliminary results showing the feasibility of such a study and also the good agreement that can be obtained between the theoretical results and the experimental data obtained with the smartphone. Later on, while this paper paper was under consideration for publication, [31] has been published on the same subject. This work [31] studies the resonant frequencies of rods clamped at different points with clothes pins. ...
... Later on, while this paper paper was under consideration for publication, [31] has been published on the same subject. This work [31] studies the resonant frequencies of rods clamped at different points with clothes pins. Some characteristics of the students' experimental work with smartphones have proven to have a positive influence on the learning outcomes. ...
Modern smartphones have calculation and sensor capabilities that make them suitable for use as versatile and reliable measurement devices in simple teaching experiments. In this work a smartphone is used, together with low cost materials, in an experiment to measure the frequencies emitted by vibrating rods of different materials, shapes and lengths. The results obtained with the smartphone have been compared with theoretical calculations and the agreement is good. Alternatively, physics students can perform the experiment described here and use their results to determine the dependencies of the obtained frequencies on the rod characteristics. In this way they will also practice research methods that they will probably use in their professional life.
Smartphone sensors have been widely researched and published in literature by experts to be used in physics learning. This paper presents the use of smartphone sensors and applications as a measuring instrument in the classical sound wave experiment adapted from physics textbooks at school or university. Tone generator, sound meter, and audio autocorrelation were used in the experiment to visualize sound as a propagating vibration, sound waves as mechanical waves, characteristics of sound waves (loud and soft or high-pitched or low-pitched), sound range, and sound power. The experimental results presented are expected to help students understand the concept of sound waves.
The interest in achieving improved acoustical conditions in classrooms has increased in the last years. Some experiments on acoustics phenomena using smartphone applications appear in the recent bibliography. In this paper, we present a proposal for active learning about room acoustics for high school and undergraduate students. Students work on the concepts of reverberation and intelligibility through a set of activities centered on speech communication in the school. For experimental work, they use smartphone applications. At the end of the work, students would be able to suggest some actions to improve acoustic comfort in school.
Mithilfe der App Audio Kit oder anderen Schallanalyse-Apps können Schallsignale analysiert und Töne definierter Frequenz generiert werden. Durch die Möglichkeit, Oszillogramme und Frequenzspektren darzustellen, Schallpegel zu messen und Töne zu erzeugen, ergeben sich vielfältige Experimentiermöglichkeiten im Themenbereich Akustik. An dieser Stelle soll die Untersuchung verschiedener Schallarten ausführlicher beschrieben werden.
In this article, we present the use of smartphone sensor to measuring and analyzing the parameter of sound waves, for teaching and learning in sound waves. By using the acoustics/microphone sensors on smartphone to measurements of the speed of sound both in air and gasses mixture. By install program (application) on smartphone has been shown the experimental results on screen. Additional, acoustics/microphone smartphone sensors can be measured and analyzed the beat frequency and tone harmonics. The acoustics/microphone smartphone sensors have advanced for usefully teaching and learning in sound waves.
