Questions tagged [acoustics]
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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Optimizing sensor for sensitivity, but not sure about taking into account signal to noise ratio
I have a question regarding sensors.
I am currently trying to use an ultrasound sensor to measure surface roughness and other material properties. This is done by using a reflected signal at an ...
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Propagation of ultrasonic waves in a metallic plate (steel) [closed]
Could you help me model the propagation of an ultrasonic wave in a metal plate at different angles of incidence? (especially in the case of a plate submerged in water)
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How are the purest possible audio tones produced?
A pure tone is an idealized audio signal that is perfectly sinusoidal, with a fixed frequency, amplitude, and phase offset.
No physical electronic speaker, tuning fork, etc. can produce an ideal pure ...
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Can the beat frequency of two slightly different tones cause a room to resonate?
During a choral rehearsal, I was thinking about two acoustic phenomena: acoustic resonance, and beat frequencies. My assumptions about these effects are as follows:
Beat frequencies: when two tones ...
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Why Newton's consideration was wrong, but Laplace's correct? [duplicate]
To calculate speed of sound, Newton considered it isothermal process and Laplace considered it an adiabatic process. Why Newton's consideration of isothermal process was wrong, while Laplace's ...
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High-pitched "dog whistles" exist; what about high-pitched "dog bells"?
Whistles of different shapes make differently pitched sounds. You can shape a whistle so that its pitch is above the range audible to humans; we call this a "dog whistle."
Bells of different ...
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Tension in a vibrating string
My book Advance Acoustics by D.P. Roychaudhury has a part where it derives the velocity of transverse waves along a string. The amplitude of displacement is supposed to be small, and its mentioned:
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Tuning fork frequency – ‘wrong’ frequency? [closed]
I have a tuning fork which is labelled ‘Scientific Pitch: G’. It does not have the frequency I expect it to have. What am I misunderstanding?
‘Scientific pitch’ is C=256Hz, of course, so I'd expect ‘...
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Energy absorbed by a sound trihedral corner reflector
I’m trying to model how much sound wave energy is dissipated in the walls of a corner reflector (three mutually perpendicular flat plates, like a 3D corner cube). Each plate is a square of side length ...
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Supersonic jet in a pipe with subtle diameter change
Consider following scenario. I have a large (treat as infinite) container full of gas. There is a smaller pipe (1) with cross-sectional area $A_1$ that connects to a larger pipe (2) with cross-...
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I thought lighting always makes sounds when it strikes something, am I wrong?
I was recording a storm on video and saw a very bright flash of light right in my backyard that was not attributed to a strike. Curious about what it was, I went back and did slo-mo on it, and it was ...
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Does harmonic vs inharmonic content have a statistical advantage in exciting room modes?
In a rectangular room, the axial standing-wave modes occur at frequencies that are integer multiples of a fundamental: $f_n = n \cdot \frac{c}{2L}$. When excited, the energy in a mode depends on the ...
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Frequency of the sum of two sound waves [closed]
I'm trying to solve the following problem:
A stationary receiver hears two sounds coming from two vehicles moving away. Vehicle A emits a sound at a frequency of 400 Hz and moves away at a speed of ...
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Relationship between sound heard from two different locations
Suppose you're on the second floor of a house, and make a hammering noise. You measure the noise level downstairs from two different rooms, room A and room B, which measure $x_A$ dB and $x_B$ dB, ...
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How best to approximate the average speed that the atmosphere would move into a suddenly-appeared vacuum?
Introduction
This question is one of a 5-part series that I originally introduced in this multi-part question: Questions about the behavior of a void (vacuum) in atmosphere.
The original question was ...
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