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5

Put more simply: sound waves are attenuated as they propagate through air (this is more easily measured for very short wavelengths, e.g. ultrasound). This means they lose energy - which is turned into heat of the air. The amount of heating, however, is very very small. Let's do the math. A sound wave of 120 dB (really loud) has energy of only $1 ...


1

A qualitative picture of what happens in a gas can be made in terms of whether the behavior is random or non-random, oscillatory or steady. Temperature describes the random motions of the particles that comprise some object. Correlations, if they exist, disappear rapidly with distance between particles. In an ideal gas, correlations don't exist, period. ...


6

Sound waves do generate changes in temperature because the propagation of sound is an isentropic process. Keep in mind though that changes in static temperature can very well occur without the generation of heat. Moreover, the pressure changes associated with sound waves are of such a small magnitude that the observable temperature changes are minimal (but ...


3

Heat corresponds to random movements of atoms and molecules. It travels only through conduction - slowly. Sound consists of ordered movements, travelling through a medium as a wave (although it can also stand still, as in a standing wave). Large numbers of atoms or molecules move back and forth in synchrony. Sound eventually becomes random, as it is ...


1

There's not much difference. Thermal vibrations would be perceived as sound (noise) if they were intense enough, but they are not. The thermal vibration amplitudes at room temperature are small enough that the ear is not sensitive to them. I've been told that the sound pressure level for thermal vibrations is close to, but below, the threshold of ...


3

A plank is a complicated example to choose because it's a composite material with a complicated structure. A better choice would be a piece of iron or some other homogeneous material. In that case the speed of sound is given by: $$ v = \sqrt{\frac{K + \tfrac{4}{3}G}{\rho}} $$ where $K$ is the bulk modulus and $G$ is the shear modulus. The bulk modulus is ...


2

I guess you mean to ask - is the amplitude of the vibration proportional to the speed of the sound waves it produces? The speed of sound in an ideal gas for relatively small amplitudes ($\frac{\Delta P}{P} \ll 1$) is $v=\sqrt{\frac{\gamma P}{\rho}}$ where $\gamma$ is the adiabatic constant (i.e. $PV^\gamma=const$), P is the average pressure, and $\rho$ is ...


0

Volume is not strict word for describing sound (look, how many meanings in acoustics it has) http://en.wikipedia.org/wiki/Volume_%28disambiguation%29 "Loud" sounds are basically those of big amplitude. And amplitude of wave and its speed are two different things that have not much in common. Hitting a plank harder will make louder sound (the plank will ...


0

In the context of this specific video, I believe that you cannot truly have a perfect square plate no matter how good your tools are. Therefore the pattern actually does settle on a specific frequency and not at two different frequencies.


3

If the bell is still vibrating when you let air inside it, then the answer is yes. If the bell was damped just before the door is opened, then the answer is no. Sound is transmitted through compression / decompression waves (pressure waves) in a medium (e.g. air, water, wall). This necessitates contact of the vibrating source of sound with such a medium. ...


0

Much of what you ask is covered in the question Demonstration that vibrating basic particles constitute non-vibrating individuals. The vibration is imperceptible to the eye so the object wouldn't look different. However you ask: Also, would this type of vibration cause any negative effects to the object? Yes, indeed it would. The vibration you ...



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