In physics, sound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid.
In human physiology and psychology, sound is the reception of such waves and their perception by the brain. Only acoustic waves that have frequencies lying between about 20 Hz and 20 kHz, the audio frequency range, elicit an auditory percept in humans. In air at atmospheric pressure, these represent sound waves with wavelengths of 17 meters (56 ft) to 1.7 centimetres (0.67 in). Sound waves above 20 kHz are known as ultrasound and are not audible to humans. Sound waves below 20 Hz are known as infrasound. Different animal species have varying hearing ranges.
I got these tuning forks from someone.
However, I do not have the resonant box for amplification of the sound. I decided to get it made so that I can experience the fundamental frequency (and other harmonics) more clearly.
I am planning to provide this design.
In summary, the box would be...
There are two blocks of apartments separated by a narrow alleyway. Person 1 is in the middle of the room in Apartment 1 (first floor if you are in the UK and second floor if you are in the USA!) and Person 2 is on the ground outdoors in the alleyway.
If both people speak at the same volume...
##-w1## and ##-w2## are to shift the cosine graph to the right, and ##\frac{2pi}{\lambda}## is to stretch the graph. But I can't seem to draw an appropriate ##y1+y2## graph (quite irregular) and I struggle to find the resultant frequency and wavelength. Also, why is there angular frequency in a...
Imagine you have two identical rooms opposite each other with some space in between. (Ie two rooms across from the passage or two rooms leading off of another room). Sound is being emitted from one room only. Would closing the door in the room where the sound is being emitted from or would...
Two of my pupils in secondary high school is doing a project on the sound generated by striking glass bottles drumsticks.
They fill the bottle partially with water and strike the bottle with a drumstick and record the sound.
Preliminary results:
As long as the water level is in the cylindrical...
My attempt:
p and T allows us to calculate ##Z=402 \frac{kg}{sm^2}## using ## Z=p*\sqrt(\frac{\gamma*M}{R*T})## . The sound intensity level at 10 meters allows us to calculate the intensity at 10 meters to be I=10``````^{-7} W/m^2 using ##50 = 10*log(I/I_0)##. Then, using the formula...
While studying the fundamentals of sound waves in organ pipe, I noted that the fact about phase of reflected waves is contradicting while referring multiple sources
This book of mine describes the reflection from a rigid surface/closed end to be in phase
Whereas this one describes the...
My thought process was this,
They are asking us to find the frequency of sound recieved by observer when the source reaches at origin. According to me when the source reaches origin there would be no component of source's velocity in the direction of observer, hence vs=0
vo=0 since the observer...
I was conducting an experiment with a tone generator (330 Hz) in boxes of different sizes with a glass plate placed on top of the box. There is a receiver about .55 meters away. Without any interference, the receiver registered -41 db +/- 1 db. When the tone generator is placed in the box and...
My neighbor has two AC condensers are driving me insane.
I took measurements of the units, and they were between 33.5db - 47.9db at 80HZ.
About 3 feet away is a cinderblock privacy fence between us. It is about 10 feet tall. His home is on an elevation about 4 feet higher than mine (so the...
I wanted to know what are the ways I can have someone speak normally and the other person in another section hear the sound? (there's no closed rooms but there are mirror partitions occasionally)
So one of the things I thought of was using the whispering gallery phenomenon. To save space and...
The values calculated was nowhere near the theoretical values, though I guessed they won't be as the results recorded was incredibly inaccurate. My teacher acknowledged the fact the final values won't be close to the theoretical ones but also said that my formula was wrong, that it works to find...
I built a guitar (fuzz) effect, and analysed the sine wave from a tone generator through an oscilloscope. Wondering what the wave means and how it got to be the way it is. I will attach a picture of the oscilloscope screen + the circuit I used for the Fuzz effect. My question is what the cause...
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...
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?
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...
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...
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...
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...
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...
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 am not a physics major and dont 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...
Homework Statement
Two identical loudspeakers
are driven in phase by the same amplifier at a frequency of 680 Hz. The
speakers are 4.6 m apart. An observer stands 9 m away
from one of the speakers as shown. The observer
then starts moving directly towards the closest speaker.
How far does the...
Homework Statement .[/B]
For a certain type of steel, stress is always proportional to strain with Young's modulus 20 x 10^10 N/m^2. The steel has density 7.86 x 10^3 kg/m^3. A rod 80.0 cm long, made of this steel, is fired at 12.0 m/s straight at a very hard wall.
a) The speed of a...
Homework Statement
Sorry, it's not an actual problem, it's just a statement I don't understand from my text - "The density of water vapor is less than that of dry air. Therefore, the higher the humidity (that is, the more water vapor there is in the air), the lower the density of the air. For...
If a sound wave hits multiple scatterers spaced closer than the wavelength and moving fast
but at different velocities how is the reflective beam is affected?