Acoustics is the interdisciplinary science that deals with the study of all mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound and infrasound. Applications of acoustics are for instance the audio and noise control industries.

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Finding the wavelength of acoustic source underwater [closed]

I am currently working on a data fit assignment for my class and ran into some confusion. I will post the entire question here so you can get some background but the only question I have is with ...
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51 views

If we hear a noise long enough, is it going to settle as tinnitus? [closed]

Some equipment sometimes have a high pitch ringing, and I was wondering out of curiosity: can noises (not only drive you crazy but also) settle and become permanent ringing in your ear if you are ...
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Can Somebody give me Questions [closed]

Can someone give me questions on physics because I have my Examination tomorrow Class 9th (CBSE) topic : - Fluids(Density,buoyant Force , Archemedis Principal) , Work Power Energy(Work Basics, ...
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Can someone please explain the “infrared catastrophe”?

In my readings I've run into this idea of an "infrared catastrophe" associated with 1/f noise. As far as I can tell it is because when you graph the periodogram of the 1/f signal you see the PSD goes ...
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Math formula for crystal glass resonance [duplicate]

For a music therapy experiment, I have to use several crystal glasses with water and different cylindrical shapes, and make them vibrate and produce different sounds. Is there a math formula that ...
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79 views

Is Sound Considered a Subtopic of Physics? What are the SI Units of Sound?

Does physics cover sound? If so, why does sound not have units in the SI system, or how would we measure sounds and frequency? I guess it's debatable, but why isn't it standard practice in physics?
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help me.. please [duplicate]

I'm a total novice to physics so please forgive me but I'm looking for a starting point on sound, frequencies and everything to do with electricity. Preferably books because my internet usage is ...
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5answers
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Why does sound travel faster in iron than mercury even though mercury has a higher density?

The speed of sound depends on the density of the medium in which it is travelling and increases when the density increases. For example, in solids sound travels faster than in liquid and even faster ...
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30 views

Does the photon-phonon interaction always rotates the photon polarization of 90°?

I'm reading about the acousto-optic effect and on the Acousto-Optical Tunable Filters on particular and wanted to understand the physics under its working. I found this paper ...
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330 views

Why I hear sound from downstairs clearer than sound from upstairs?

In all the houses of two levels where I have been, why I hear the sound from downstairs clearer when I am at the second level, than I hear sound from upstairs when I am at the first level? Does sound ...
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140 views

Does gravity have any effect on sound waves? [duplicate]

If gravity at a place increases or decreases, does it affect the sound wave propagating through that place. If for certain place gravity increases on earth will there be change in direction or ...
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2answers
43 views

“In-head” sound intensity with and without earplugs

When you bite something in two pieces, e.g. a piece of hard candy, you hear the sound through two sources: vibrations in the air, entering your ears from the outside and internal vibrations in your ...
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137 views

'ting' 'ting' sound from a tube-light?

Whenever I light up a tube-light it makes 'ting' 'ting' sound every-time it blinks. I am talking about this tube-light Why is it so? I think its because of sparking(inside glass tube) ...
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50 views

How does the construction of a hydrophone differ from a microphone? [closed]

Both devices serve the same function, but a hydrophone must do it in a denser medium. What's the major difference in design? (besides being water-proof!) I'm asking about the relevant physics driving ...
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341 views

The shape of speaker cones

This is related to another question I just asked, but they are different enough I thought it deserved its own spot. Speaker elements seem to always be shaped like a cone with a portion of a sphere at ...
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3answers
117 views

The physics of sound boards

As a kid I was bemused at why soundboards worked. A small sound could be demonstrably amplified simply by attaching the source to a surface that is rigid and not too thick. How could the volume ...
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124 views

Does the frequency of a vibrating substance like a string depend on its properties or simply depend on the agent which vibrates the string?

We know that if someone vibrates a substance like a string, the string oscillates with its natural frequency. But I think the frequency depends on the rate the agent like a man's hand does vibration ...
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57 views

propagation of sound energy [duplicate]

In my previous questions like 'how do compressions and relaxation carry energy...' and 'how are they not isothermal...' and 'where does the heat come from in the compressed gas...',i've made ...
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71 views

Picking up audio using high speed video?

In the movie Eagle Eye, ARIIA (an intelligence-gathering supercomputer/AI) picks up audio using video recording of the vibrations in a coffee cup. How close is this to reality? I have see it done ...
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54 views

how does the temperature of a gas increase when compressed by an external agent during sound production? [duplicate]

Suppose a vibrating tuning fork compresses air molecules.And for this it has to do work.As compression occurs,its temperature increases.Does the energy spent by the fork go as the increased internal ...
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141 views

how do compression and expansion of air transfer energy(sound) and why it is adiabatic not isothermal?

Suppose a vibrating fork exerts force to the air particles to compress which leads to the increase of internal energy (heat).This heat or energy given by the fork is given to the next layer of air and ...
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1answer
95 views

How do speakers play sounds with multiple sources?

I know that speakers produce sound by creating a pressure wave, but I don't understand how when they play music or games you can hear the different sources. I guess what I'm asking is how do they play ...
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7answers
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Is it fair to judge this speedskating race by only 3 thousands of a second?

I'm reading this article: Zbigniew Brodka of Poland won the Olympic men's 1,500 meters speed skating title by just 0.003 seconds at the Adler Arena on Saturday. Brodka clocked one minute, ...
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96 views

Is the Doppler effect for sound symmetrical for observer or source movement?

It makes intuitive sense to me for the apparent frequency of a sound as modified by the Doppler effect to be based entirely on the speed at which the observer and the source get closer or farther ...
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Speed of sound at temperatures below 0 °C

How can the speed of sound be calculated for temperatures below 0 °C (down to -40 °C)? Does the calculation $v=331\ \frac{m}{s} + 0.6 \frac{m}{s°C} \times T$ still hold (where T's unit is ...
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83 views

Speed of Sound?

The speed of sound in a gas may be given by the following formula, $$c = (kRT)^{1/2},$$ where $k$ is specific heat ratio, $R$ is the gas constant and $T$ is the temperature. What are the limits of ...
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338 views

Why do you hear an acute sound when you rub your shoe on the floor?

Sorry for the silly question, but I've been wondering about this for quite some time. After raining when I get home I rub my shoe's wet outsole on the floor and I hear an extremely acute (high pitch) ...
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Nonsensical dispersion relations for elastic wave propagation

In an earlier question about Einstein notation, a link was provided to a medical paper which used acoustic propagation to noninvasively detect the orientation of muscle fibers. In short, muscle fibers ...
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1answer
198 views

Why does a cooling motorcycle make popping noises?

I was sitting in my parked car tonight when a Harley-Davidson motorcycle parked next to me. With my window down, I could hear that as the motorcycle was cooling down, it was giving off some type of ...
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223 views

Is it possible to create an audible sound source in mid air by intersecting ultrasonic sound beams?

In the book Daemon by Daniel Suarez a technique gets described, that enables a device to create an acoustical illusion of a moving person inside a house. Just then a voice called out clearly from ...
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56 views

What is the magnitude of the sound that a Helmholtz Resonator attenuates?

I know that the shape of the Helmholtz Resonator, specifically its neck shape and the volume of its cavity, determine the resonance frequency of the resonator. Moreover, the resonance frequency is ...
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1answer
72 views

Doppler effect observed in octaves

I have a question about the interpretation of the Doppler effect, when you look at the results as a change in octaves. Nothing actually changes when you look at the result in octaves instead of ...
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70 views

Car horn in the cold

I live in Chicago, where it is EXTREMELY cold right now. A couple of mornings ago it was -20C in the morning, and as I was driving through a parking lot a car pulled out of a space right in front of ...
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99 views

Is there a sound that explodes gunpowder? [closed]

Is there a certain frequency of sound/noise that will cause gunpowder to explode?
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61 views

Would it be possible to distinguish rap and singing from just seeing the soundwaves?

For any person even remotely familiar with music it is obvious that rap and singing are easily distinguishable (save for some interesting mix styles). This means that there must be a clear difference, ...
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66 views

Can I alternate between notes really fast and have it sound like a chord?

The question basically amounts to whether I can construct the illusion of superposition with adjacent sine waves of varying frequency. Context I'm trying to play music on a Tesla Coil (like OneTesla ...
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79 views

How can one calculate the distance a particular sound will travel?

What do you need and how to calculate a distance traveled by sound? For example if you hit a bell with a specific amount of power how far will it travel?
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77 views

Sound - for purposes of vibration

What is the best way to distribute noise from more than one source (I'm envisioning a system with many), within a dome, with the ground as its primary target, at optimal frequencies and volumes to ...
3
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1answer
67 views

Can a room resonate at a frequency lower than the principal frequency?

I'm the bass in our high school a cappella group. Recently we had a performance in our auditorium, and I am almost certain I heard the pitch an octave lower than I was singing. I was singing E3 (164 ...
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1answer
44 views

Predicting the direction of sound incorrectly? [closed]

When i was sitting outside my house yesterday, I heard a strange sharp sound. I could not point out it's exact direction but apparently looked like coming from left but later my friend told me that an ...
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1answer
232 views

How far do air particles move when a sound wave passes through them?

How far do air particles move when a sound wave passes through them? I know that they don't actually travel, the question is how far do they oscillate or what is the physical amplitude of the ...
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210 views

Could submarine SONAR kill a diver?

Could a diver swimming next to a submarine be killed or seriously injured by its SONAR? What physical aspect of SONAR affects the human body in a potential harmful way?
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Given stereo sound record, is there an algorithm extract the sound coming from a direction?

Given a stereo record of music with singing (2 channels), subtract the left-channel waveform by the right-channel's, you might get the music only without the human singing. The question is: can I, ...
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1answer
368 views

Why do we need hard steel balls to produce an unusual ‘chirping’ sound?

When two hard steel balls, or similar, are brought gently into contact with each other, an unusual ‘chirping’ sound may be produced.why do we need this material or shape to produce that sound?
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210 views

Why does a container with fluid make different sounds at different fluid levels?

Have you ever noticed that when you are filling a container with fluid. As it approaches the top, it makes a different sound? You can tell by listening when your about to reach the top. Why is this?
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4answers
213 views

Does a sound at 50dB at 1m have the same intensity of a sound of 51dB at 10m?

Does a sound at 50dB at 1m have the same intensity of a sound of 51dB at 10m, and also the same intensity of a 52dB sound at 100m?
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160 views

Is it possible to estimate the speed of wind by the sound emitted by a cable of an overhead power line?

I was near ($\approx40m$) an overhead power line and I heard a sound coming from the cables of the power line; I think the sound was made by the vibrations of the power cables due to the wind but I am ...
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155 views

Is speed of sound really constant?

Does not speed of sound actually depend on the frequency and/or amplitude of the waves? If so, why it is constant?
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278 views

Why does a “speed of sound” exist?

I've recently read that wind cannot be faster than the speed of sound (german source). But why is there a speed of sound? I understand (well, mostly accept to be honest) that the speed of light in ...
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89 views

Diffraction of sound

The sound waves, by the virtue of it being a wave, shows diffraction and interference. But in diffraction, I learnt that if the wave is allowed to enter through a small aperture, there is a central ...