Simple Experiment of Doppler Effect Using Smartphone Microfon Sensor

Doppler effect is the physical phenomena in which the emitted frequency is a source of change at a time when accepted by the detector due to relative movement of the detector towards the source of the wave or vice versa. This research aims to identify the Doppler effect symptoms by utilizing sensors found in smartphones. This research uses experimental method that combine the mechanical instruments and microphone smartphone sensor as measurement tool. The mechanical instruments used are a smartphone with the help of frequency sound generator software, Physics Toolbox, the camera as an instrument of data collectors, and Tracker as a motion analyzer software. Based on the results of the experiments, the author retrieved the value of the error and the standard deviation of each of the observed symptoms. The symptoms of Doppler effect upon source moving closer and moving away when the silent observer shows the error value of 0.04 % and 0.1185 % respectively with a standard deviation of 0.018 and 1.005. In addition, the experiment on Doppler effect as the source is staying still and as the observer approaching the source provides error value of 8.60 % and standard deviation of 13.501. As for the experiment on Doppler effect as the source and the observers are approaching each other displays the error value of 4.31 % and the standard deviation of 0.087. Overall, this experiment generates error value of 3.267 % and standard deviation of 3.665, inferring that the experiments conducted are accurate and precise in representing the Doppler effect phenomenon. Based on the results of this experiments, the researcher recommends to carry out practicum on Doppler effects with the help of smartphone sensors.

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PENGARUH TERAPI BACK MASSAGE TERHADAP PENURUNAN TINGKAT NYERI PADA PENDERITA RHEUMATOID ARTHRITIS DI DESA RAJADESA KECAMATAN RAJADESA KABUPATEN CIAMIS TAHUN 2018

Jurnal Keperawatan Galuh ◽

10.25157/jkg.v1i1.1836 ◽

2019 ◽

Vol 1 (1) ◽

pp. 1

Author(s):

Daniel Akbar Wibowo ◽

Dini Nurbaeti Zen ◽

Yalis Agustina

Keyword(s):

Rheumatoid Arthritis ◽

Standard Deviation ◽

Muscle Tension ◽

Massage Therapy ◽

Sampling Technique ◽

Total Sample ◽

Measurement Tool ◽

Pain Level ◽

Average Value ◽

Back Massage

Disease that is often complained by the public today one of the pain in the bone, which is better known by the community with rheumatism. Rheumatism or rheumatoid arthritis is a systemic, progressive, chronic and tendonic inflammatory disease of joints and connective tissue symmetrically. One way of management of rheumatoid arthritis pain is back massage therapy. Back Massage is one of the techniques to give massage action on the back with lotions/balm for 10-15 minutes, the warm sensation leads to vasodilation of blood vessels that will improve blood circulation in the area so that the activity of the cell is increased and will reduce pain, increase comfort, reduce muscle tension and improve physical and psychological relaxation. This study aims to determine the effect of Back massage therapy to decrease the pain level of rheumatoid arthritis patients in Rajadesa Village Rajadesa Sub District Ciamis District in 2018. Type of research using Quasi Experiment Design with one group pretest-posttest design. Total sample 48 respondents with total sampling technique. Data collection using experimental method with VDS (Verbal Descriptor Scale) pain rate measurement tool. The result of statistical test by using Linear Regression shows Sig = 0,000 <0,05, t value = 18,935> 2,012. Then Ha is accepted, and the average value before therapy is 3.27 with a standard deviation of 0.818, whereas after therapy is 2.23 with a standard deviation of 0.881, meaning there is the effect of back massage therapy on the decrease of pain level in patients with rheumatoid arthritis. So to reduce pain in patients with rheumatoid arthritis can be given back massage therapy.

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Thermal waves emitted by moving sources and the Doppler effect

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2021.121098 ◽

2021 ◽

Vol 176 ◽

pp. 121098

Author(s):

Roberto Li Voti ◽

Mario Bertolotti

Keyword(s):

Doppler Effect ◽

Thermal Waves ◽

Moving Sources ◽

The Doppler Effect

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The Doppler effect is the same for both optics and acoustics

Optik ◽

10.1016/j.ijleo.2021.167565 ◽

2021 ◽

pp. 167565

Author(s):

Shukri Klinaku

Keyword(s):

Doppler Effect ◽

The Doppler Effect

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ON THE THEORY OF THE DOPPLER EFFECT IN A MOVING MEDIUM

Modern Physics Letters A ◽

10.1142/s0217732398000024 ◽

1998 ◽

Vol 13 (01) ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

BRUNO BERTOTTI

Keyword(s):

Solar Wind ◽

Doppler Effect ◽

Dispersive Medium ◽

Time Derivative ◽

Optical Path ◽

Moving Medium ◽

Perturbation Theorem ◽

Hamiltonian Theory ◽

The Doppler Effect ◽

Definition Of

The increase in the accuracy of Doppler measurements in space requires a rigorous definition of the observed quantity when the propagation occurs in a moving, and possibly dispersive medium, like the solar wind. This is usually done in two divergent ways: in the phase viewpoint it is the time derivative of the correction to the optical path; in the ray viewpoint the signal is obtained form the deflection produced in the ray. They can be reconciled by using the time derivative of the optical path in the Lagrangian sense, i.e. differentiating from ray to ray. To rigorously derive this result an understanding, through relativistic Hamiltonian theory, of the delicate interplay between rays and phase is required; a general perturbation theorem which generalizes the concept of the Doppler effect as a Lagrangian derivative is proved. Relativistic retardation corrections O(v) are obtained, well within the expected sensitivity of Doppler experiments near solar conjunction.

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