Frequency range of sound

The easily accessible frequency range of sound and ultrasound waves confines the range of applicability of... 

Figure 1.1. Frequency ranges of sound and ultrasound. (Reproduced with permission of Wiley-VCH — modified — Ref [8].)...

Low frequency mechanical resonances within elastic protein-based polymers occur near 3 kHz (within the frequency range of sound absorption) and 5 MHz (near radio frequencies). 

Audible sound has a frequency range of approximately 20 Hertz (Hz) to 20 kilohertz (kHz) and the pressure ranges from 20 x 10 N/M to 200 N/M. A pure tone produces the simplest type of wave form, that of a sine wave (Figure 42.1). The average pressure fluctuation is zero, and measurements are thus made in terms of the root mean square (rms) of the pressure variation. For the sine wave the rms is 0.707 times the peak value. 

The sound emitted from methanol boiling on a copper tube at 1 atm. has been measured (W2). No forced convection was used. Figure 10 shows how the sound, in total decibels for the frequency range of 25 to 7500 cycles/sec., varies with the temperature difference. Nucleate boiling... 

The sound transmission through the coal/toluene/benzene slurry was examined in the frequency range of 0.1-1 MHz. Measurements were made by pulsing an AE transducer with a sine tone burst. The tone burst travels through the medium and is received by another AE transducer directly across the pipe. Acoustic emission transducers were chosen for this study because of their flat... 

The most important of fhe above sound sources, typically, are the combustion roar from the combustion process itself, which resides in the frequency range of approximately 100 to 1000 Hz, and the gas jet noise, which typically ranges between 4000 and... 

Anechoic room room whose boundaries effectively absorb all incident sound over the frequency range of interest, thereby creating essentially free field conditions. 

Not all species hear sounds in the same frequency ranges. Indeed, there are some with twice the frequency range of humans. 

Sound consists of mechanical vibrations and waves of an elastic medium. It is produced by a mechanical stimulation ofthe elastic medium. According to the carrier media, one distinguishes gas, liquid or impact sound. Sound can be perceived by the human ear in the frequency range of 16-20 000 Hz. 

As we have seen, defoaming of foams prepared from dilute, low-viscosity, aqueous surfactant solutions has been reported mainly with ultrasound in the frequency range of 20-25.8 kHz. The only reported exception to this concerns the extremely weak effect described by Komarov et al. [60] in the frequency range of 2-7 kHz. If we reasonably ignore the latter, then we can use the plot of the sound velocities for 0.99 < 0.999 shown in Figure 7.21 to estimate the range of wavelengths... 

A microphone was used to measure the laser-induced sound generated by laser irradiation of a sample over a frequency range of 20-70 kHz. The microphone was set at a distance of 10 cm from the sample surface and at an angle of 45° to the surface. Frequency analysis of the generated laser-induced sound was performed using analytical software TDS waveform utility. 

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