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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How can people do music with Tesla coils?

I saw a lot of videos of Tesla coils doing music on YouTube. And I wonder how can they do that sort of things. How they can calculate what tone it is going to do? And what are the factors to ...
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124 views

Will timbre/quality be different if two different people play the same guitar? [closed]

Will timbre/quality be different if two different people play the same guitar? Assume that frequency/pitch and amplitude are same.
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How does a speaker produce sound?

What I read is that a speaker produces sound by the movement of a coil attached to a cone which moves back and forth. So, If I try to move the coil by hand, would it produce sound? If not, why? or Why ...
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Does EM radiation (any, i.e. RF), or sound, radiate everywhere at once?

I am having trouble understanding electromagnetic radiation (or waves in general, be it EM or sound). If I have a 1 Watt speaker, is it infinitely divided and spread out so that everyone in every ...
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Riddle about speed

This stems from a riddle I read in a magazine perhaps 20 years ago so I apologise for the imprecise recollection. A dog that can run infinitely fast is placed on an infinitely large flat surface and ...
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Why can't echoes be heard inside a room?

If I go camping and shout anywhere, in the forest or on a cliff, I usually hear the echo of my voice. Why when I shout in my room I do not hear any echoes?
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How to distinguish female and male voices via Fourier analysis?

What makes one, without looking, be able to identify the gender of the talker as male or female? I mean if we Fourier analysed the voice of males and females, how the 2 spectrums are different which ...
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Is it possible to break bulletproof glass with your voice?

In The Adventures of Tintin, an opera singer (the Milanese Nightingale) broke a bulletproof glass case using her voice. Is that scientifically possible? From the Wikipedia page, a typical bulletproof ...
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Why do bass tones travel through walls?

I was in the shower while my roommate was listening to music and got to thinking about the fact that I could only hear the bass and lower drums through the walls. Why is this? The two possibilities I ...
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127 views

What theory is the person in this song talking about?

What he is talking about sounds interesting to me, and I would like to know more. But I need to know the name first. http://www.youtube.com/watch?v=Ogn5FrVGtAg&hd=1
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Decibel level addition of multiple noise sources

If I have four computer fans of which each is said to run at 46 dB, and they run close to each other, how loud is the whole system? I somehow recall from my physics course that 10 decibel ...
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How can a sine wave represent a longitudinal wave?

I envision a longitudinal wave as a series of vertical lines like that drawn on the board in an introductory physics class. This image contains no angles. Sound is a longitudinal wave. Some ...
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201 views

Drum head coupled with an RLC circuit

I'm thinking about the possibility of an electroacoustic drum that would be tuned with some kind of RLC circuit. The drum head would have an electromagnet attached to its center, which would be ...
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163 views

Is there a theortical limit to the amount of sound-energy air can contain?

is there a theoretical limit to the amount of sound energy air can contain? In case, there is a limit, what is that limit?
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642 views

The definition of “frequency” in different contexts

I have been doing some research on all kinds of sound-related topics lately and have been a bit confused by the different uses of the term "frequency". Of course, the most general meaning of frequency ...
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4answers
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Why can I tell a flute from a trumpet?

The usual story I've heard describing the difference between a 440 Hz note played by a flute and a trumpet is that the overtones are different. That is, if you play a note at 440 Hz, there will also ...
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275 views

What Is the Noise of an MRI Machine

What is the source of the loud noise of an MRI medical scanning machine? Is it due to some mechanical moving parts such as pumps, or is it an effect, similar to magnetostriction of superconducting ...
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1answer
861 views

Can sound be used to purify/filter water?

I remember reading about all chicken at a poultry farm being violently sick/dying for apparently no reason. It turned out the culprit was machinery at a nearby factory that emitted sound at a ...
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436 views

There is absolute silence?

Silence is a relative or total lack of sound. But it is possible for real? Is there any way to achieve this?
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1k views

Ceramic vase filled with boiling water makes a sound. Why?

I had some old flowers in a vase and noticed the water had become really stagnant, causing the whole room to smell like a fart. So I tipped out the flowers and the old water, and poured some boiling ...
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675 views

Why do I hear beats through headphones only at low frequencies?

I was recently playing with this Wolfram Demonstrations applet, which demonstrates beats. At first I thought the app didn't work because I couldn't hear any beats. Then I realized that the applet ...
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792 views

Hearing a sound backwards because of Doppler effect

Consider a supersonic plane (mach 2) aproaching a stationary sound source (e.g a fog horn on a boat). If I understand it correctly, the passengers in the plane can hear the sound twice. First at a 3 ...
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4answers
688 views

Why does the fundamental mode of a recorder disappear when you blow harder?

I have a simple recorder, like this: When I cover all the holes and blow gently, it blows at about 550 Hz, but when I blow more forcefully, it jumps an octave and blows 1100 Hz. What's the ...
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172 views

Remnant of a supernova [duplicate]

i explain better A supernova remnant is the structure resulting from the explosion of a giant star . The supernova remnant is surrounded by an expanding shock wave that is formed from material ...
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1answer
862 views

Sound velocity in water

Conductivity, temperature, depth sensors are used by oceanography to calculate the velocity of sound at varying depths. These measurment values are used to comprise sound velocity profiles like the ...
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1answer
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Does the absence of a sound particle indicate that there are no photons?

Sound is usually referred to as just "sound waves" - we do not talk about a "sound particle" and only as a wave or "matter wave." Could something similar apply to light i.e. that there really is no ...
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295 views

what is the relationship of sound volume to atmospheric pressure?

what is the relationship of sound volume to atmospheric pressure? if I was in a plane with a cabin pressure equal to 8000 feet would the volume drop be noticable?
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How does gravity affect sound waves?

Someone asked me this question and I don't think I gave him an adequate answer (I was trying to think of the extreme case - that of neutron stars)
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Understand audio signals

Most audio signal are described by a curve having two parameters: The amplitude and the frequency (amount of time from positive to negative amplitude value). What I want to understand is how the ...
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Why do power lines buzz?

When near high tension power lines, particularly after a good rain, the lines themselves emit a buzzing noise. A similar noise can be heard coming out of the electric meters attached to my apartment. ...
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How does paper make sound when it is torn?

We know that from our experience when we tear up a piece of paper, we can hear a characteristic sound. What is the underlying mechanism behind it? What do the dominant frequencies (edit: I don't mean ...
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538 views

Why does my bicycle brakes squeak in the morning?

Every morning, when I ride my bicycle, there is a very loud squeak coming from the brakes. I have an aluminum rim (I think that they are of the sprint type) and rubber pad brakes. A couple of brake ...
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How long do reflections take?

How long does it take for a photon to be reflected? Starting with the photon being absorbed by some atom to the point it's reemitted? And what's the same point with pressure waves, like sound?
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How can a Human voice or animal voice have unique frequency

Well this is pretty noobish question and I am not sure how to ask. When We talk we don't talk in an uniform frequency. Then how can one measure frequency of ones sound/voice ? I am asking this cause ...
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If sound wave is going to hit any metals can it make that metal electrons into exited state?

What will happen when sound wave hits the metals with very high frequency can it make the electrons to exited state. If it happens then what will be the state of that metal
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Do sound waves bend and/or diffract?

Sound waves are normally mechanical wave i want to know whether the sound wave bends if it bends does it undergo diffraction just like light wave?
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A new idea on unifying sound and light [closed]

Got a new idea regarding the unification of light wave and sound wave into a single entity , may be probably a wave. Is it possible to proceed in that manner,and has it been done previously,like i ...
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How many boats does it take to find an acoustic buoy by Doppler shift?

Inspired by this question on the Doppler shift, suppose there is buoy somewhere on the surface of the ocean emitting a pure frequency. You get to place some boats wherever you want on the surface of ...
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4answers
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Doppler effect of sound waves

I am looking for interesting ways to introduce the Doppler effect to students. I want some situations in nature or every day life, where a student is possibly surprised and may ask "how could it be"? ...
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428 views

When water is about to boil

Have ever noticed? When water is about to boil, no matters the kettle, there is some sound I have no idea where it comes from, sometimes long before it boils. Is there any explanation for this ...
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How sound intensity (dB) and sound pressure level (dB) are related?

Source: http://www.engineeringtoolbox.com/sound-power-intensity-pressure-d_57.html Both sound intesity and pressure level are measured in dB. Given a specific sound, are these two dB values the same? ...
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3answers
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Design of a common table fan

A few questions about the design of a common table fan, such as below. Does the round disc (silver in the image) in front of the blades serve any functional purpose? Does the metal casing around the ...
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Does a second similar source of white noise increase the overall noise level?

If I put next to my cooler another similar cooler that produces similar white noise, will the overall noise level increase? I want to point out that I am speaking about adding another independent, ...
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380 views

Modelling noise with distance

I was wondering about the relation between noise with distance, assuming a point source, using sound as the method for communication and air as the medium of communication. Obviously as the distance ...
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301 views

How do animal perceive distances with their eyes and ears

I am studying how animals (including the human beings) can perceive distances thanks to their eyes and their ears. I am focusing on the fact that they always go in pairs: two eyes, two ears, etc. ...
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Is it possible for wind to break the sound barrier?

I understand that in nature wind would never get high enough, but I am just curious as to whether physics would allow this to occur or not.
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What happens to sound waves?

I apologize if this is a naive question, but I never really learned about this. I'm curious as to what happens to sound waves after they are "used"? For example, if I say something to you verbally, ...
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Phonons in non-crystalline media

Do sound waves in a gas consist of phonons? What about a glass? Or other non-crystalline materials such as quasicrystals? How does the lack of translational symmetry affect the quantization of the ...
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What is the source of high-frequency squeal in faulty CRT monitors and TV, and what is physics of generating this sound?

Sometimes old faulty CRT monitors generate nasty high-frequency squeal sound. What element might be responsible for generating such sound? I have heard that it might be dry electrolytic capacitor; ...
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Why is the decibel scale logarithmic?

Could someone explain in simple terms (let's say, limited to a high school calculus vocabulary) why decibels are measured on a logarithmic scale? (This isn't homework, just good old fashioned ...