# Tag Info

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Well i think yes because we can change one form of energy into other form so sound is also a type of energy that's why its possible to change it into electricity......

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Thunder is a sonic boom, generated by the rapid heating of the atmosphere by the lightning discharge. The heat front moves faster than sound, generating the sonic boom. Thus what you hear is a pressure wave, and it can be carried by plasma, gas, liquid, or solid: by all of the states of matter.

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A more accepted term for sound treatment is acoustic treatment. Acoustic treatment deals with the quality of sound, whereas sound proofing deals with the attenuation of sound. A recording studio may need to be acoustically treated in order to increase the fidelity of the recording equipment. It also may need to be sound-proofed in order to avoid ...

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A permanent magnet has a fixed north/south polarity - in this example, lets say north is facing up and south is facing down. This magnet has a membrane of some kind attached to its north face. An electromagnet beneath the permanent magnet can switch the direction of its north/south polarities by changing the direction of the electric current running ...

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There are two ways to describe a sound wave. One is in terms of displacement of the medium and the other is in terms of pressure. This simple diagram shows that tthe two descriptions are $90^\circ$ out of phase with one another. Note that at a compression $C$ where the pressure is a maximum the displacement of the particle is zero and the same is true ...

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These curves show acoustic displacement or acoustic velocity. For acoustic pressure they would be "inverted" (nodes at the open end, antinodes at the closed end). In presented 1D case are all of them actually scalars (or can be treated as such). The curves show just the magnitude. I know, these graphics are confusing. Nowadays it could be easily done by ...

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Sound waves are made of alternation of compression (higher density) and rarefaction (lower density) regions in the air. However, this can be somewhat difficult to visualize. Because of this, textbooks often show the wave like it's a string in the organ pipe. Really what the curves are showing you in the amplitude of this compression wave. It's also drawn ...

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Positrons and antiprotons are contained and manipulated with electromagnetic fields, as they annihilate when close to matter atoms and molecules. The only neutral atomic antimatter at the moment is the creation of antiHydrogen in labs. Have a look at the ALPHA experiment at CERN. Acoustic manipulation presupposes bulk matter, the kind that goes with 10^23 ...

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Acoustic levitation requires a material medium to transmit the sound waves that suspend the object you want suspended. The object must contact the medium in order to be suspended. If the object is made of antimatter, it will instantly annihilate upon contact with the material medium that transmits the acoustic waves. You can't transmit acoustic waves in ...

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The answer can be found at the sound stackexchange - if you take a pure tone and reverse the phase of one of the stereo channels, there is no "sensible" direction in front of the listener that the sound could come from. We then conclude that the sound comes from behind us (because we have poor ability to figure out the direction of sounds behind us because ...

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That's almost duplicate of this question. You should definitely read it. It's caused by the change of propagation media. If you shout, the sound is produced by the disturbances of the airflow done by your vocal folds. Again: the airflow. Then it must overcome the huge impedance change to the water (and there comes the loss of power). And from the water to ...

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Expounding on the 1st part of @Einchenlaub's answer (and describing my favourite example), The Cochlea in the ear (in which the hair follicles are present) is a beautiful example of how the fourier transform is carried out physically. The changing diameter of the cochlea's tube causes different frequencies to resonate in different parts of the cochlea, so ...

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Perhaps a better way to put this question is how is energy concentrated within a resonant system? As others have already stated energy is always conserved if one considers the universe in tallying where energy comes and goes. But if you are considering a system, defined within spatial boundaries, the system can lose or gain energy through its boundaries. In ...

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This is a common misconception. The function above can be interpreted as follows. Sound of frequency $\dfrac{\omega_1+\omega_2}{2}$ with amplitude modulated by the cos function of frequency $\dfrac{\omega_1-\omega_2}{2}$. The cosine function becomes zero twice every cycle as well as reaching a maximum magnitude twice every cycle. So the intensity of the ...

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Such a thing is generally possible. You can test this really easy: take a tuning fork without resonator (so really just the fork itself), hit the desk, hold the fork in the air and listen. You will probably hear almost no sound. Now plug your ears, do the same and press the fork root against your forehead. You will see (hear :-) ). Practically, that's a big ...

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You would. The bones in your arms would conduct the vibrations to your ears, though I'm not sure you could really call that hearing. The bones in your ears and near your ears would certainly feel the vibrations, but without some sort of mechanism that changes vibrations in solid matter to sound, you wouldn't exactly hear it. You hands, however, would ...

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Edit: I think you'll find all the details you need at this question. As Asher commented, when a wave is described as sinusoidal, or triangular, or square, that's its amplitude profile. When a wave is described as plane or spherical, that's the spatial profile perpendicular to the direction of propagation. For example, a plane wave of sinusoidal ...

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As far as I understand wave physics, the only way to reflect a wave is to have a change in the medium they are travelling through. Two waves can have constructive or destructive interference however but to reflect each other isn't possible.

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Imagine a metal rod and you hit one end of it with a hammer. A compression pulse travels down the rod and back again after reflection at the other end and the cycle of reflections is repeated - this is a longitudinal wave motion. However as the pulse travels down the rod I would imagine that the walls of rod bulge out and then return, so this is equivalent ...

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Sound is a longitudinal wave and propagates from the solid into the gas as a longitudinal wave. It is possible to get transverse waves in solids and they are generally known as shear waves. However we would not normally describe a shear wave as a sound wave. Shear waves in a solid will not propagate into a gas. They would simply reflect off the solid gass ...

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Just think about how you might push a child's swing. You apply a push once every oscillation of the swing and thus build up the amplitude of the swing. This is a resonance condition whereas if you pushes the swing at a slightly lower frequency you would not be able to increase the amplitude of the swing as much. Once the swing is at a constant amplitude ...

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My best guess is that you would need to use a ultra high frequency played directly into a small body of water. Theoretically it could be done but actually doing it would be an immense task that I doubt anywhere other than the best lab could do

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First, yes the speed of sound is the limit of the group velocity at small wave vectors. In the limit of small wave vectors (long wavelengths), the material acts like the continuum material we see at a macroscopic scale. (You don't see any atoms with your eye. Macroscopic materials appear to be infinitely divisible.) The speed of these long-wavelength waves ...

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Sound waves are pressure waves. We measure it as a logarithmic ratio of intensity. Sound intensity is a useful parameter to measure because it's related to the energy incident on a surface which can be easy to measure. Sound intensity is proportional to pressure squared. When calculating decibels we would have to handle that like so: I = ...

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I think there is a problem in your question, cause "sound" is a phenomena in the meaning of process. When we talk about renewable energy, we in fact generally discuss sources (E.g. sun, not EM waves). Straightforward and basically there are two, mostly engineering problems: Sound is a mechanical wave of a very low energy compared to industrial processes ...

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Sound could be considered a renewable resource if taken from a source that was created by continual physical processes - such as the sound of waves crashing against rocks. Although those sound waves contain energy (which is the kinetic energy of moving/vibrating air particles), their energy density is very low. Therefore they are not useful for generating ...

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I think you might be a little confused. The phrases 'renewable energy' and 'un-renewable energy' are used to refer to industrial sources of energy. These industrial sources include Wind, Solar, Wave, and Nuclear power, and traditional fossil fuels (coal, oil, natural gas etc.). If a source of power is renewable, it is not depleted (used up) when utilised ...

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You need to find the $k$ vector in the medium. $$k = \frac{2\pi f}{v_m}$$ where $v_m$ is the speed of sound in the medium, which can be found from the dispersion relationship $$v_m = \frac{1}{\hbar}\frac{\mathrm{d}E}{\mathrm{d}k}$$ The intensity has nothing to do with phonon energy. Intensity provides the total energy incident in a unit area. Typically ...

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There are three points to be noticed: If you just blow without closing the lips, you would change the boundary condition. The trumpet waveguide is not "nicely predictible", the approximation of an open tube does not work cause the bore variations $S(x)$. You need to solve this kind of beasts for reasonable 1D propagating pressure approximation: $$... 0 When I google "speed of sound water temperature" the first hit is http://www.engineeringtoolbox.com/sound-speed-water-d_598.html Which contains tables of speed with temperature. Interpolate, calculate, enjoy. 2 You will get destructive interference when the difference in the distances from you to the two speakers is n + \tfrac{1}{2} wavelengths. In your case that's 0.68m, 2.04m, 3.4m, and so on. You get constructive interference when the difference in the distances is an integral number of wavelengths. However the experiment is hard to do in a living room ... 2 Based on the results, the pipe is clearly open at one end but closed on the other. Therefore \lambda_n = \frac{(2n+1)L}{4} Your formalism is a bit unusual. If I can advise you, try to use something like this for harmonics:$$f_n=\frac{c}{\lambda_n} = and \ so \ on$$Show explicitly the dependency on n. 3 A few observations. First - if you record sound for a short time, the bandwidth of the sample will result in a smearing of the peaks. This only really matters if the sample is very short - with a 1 second sample you would have 1 Hz resolution, but if you sample for 0.01 second, the bandwidth is 100 Hz. Second, you are using a scale that is quite compressed ... 2 Since this is clearly homework and excercises question, I will provide just hints. This kind of treatment is the same how beats are descripted. Study this article, it will help you get that. Since k=\frac{\omega}{c} where c is constant and the distance is the same for both the signals, it will not cause any more uncertain phase shifts. 2 In principle, yes. Sound waves are compressions in a medium, which in principle can be seen if the density contrast between wave crests and troughs is large enough, and the wave speed is small enough. In "everyday object", such as the air, neither of these conditions are fulfilled. But one example of visible sound waves are the so-called baryonic acoustic ... 1 Blind people see in their brain 3 dimensional images with echo location. When they hear sound it can be interpreted as color or shapes. Also if you put a vibration to your closed eyes you'll see all kinds of patterns of color simulator to pressing on them. 2 Yes. High intensity low frequency sound makes your eyeballs vibrate in your head, so you really can see (and feel) it. On a related topic, you can find the damped resonant frequency of your eyeballs by looking at the sweep line on an oscilloscope whose timebase has been set to around 50mS. If you then hit yourself downwards on the top of your head you will ... 9 What we perceive as "sound" are (mechanical) oscillations of molecules from the source to the ear. This is for example why you cannot hear anything in vacuum, because there is no matter to oscillate. Light on the other hand is an electromagnetic wave. Therefore, there cannot be sound in our visual spectrum. It's in the wrong category. However, if you want ... 4 No, there is not. The eyes are receptors of electromagnetic waves and therefore they don't percipe sound. However, there are cases when you actually can see a sound effect on your own eyeballs, but they are unusual and a bit crazy. E.g. if you play low frequencies on a trombone and watch a screen with some repetition rate, then you can sometimes see an ... 3 The basic phenomenon is that high frequency sound is more strongly attenuated than low frequency sound. The mechanism for sound attenuation is viscous damping. The absorption coefficient is$$ \gamma= \frac{\omega^2}{2\rho c^3}\left[ \frac{4}{3}\eta + \zeta + \kappa\left(\frac{1}{c_v}-\frac{1}{c_p}\right) \right], $$where \omega is the frequency, \rho ... 1 In most media, high frequencies will be attenuated more strongly than low frequencies. Even if the loss mechanisms are the same, for a certain amplitude a higher frequency wave will have a greater velocity (displacement of particles, not wave velocity), and thus greater "drag" per cycle. If the loss mechanism is the same, then the wave will lose the same ... 0 I do not know that it has been done before, but I have no doubt there is a difference. What is not clear is if it would be noticeable by human ear. The difference is explained theoretically by the fact that the string will vibrate different with the supporting body. Only in the hypothetical scenario where the string is held by ideally unmovable holders ... 0 If the duct structure has passive modes that are within the bandwidth of the 'noise' you are imposing, and the active controller they can sap and release energy resulting phase shifts. Also the tube like structure whether closed or open will impose a standing wave resonance with all the possible harmonics that may be near or not near to the frequency you are ... 1 How much sound colliding objects make depends entirely on the objects and the medium they are in. In the vacuum of space collisions don't make a sound, at all. In Earth's atmosphere the total energy of sound released by collisions that are caused by solid objects is very small compared to the energy of the objects. This is because of the large difference in ... 2 Well, there is one simple thing you should do and that's doing that in right units:$$ p = A\sin (\omega t - kx) + B\sin(\omega t + kx) $$Wthout k and \omega you can't add/subtract x\pm t. As CuriousMind has commented, it doesn't matter which direction the coordinates axes takes. For these kind of applications there is better suited solution:$$ ...

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A sound wave moving through a gas requires a small scale bulk movement of gas molecules back and forth as pressure at any locations builds or falls. Therefore, the sound wave can not possibly move through the gas at a speed greater than that of the individual molecules themselves, and in fact must move at a lower speed than that due to the random nature of ...

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Wikipedia states that The high frequency response of vinyl depends on the cartridge. CD4 records contained frequencies up to 50 kHz, while some high-end turntable cartridges have frequency responses of 120 kHz while having flat frequency response over the audible band (e.g. 20 Hz to 15 kHz +/-0.3 dB).[5] In addition, frequencies of up to 122 kHz have ...

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i've programmed some shepard tones and even a voice generator. The human voice can't make that sound for the same reason that a single or even 3 trumbones couldn't make it. if you had 12 trumbones you could conceivably put them on a wheel system so that the pitch of each is increased and when the top one reaches to top is muted and send down to the lowest ...

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Playing a vinyl "LP" implies a 33 rpm motion and 30 cm diameter. The highest frequency recorded will depend on the track velocity and the size of the needle. 30 cm diameter implies a 100 cm track length (roughly - less as you move further in) traversed in about 2 seconds - or 50 cm / second. The radius of the needle is specified in the standard as less than ...

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Consider that the only frequencies present on the disk are spatial frequencies. The spatial information only gets transformed into the temporal domain when you spin the disk, and the scaling depends entirely on how fast you spin it. How fast can you rotate the disk? If a disk that nominally rotates at $33 \frac{1}{3}$ rpm is able to represent frequencies ...

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