Sound Definition and 1000 Threads

What is the mathematics involved with calculating the energy lost from sound as it passes through different mediums? If I started off with a 70dB(A) sound wave, and after 0.5m it passed through 10mm of mild steel - what would be the sound level (in dB) 1m away from the steel plate? To clarify...

Hi,i want to calculate the speed of sound in water Containing Chlorine : 4mg/L in 1L distill Water Chloroamine : 4mg/L in 1L distill Water Florides : 0.5mg/L + in 1L distill Water Copper : 0.005mg/L + in 1L distill Water Lead : 1.3 mg/L in 1L distill Water Can you please help in...

I have a friend who has a film with teleportation in it, and when the people teleport, it makes no sound and doesn't have any effect on the area the teleporter left or arrived at. Since a teleporter leaving a location would create a vacuum the size of their body, and the air would quickly...

In collisions that are inelastic or partially elastic, how can we predict how much of the energy lost to the surroundings becomes heat, and how much becomes sound? What determines that fraction?

Summary:: Can smaller volume sound waves completely cancel out larger volume sound waves, and if not to what degree will the larger sound be canceled out. Hello everyone, just had a question regarding destructive interference. So I am in the process of writing/designing a sci-fi/fantasy power...

But the solution should be ##t_1 = \frac a {v_s - v_2}## I assumed the following - 1. I did not consider the frequency as the Doppler shift in frequency was not asked. 2. I did not add the distance the source moved in time ##t_1## to the total distance traveled by the wave as the pulse was...

I make marimbas, and I have invented a few variations (www.marimbaaustralia.com) I am interested in how sound moves through the wooden bars - in particular the effect that temperature has and how to compensate during tuning on different temperature days. I have almost no algebraic knowledge...

I am stumped analyzing the transmission of sound through a rectangular slot in a thin rigid wall. I have found online that a square or round aperture acts as a highpass filter with a 6dB/oct slope and a corner frequency where the wavelength is on the order of twice the aperture diameter...

This means the sound wave reaches the outlet faster as it travels in the same direction as the medium. But I was reading online that speed of sound is independent of the medium so I don't know why my professor used this approach. If speed of sound was dependent on the medium, then wouldn't shock...

This is the work I've done so far... I=p^2/2dv...I=(10)^2/2(1.2)(343)=.12112 I(A)=P...(.12112)(4pi(500)^2)=380522.366 I=P/A...380522.366/4pi(4000)^2=.0018925 10log(I/I0)...10log(.0018925/10^-12)=92.77db 92.77-7(4)=64.77db I am winging it and that's the closest I can get to the right answer...

The speed of sound in a gas at temperature T is given to be ## v=\sqrt{\frac{\gamma RT}{M}}##, where ##\gamma## is the adiabatic exponent, R is the gas constant and M is the molar mass of the gas. In deriving this expression, we assumed that the compression and expansion processes were so fast...

Summary: how to apply the the changes in frequency one can hear when a church bell is swinging through the air onto other acoustic sounds in a computer? Hello all, new to this forum. For an (art) sound installation I would like to apply the the changes in frequency one can hear when a church...

Two similar speakers are connected to a stereo system that emits a signal of frequency 𝑓. However, the signal to speaker B is inverted so that positive voltage becomes negative (but with the same absolute value) and vice versa for negative voltages that become positive. A sound intensity meter...

I am having trouble understanding the following passage in my physics textbook, particularly the bolded sentence: "The speed of sound in a gas is closely related to the rms speed of the molecules of that gas. In a sound wave, the disturbance is passed from one molecule to another by...

1x10^-6 W/M2 is 60 dB The sound goes through both mediums --> 25dB *2 = 50dB lost Therefore the dound after object is 60dB-50dB = 10dB and converting to intensity it is 1x10-11W/M2 is that it?

I don't really know where to start as this is not exactly my homework and I finished school some 15 years ago. I looked into my old high school notes, the last time I ever had anything about mechanical waves and sound. Unfortunately, we never learned anything about sound waves causing...

100mW = 20 dBm, that is then amplified by 2dB 20dBm/2dB = 10mW so power out of the amplifier would be 100mW+10mW =110mW?

Hi people, So I've been digging into music theory and want to understand the basic reasons for how it is constructed. I've come across a particular relationship but I can't understand the reason it exists. A quick musical lesson: Imagine you've got a pure musical note: let's say C. From a low...

Hi there, I am a guitarist and have recently decided to learn the piano as a tool for learning music theory. In digging into music theory I've come into wanting to understand it from the very physics of sound upwards. You'll probably find me on forums discussing sounds theory mostly! I live in...

I'm not sure! I'm really lost on this problem to be honest.

Hello, First post here. I have some data I am trying to do some forecasting on and was hoping somebody who knows what they're actually doing can verify what I have done. A few years ago, the company I work for developed a mobile app for its customers and about 1 year ago they added some new...

I'm contemplating extending the concept of corner reflectors to wavelengths in the audible spectrum, specifically road noise. I read somewhere that road noise is predominantly between 800 Hz and 1300 Hz. The corresponding wavelengths (at 20°C) are 16.9 inches and 10.4 inches. I read elsewhere...

Summary: Is it the same as Bohm velocity ? Is it the same as Bohm velocity ?

Hi everyone! I honestly wasn't sure where I should put this, but I had recently come across this online article from Scientific American about researchers from NIST and the University of Colorado having developed the ability to trap and gain control of "phonons" (sound "particles", roughly...

Homework Statement: Two identical audio speakers, connected to the same amplifier, produce monochromatic sound waves with a frequency that can be varied between 300 and 600 Hz. The speed of the sound is 340 m/s. You find that, where you are standing, you hear minimum intensity sound a) Explain...

Dear all, "Why do air molecules start to oscillate and influence each other such that a wave is forming when you hit e.g. a drum?" High school students asked me this, thinking the air molecules collide like marbles, creating a longitudinal wave. How would you explain this interaction-wise? Any...

Hi, Once someone wrote the following to me in response to my query. My query was somewhat unrelated to it and I don't even have the copy of query anymore. The pressure felt by the piston at any time is the average component of momentum of a gas molecule that is normal to the piston times the...

When I turn on my water kettle, I hear that familiar "hush" sound as the water heats. What exactly is that? The surface of the water vibrating? Warmer, expanding air leaving the kettle? I know it can't be a function of the water temperature itself because when I turn the kettle off the sound...

There is no sound in space because there are not enough particles to transmit the pressure wave. But what about really high in the atmosphere where there is just a little air? Would sound move faster, slower or at the same speed? Would the intensity (aka volume) go up, down, or stay the same...

Summary: The problem: If one wants to make a digital record of sound such that no audible information is lost, what is the longest interval, Δt, between samples that could be used? ( it gives a hint that humans can hear sound waves in the frequency range 20 Hz to 20 kHz. It should be a very...

I need to develop some kind of simplified formula that will allow me to estimate pitch and volume of a sound of two colliding objects in a simulation. It doesn't have to be exact, mostly it is enough that it follows the intuition - large object produce lower sounds, large and fast object produce...

I've been going round in circle and am stuggling as maths is not my strong suit. Any ideas? Up to the point where i equate the powers and then confuse myself, any help would be greatly appreciated.

There are many fluid dynamics applications such as pipe flows, jet flows, boundary layers where we ignore any sound waves present in the system. I don't understand this though, because all sound waves are caused by pressure disturbances so why can we ignore these pressure disturbances when we...

Hi, I'm trying to model the transmission loss and SNR of an acoustic signal underwater. I'm using this expression to modelize the transmitted signal: y = sqrt(P)*exp(1i*2*fr*pi*t)' where P is the transmission power in watts, fr is the transmission frequency and t is the acquisition time. The...

I don't know in which category this subject belongs to. Anyways, here it is: https://www.sciencealert.com/a-new-study-backs-up-claims-that-sound-waves-really-do-have-mass-after-all?fbclid=IwAR2Cmsxm_Garm0PVn03f4UxVQ8adcK4Il3A_N7bUbJT1KaGR1ZfCbGuWVLE How exactly is this measured? Can we expect...

Hi, First thank you in advance for reading and answering my question. I am very much a newbie when it comes to physics, so while I feel my question in pretty straight forward I'm sure it's more complex than my thinking. OK so here it is... Does the texture of two surfaces change the decibel...

I is proportionate to E. r = 4.3xxm So I put 0.75I The answer is 49mW.. But I got 97.xxmW What is wrong?

Hey! Thought I'd drop by and ask. Something strange happened this morning. I turned on my iPod because I was going to listen to a lecture recording for a class. I could get the voice memo to "play", but absolutely no sound is coming out. I tried it with and without headphones, but no luck at...

I do not understand parts c and d. For part C I have no idea where to start. And for part d, I got 1/4λ = L (open-close tube fundamental harmonics) so λ = 4L. But the answer key says it is 1/2 L. Help!

Hello, I am going to be doing a project in which I'll be looking at how sound waves change the shape of an object. Specifically how sound waves can compress something. My question is, can I approximate a sound wave as a force in this case? I know a sound wave is much more complicated than a...

Since electrical charges causes a sparkle or a crackle which is light and sound. Also light and sound are forms of energy does that mean that electrical discharge releases energy and if yes then the release of energy have an effect on charge

I have some questions about J. S. Bell’s famous theorem as presented in his1964 paper.1 These are about his theoretical assumptions and reasoning, not about experimental observations such as Aspect-type experiments. While some questions relate to the experiments, others do not because Aspect’s...

I have a basic understanding of Huygens principle, but I don't quite understand why sound waves follow huygens principle. When sound travels, particles travel back and fourth in one direction, so how do sound waves end up traveling in all directions after traveling through a slit? Do sound...

Is there any formula for calculating sound power? What does the A mean in I=P/A? Is the power of sound dependent on the area of its surrounding or something. I want to know if there's an equation for P like there's I=2π²a²f²ρv.

I understand that sound is a propagating pressure through a medium. We produced pressure and it’ll propagate through the medium as “sound”. How can we use this model to understand everyday-life experiences like opening a chips packaging and the packaging makes a sound, and alike. In the chips...

d² = 40² + 60² ---> I 60 = V.t ---> II 40 + d = V.(t + 1/8) ---> III Thanks in the advance. :)

Homework Statement https://imgur.com/lGas78X The solution to this question says 450Hz. However, when I attempted to compute the frequency using the wave equation and find the normal mode solutions, I get 750Hz 2. Homework Equations I suspect that the solution could be wrong, is that the...

Hi all, I recently came across an exercise observing that human cannot hear ultrasounds, but could hear the beat between two different ultrasounds, provided that its frequency falls in the audible range between 20 Hz and 20kHz. The problem gives one frequency and asks for the range of the other...

I had to find the phase difference between sound waves created by two sources at different distances from a given point. I found the correct answer to be about 13.4. Would any other answer of the form (13.4 + 2npi) also be correct, assuming n is a non-zero integer? Or is 13.4 the only correct...

I am not a physics major and don't know even where to start trying to interpet this spectrogram from the NIST website of the element Calcium https://physics.nist.gov/PhysRefData/Handbook/Tables/calciumtable2.htm My goal is to find a way of converting this spectrogram into a tone or frequency...