If sound is a longitudinal wave, why can we hear it if our ears aren't aligned with the propagation...
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If a sound wave travels to the right, then the air molecules inside only vibrate left and right, because sound is a longitudinal wave. This is only a one-dimensional motion. If our ears are oriented perpendicular to this oscillation, e.g. if they are pointing straight up, how can we hear it?
waves acoustics
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show 7 more comments
$begingroup$
If a sound wave travels to the right, then the air molecules inside only vibrate left and right, because sound is a longitudinal wave. This is only a one-dimensional motion. If our ears are oriented perpendicular to this oscillation, e.g. if they are pointing straight up, how can we hear it?
waves acoustics
New contributor
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2
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it is not that simple . see hyperphysics.phy-astr.gsu.edu/hbase/Sound/sprop.html and links
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– anna v
2 days ago
2
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This website has some nice animations to show the three dimensional nature of longitudinal sound waves.
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– Farcher
yesterday
2
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Here's another pretty good explanation with animations, courtesy of the University of Southampton.
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– Ilmari Karonen
yesterday
2
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Almost everybody commenting or answering has completely misinterpreted the question. There is no need to rehash the entirety of an introductory course of waves, in 10 little bits and pieces, when the actual question is much more specific.
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– knzhou
19 hours ago
1
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@IlmariKaronen OP replied in several comments below, annoyed that answerers had misinterpreted his question. I just tried to condense them in a more digestable form.
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– knzhou
11 hours ago
|
show 7 more comments
$begingroup$
If a sound wave travels to the right, then the air molecules inside only vibrate left and right, because sound is a longitudinal wave. This is only a one-dimensional motion. If our ears are oriented perpendicular to this oscillation, e.g. if they are pointing straight up, how can we hear it?
waves acoustics
New contributor
$endgroup$
If a sound wave travels to the right, then the air molecules inside only vibrate left and right, because sound is a longitudinal wave. This is only a one-dimensional motion. If our ears are oriented perpendicular to this oscillation, e.g. if they are pointing straight up, how can we hear it?
waves acoustics
waves acoustics
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edited 19 hours ago
knzhou
44.8k11122216
44.8k11122216
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asked 2 days ago
Sarvesh ThiruppathiSarvesh Thiruppathi
786
786
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2
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it is not that simple . see hyperphysics.phy-astr.gsu.edu/hbase/Sound/sprop.html and links
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– anna v
2 days ago
2
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This website has some nice animations to show the three dimensional nature of longitudinal sound waves.
$endgroup$
– Farcher
yesterday
2
$begingroup$
Here's another pretty good explanation with animations, courtesy of the University of Southampton.
$endgroup$
– Ilmari Karonen
yesterday
2
$begingroup$
Almost everybody commenting or answering has completely misinterpreted the question. There is no need to rehash the entirety of an introductory course of waves, in 10 little bits and pieces, when the actual question is much more specific.
$endgroup$
– knzhou
19 hours ago
1
$begingroup$
@IlmariKaronen OP replied in several comments below, annoyed that answerers had misinterpreted his question. I just tried to condense them in a more digestable form.
$endgroup$
– knzhou
11 hours ago
|
show 7 more comments
2
$begingroup$
it is not that simple . see hyperphysics.phy-astr.gsu.edu/hbase/Sound/sprop.html and links
$endgroup$
– anna v
2 days ago
2
$begingroup$
This website has some nice animations to show the three dimensional nature of longitudinal sound waves.
$endgroup$
– Farcher
yesterday
2
$begingroup$
Here's another pretty good explanation with animations, courtesy of the University of Southampton.
$endgroup$
– Ilmari Karonen
yesterday
2
$begingroup$
Almost everybody commenting or answering has completely misinterpreted the question. There is no need to rehash the entirety of an introductory course of waves, in 10 little bits and pieces, when the actual question is much more specific.
$endgroup$
– knzhou
19 hours ago
1
$begingroup$
@IlmariKaronen OP replied in several comments below, annoyed that answerers had misinterpreted his question. I just tried to condense them in a more digestable form.
$endgroup$
– knzhou
11 hours ago
2
2
$begingroup$
it is not that simple . see hyperphysics.phy-astr.gsu.edu/hbase/Sound/sprop.html and links
$endgroup$
– anna v
2 days ago
$begingroup$
it is not that simple . see hyperphysics.phy-astr.gsu.edu/hbase/Sound/sprop.html and links
$endgroup$
– anna v
2 days ago
2
2
$begingroup$
This website has some nice animations to show the three dimensional nature of longitudinal sound waves.
$endgroup$
– Farcher
yesterday
$begingroup$
This website has some nice animations to show the three dimensional nature of longitudinal sound waves.
$endgroup$
– Farcher
yesterday
2
2
$begingroup$
Here's another pretty good explanation with animations, courtesy of the University of Southampton.
$endgroup$
– Ilmari Karonen
yesterday
$begingroup$
Here's another pretty good explanation with animations, courtesy of the University of Southampton.
$endgroup$
– Ilmari Karonen
yesterday
2
2
$begingroup$
Almost everybody commenting or answering has completely misinterpreted the question. There is no need to rehash the entirety of an introductory course of waves, in 10 little bits and pieces, when the actual question is much more specific.
$endgroup$
– knzhou
19 hours ago
$begingroup$
Almost everybody commenting or answering has completely misinterpreted the question. There is no need to rehash the entirety of an introductory course of waves, in 10 little bits and pieces, when the actual question is much more specific.
$endgroup$
– knzhou
19 hours ago
1
1
$begingroup$
@IlmariKaronen OP replied in several comments below, annoyed that answerers had misinterpreted his question. I just tried to condense them in a more digestable form.
$endgroup$
– knzhou
11 hours ago
$begingroup$
@IlmariKaronen OP replied in several comments below, annoyed that answerers had misinterpreted his question. I just tried to condense them in a more digestable form.
$endgroup$
– knzhou
11 hours ago
|
show 7 more comments
8 Answers
8
active
oldest
votes
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vibration is only a one dimensional motion
This is not generally true. As a trivial example, one could the movements of water in a pond where a few small rocks have been tossed. The motion is definitely a wave behavior, and could even be called vibration, but it is most definitely not one dimensional.
Another potential example would be the vibrator on your phone, which vibrates in a circular manner.
But in the end, the key is that atoms in a sound wave don't vibrate "left and right." They are a longitudinal wave, in which particles move in the direction of the wave's motion and back.
So when something causes a sound, the waves propagate outward from the object creating the sound, as molecules of gas move away from the source and towards the source. This is typically a 3 dimensional pattern
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Hi, Thanks for the answer , it was really helpful. I still have doubt in the last paragraph of your answer. Can you explain it with more details. Also I never said that sound wave is a transverse wave , by left and right i meant to - and - fro.
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– Sarvesh Thiruppathi
yesterday
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Also , by 3 dimensional pattern , you mean a spherical kind of pattern , right ? But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre.
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– Sarvesh Thiruppathi
yesterday
1
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@SarveshThiruppathi In a sense, yes, as the particles move apart it creates a low pressure region, but this acts as the restoring force to bring them back together. These pressure variations are usually very small, though. For example, a typical conversation between 2 people generates pressure variations of about 2*10^-7 atmospheres.
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– Kyle
yesterday
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But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop
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– Sarvesh Thiruppathi
yesterday
2
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@SarveshThiruppathi If a sound wave is emitted for a long period of time, that means the source of the sound is vibrating for a long period of time. The wavelength would still be the same as if the same sound were emitted for a short period of time, so the vacuum you're imagining between waves wouldn't exist. What does make a difference is the volume (loudness) of the sound, which is why (roughly) there is a maximum possible volume which is reached when there is a vacuum between each wave.
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– dbmag9
yesterday
|
show 2 more comments
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Sound wave is not a transverse wave, as you thought. That means the vibration and the direction of propagation for sound wave are parallel. And the vibration is caused by difference in air pressure at different places. To the question "how I can listen to it" thats because the pressure difference propagates toward your ear and force your eardrum to vibrate.
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Hi, I would like to point out two things from your answer. I never said a sound is a transverse wave. Also can you provide a explanation of how the sound wave propagated towards us.
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– Sarvesh Thiruppathi
yesterday
2
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Note, sound can be also a transverse wave, but only in solid materials (others don't have a shear stress). It has different properties than the longitudinal sound. This is how the internal properties of the Earth were discovered (liquid mantle, solid core). Also the electromagnetic and gravitational fields propagate as transverse waves.
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– peterh
yesterday
1
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"Sound wave is not a transverse wave, as you thought." This is nowhere in the OP's statement. As far as I'm concerned, this answer doesn't address the question at all.
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– knzhou
19 hours ago
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@knzhou I agree. -1. I'm not sure how this has gotten so many up votes
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– Aaron Stevens
19 hours ago
1
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@user10842694 I edited the question to make it a little clearer, but it was already clear in the first version that he wasn't asking "is sound a transverse wave". It blows my mind how half the answers here have answered that question instead.
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– knzhou
19 hours ago
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show 3 more comments
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Sound travels outwards from a source in all directions. The waves that are set in motion are spherical.
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Yes -- even though a 'speaker' may push air molecules in a certain direction, this just creates a volume of higher pressure air, which then expands in all directions.
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– amI
yesterday
add a comment |
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Re. from one of your comments: "But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre" and also this one: "But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop"
I think part of you confusion comes from this: Even with a longitudinal wave where the particle motion is parallel to the waves propagation direction, the particles do not travel with the wave. They only move back and forth along the direction of wave propagation. So the particles are not carried along with the wave. (It is obvious that this is true for a transverse wave.)
Referring to your original question, unless sound is focused into a beam it generally propagates equally in all directions. If it is focused into a beam and you were off to one side anything you hear would be due to sidelobes which are lower in amplitude than the main lobe and could be near zero.
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add a comment |
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The revised question, as I understand it, amounts to asking how it is possible for a sound wave propagating along (instead of towards) a wall with a small hole in it to generate any sound waves on the other side of the hole. I have drawn a diagram of what I believe happens in this case:
The hole bleeds off some of the acoustic energy of the plane wave, and uses it to generate a circular wave on the other side of the wall, as if it were a point source. This is an example of diffraction. I know for certain that this is what happens when the plane wave propagates toward the hole, and I think in this simple case the angle between the plane wave and the wall would only affect the intensity of the circular wave, but I'm not sure of that and the Wikipedia page on diffraction doesn't say anything about the angle. Can anyone confirm?
(N.B. A human's external ear has a much more complicated shape, which has evolved to efficiently gather sound waves passing the head in any direction and direct them into the ear canal, but the physical mechanism by which it does this is the same.)
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You could use an explosion as a metaphor. The shockwaves "push" the air around in a spherical pattern, which then gets "sucked" back due to the low pressure left behind.
In a sense, soundwaves are just very slow and small shockwaves.
This video shows it really well.
New contributor
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+1 - was going to post an answer explaining it via explosion. But... you might consider taking out "just very slow and small shockwaves" and replacing it with, "smaller, and usually either repeated or patterned shockwaves - a musical note is just small shockwaves in a specific timing pattern." or similar.
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– Kevin
yesterday
add a comment |
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There is more than one way to describe the amplitude of a sound wave. You can describe it as a displacement, in which case it's a vector with units of meters. On the other hand, you can also describe it as a pressure, which is a scalar with SI units of pascals.
It's possible to have a sound sensor whose response is proportional to the displacement, or one whose response is proportional to the pressure. The ear acts like the latter, because the eardrum is a membrane, and the membrane distorts in response to the pressure difference between the inner ear and the outside air. Therefore the ear is not sensitive to the direction in which the wave was propagating (although there are other cues that allow us to infer this for some frequencies, because we have binaural hearing).
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add a comment |
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While the mean air motion of the wave is in one direction (assuming a plane wave), the air molecules actually move in all directions. They are in local thermal equilibrium (due to frequent randomizing collisions), which is what gives meaning to pressure as the basis for modeling acoustics. This random molecular motion in all directions is at speeds of order the speed of sound, hundreds of meters per second.
The mean motion (longitudinal) is an oscillating displacement of micrometers or less for typical sounds, at kilohertz frequencies, corresponding to a speed of millimeters per second at most. It can be much less for faint sounds. The ear is a remarkably sensitive detector!
The ear canal is smaller than the wavelengths of audible sound. Thus, as sound passes by in any direction, the ear mainly responds to the pressure oscillations without regard to the direction of the wave. When a pressure peak surrounds the ear, air is (slightly) pumped into the ear, due to the random motions that equilibrate pressure. When a trough surrounds the ear, air is (slightly) sucked out of the ear. This happens at the frequency of the sound (say a thousand times per second), vibrating the eardrum.
Zwol's answer correctly notes that this can be seen as an instance of diffraction. It is a limit in which the hole is so small that the pressure at any instant is nearly uniform over the hole, so diffraction through the hole is nearly independent of the incident angle.
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add a comment |
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8 Answers
8
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8 Answers
8
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$begingroup$
vibration is only a one dimensional motion
This is not generally true. As a trivial example, one could the movements of water in a pond where a few small rocks have been tossed. The motion is definitely a wave behavior, and could even be called vibration, but it is most definitely not one dimensional.
Another potential example would be the vibrator on your phone, which vibrates in a circular manner.
But in the end, the key is that atoms in a sound wave don't vibrate "left and right." They are a longitudinal wave, in which particles move in the direction of the wave's motion and back.
So when something causes a sound, the waves propagate outward from the object creating the sound, as molecules of gas move away from the source and towards the source. This is typically a 3 dimensional pattern
$endgroup$
$begingroup$
Hi, Thanks for the answer , it was really helpful. I still have doubt in the last paragraph of your answer. Can you explain it with more details. Also I never said that sound wave is a transverse wave , by left and right i meant to - and - fro.
$endgroup$
– Sarvesh Thiruppathi
yesterday
$begingroup$
Also , by 3 dimensional pattern , you mean a spherical kind of pattern , right ? But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre.
$endgroup$
– Sarvesh Thiruppathi
yesterday
1
$begingroup$
@SarveshThiruppathi In a sense, yes, as the particles move apart it creates a low pressure region, but this acts as the restoring force to bring them back together. These pressure variations are usually very small, though. For example, a typical conversation between 2 people generates pressure variations of about 2*10^-7 atmospheres.
$endgroup$
– Kyle
yesterday
$begingroup$
But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop
$endgroup$
– Sarvesh Thiruppathi
yesterday
2
$begingroup$
@SarveshThiruppathi If a sound wave is emitted for a long period of time, that means the source of the sound is vibrating for a long period of time. The wavelength would still be the same as if the same sound were emitted for a short period of time, so the vacuum you're imagining between waves wouldn't exist. What does make a difference is the volume (loudness) of the sound, which is why (roughly) there is a maximum possible volume which is reached when there is a vacuum between each wave.
$endgroup$
– dbmag9
yesterday
|
show 2 more comments
$begingroup$
vibration is only a one dimensional motion
This is not generally true. As a trivial example, one could the movements of water in a pond where a few small rocks have been tossed. The motion is definitely a wave behavior, and could even be called vibration, but it is most definitely not one dimensional.
Another potential example would be the vibrator on your phone, which vibrates in a circular manner.
But in the end, the key is that atoms in a sound wave don't vibrate "left and right." They are a longitudinal wave, in which particles move in the direction of the wave's motion and back.
So when something causes a sound, the waves propagate outward from the object creating the sound, as molecules of gas move away from the source and towards the source. This is typically a 3 dimensional pattern
$endgroup$
$begingroup$
Hi, Thanks for the answer , it was really helpful. I still have doubt in the last paragraph of your answer. Can you explain it with more details. Also I never said that sound wave is a transverse wave , by left and right i meant to - and - fro.
$endgroup$
– Sarvesh Thiruppathi
yesterday
$begingroup$
Also , by 3 dimensional pattern , you mean a spherical kind of pattern , right ? But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre.
$endgroup$
– Sarvesh Thiruppathi
yesterday
1
$begingroup$
@SarveshThiruppathi In a sense, yes, as the particles move apart it creates a low pressure region, but this acts as the restoring force to bring them back together. These pressure variations are usually very small, though. For example, a typical conversation between 2 people generates pressure variations of about 2*10^-7 atmospheres.
$endgroup$
– Kyle
yesterday
$begingroup$
But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop
$endgroup$
– Sarvesh Thiruppathi
yesterday
2
$begingroup$
@SarveshThiruppathi If a sound wave is emitted for a long period of time, that means the source of the sound is vibrating for a long period of time. The wavelength would still be the same as if the same sound were emitted for a short period of time, so the vacuum you're imagining between waves wouldn't exist. What does make a difference is the volume (loudness) of the sound, which is why (roughly) there is a maximum possible volume which is reached when there is a vacuum between each wave.
$endgroup$
– dbmag9
yesterday
|
show 2 more comments
$begingroup$
vibration is only a one dimensional motion
This is not generally true. As a trivial example, one could the movements of water in a pond where a few small rocks have been tossed. The motion is definitely a wave behavior, and could even be called vibration, but it is most definitely not one dimensional.
Another potential example would be the vibrator on your phone, which vibrates in a circular manner.
But in the end, the key is that atoms in a sound wave don't vibrate "left and right." They are a longitudinal wave, in which particles move in the direction of the wave's motion and back.
So when something causes a sound, the waves propagate outward from the object creating the sound, as molecules of gas move away from the source and towards the source. This is typically a 3 dimensional pattern
$endgroup$
vibration is only a one dimensional motion
This is not generally true. As a trivial example, one could the movements of water in a pond where a few small rocks have been tossed. The motion is definitely a wave behavior, and could even be called vibration, but it is most definitely not one dimensional.
Another potential example would be the vibrator on your phone, which vibrates in a circular manner.
But in the end, the key is that atoms in a sound wave don't vibrate "left and right." They are a longitudinal wave, in which particles move in the direction of the wave's motion and back.
So when something causes a sound, the waves propagate outward from the object creating the sound, as molecules of gas move away from the source and towards the source. This is typically a 3 dimensional pattern
answered 2 days ago
Cort AmmonCort Ammon
23.6k34779
23.6k34779
$begingroup$
Hi, Thanks for the answer , it was really helpful. I still have doubt in the last paragraph of your answer. Can you explain it with more details. Also I never said that sound wave is a transverse wave , by left and right i meant to - and - fro.
$endgroup$
– Sarvesh Thiruppathi
yesterday
$begingroup$
Also , by 3 dimensional pattern , you mean a spherical kind of pattern , right ? But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre.
$endgroup$
– Sarvesh Thiruppathi
yesterday
1
$begingroup$
@SarveshThiruppathi In a sense, yes, as the particles move apart it creates a low pressure region, but this acts as the restoring force to bring them back together. These pressure variations are usually very small, though. For example, a typical conversation between 2 people generates pressure variations of about 2*10^-7 atmospheres.
$endgroup$
– Kyle
yesterday
$begingroup$
But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop
$endgroup$
– Sarvesh Thiruppathi
yesterday
2
$begingroup$
@SarveshThiruppathi If a sound wave is emitted for a long period of time, that means the source of the sound is vibrating for a long period of time. The wavelength would still be the same as if the same sound were emitted for a short period of time, so the vacuum you're imagining between waves wouldn't exist. What does make a difference is the volume (loudness) of the sound, which is why (roughly) there is a maximum possible volume which is reached when there is a vacuum between each wave.
$endgroup$
– dbmag9
yesterday
|
show 2 more comments
$begingroup$
Hi, Thanks for the answer , it was really helpful. I still have doubt in the last paragraph of your answer. Can you explain it with more details. Also I never said that sound wave is a transverse wave , by left and right i meant to - and - fro.
$endgroup$
– Sarvesh Thiruppathi
yesterday
$begingroup$
Also , by 3 dimensional pattern , you mean a spherical kind of pattern , right ? But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre.
$endgroup$
– Sarvesh Thiruppathi
yesterday
1
$begingroup$
@SarveshThiruppathi In a sense, yes, as the particles move apart it creates a low pressure region, but this acts as the restoring force to bring them back together. These pressure variations are usually very small, though. For example, a typical conversation between 2 people generates pressure variations of about 2*10^-7 atmospheres.
$endgroup$
– Kyle
yesterday
$begingroup$
But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop
$endgroup$
– Sarvesh Thiruppathi
yesterday
2
$begingroup$
@SarveshThiruppathi If a sound wave is emitted for a long period of time, that means the source of the sound is vibrating for a long period of time. The wavelength would still be the same as if the same sound were emitted for a short period of time, so the vacuum you're imagining between waves wouldn't exist. What does make a difference is the volume (loudness) of the sound, which is why (roughly) there is a maximum possible volume which is reached when there is a vacuum between each wave.
$endgroup$
– dbmag9
yesterday
$begingroup$
Hi, Thanks for the answer , it was really helpful. I still have doubt in the last paragraph of your answer. Can you explain it with more details. Also I never said that sound wave is a transverse wave , by left and right i meant to - and - fro.
$endgroup$
– Sarvesh Thiruppathi
yesterday
$begingroup$
Hi, Thanks for the answer , it was really helpful. I still have doubt in the last paragraph of your answer. Can you explain it with more details. Also I never said that sound wave is a transverse wave , by left and right i meant to - and - fro.
$endgroup$
– Sarvesh Thiruppathi
yesterday
$begingroup$
Also , by 3 dimensional pattern , you mean a spherical kind of pattern , right ? But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre.
$endgroup$
– Sarvesh Thiruppathi
yesterday
$begingroup$
Also , by 3 dimensional pattern , you mean a spherical kind of pattern , right ? But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre.
$endgroup$
– Sarvesh Thiruppathi
yesterday
1
1
$begingroup$
@SarveshThiruppathi In a sense, yes, as the particles move apart it creates a low pressure region, but this acts as the restoring force to bring them back together. These pressure variations are usually very small, though. For example, a typical conversation between 2 people generates pressure variations of about 2*10^-7 atmospheres.
$endgroup$
– Kyle
yesterday
$begingroup$
@SarveshThiruppathi In a sense, yes, as the particles move apart it creates a low pressure region, but this acts as the restoring force to bring them back together. These pressure variations are usually very small, though. For example, a typical conversation between 2 people generates pressure variations of about 2*10^-7 atmospheres.
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– Kyle
yesterday
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But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop
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– Sarvesh Thiruppathi
yesterday
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But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop
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– Sarvesh Thiruppathi
yesterday
2
2
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@SarveshThiruppathi If a sound wave is emitted for a long period of time, that means the source of the sound is vibrating for a long period of time. The wavelength would still be the same as if the same sound were emitted for a short period of time, so the vacuum you're imagining between waves wouldn't exist. What does make a difference is the volume (loudness) of the sound, which is why (roughly) there is a maximum possible volume which is reached when there is a vacuum between each wave.
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– dbmag9
yesterday
$begingroup$
@SarveshThiruppathi If a sound wave is emitted for a long period of time, that means the source of the sound is vibrating for a long period of time. The wavelength would still be the same as if the same sound were emitted for a short period of time, so the vacuum you're imagining between waves wouldn't exist. What does make a difference is the volume (loudness) of the sound, which is why (roughly) there is a maximum possible volume which is reached when there is a vacuum between each wave.
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– dbmag9
yesterday
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show 2 more comments
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Sound wave is not a transverse wave, as you thought. That means the vibration and the direction of propagation for sound wave are parallel. And the vibration is caused by difference in air pressure at different places. To the question "how I can listen to it" thats because the pressure difference propagates toward your ear and force your eardrum to vibrate.
New contributor
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1
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Hi, I would like to point out two things from your answer. I never said a sound is a transverse wave. Also can you provide a explanation of how the sound wave propagated towards us.
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– Sarvesh Thiruppathi
yesterday
2
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Note, sound can be also a transverse wave, but only in solid materials (others don't have a shear stress). It has different properties than the longitudinal sound. This is how the internal properties of the Earth were discovered (liquid mantle, solid core). Also the electromagnetic and gravitational fields propagate as transverse waves.
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– peterh
yesterday
1
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"Sound wave is not a transverse wave, as you thought." This is nowhere in the OP's statement. As far as I'm concerned, this answer doesn't address the question at all.
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– knzhou
19 hours ago
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@knzhou I agree. -1. I'm not sure how this has gotten so many up votes
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– Aaron Stevens
19 hours ago
1
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@user10842694 I edited the question to make it a little clearer, but it was already clear in the first version that he wasn't asking "is sound a transverse wave". It blows my mind how half the answers here have answered that question instead.
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– knzhou
19 hours ago
|
show 3 more comments
$begingroup$
Sound wave is not a transverse wave, as you thought. That means the vibration and the direction of propagation for sound wave are parallel. And the vibration is caused by difference in air pressure at different places. To the question "how I can listen to it" thats because the pressure difference propagates toward your ear and force your eardrum to vibrate.
New contributor
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1
$begingroup$
Hi, I would like to point out two things from your answer. I never said a sound is a transverse wave. Also can you provide a explanation of how the sound wave propagated towards us.
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– Sarvesh Thiruppathi
yesterday
2
$begingroup$
Note, sound can be also a transverse wave, but only in solid materials (others don't have a shear stress). It has different properties than the longitudinal sound. This is how the internal properties of the Earth were discovered (liquid mantle, solid core). Also the electromagnetic and gravitational fields propagate as transverse waves.
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– peterh
yesterday
1
$begingroup$
"Sound wave is not a transverse wave, as you thought." This is nowhere in the OP's statement. As far as I'm concerned, this answer doesn't address the question at all.
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– knzhou
19 hours ago
$begingroup$
@knzhou I agree. -1. I'm not sure how this has gotten so many up votes
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– Aaron Stevens
19 hours ago
1
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@user10842694 I edited the question to make it a little clearer, but it was already clear in the first version that he wasn't asking "is sound a transverse wave". It blows my mind how half the answers here have answered that question instead.
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– knzhou
19 hours ago
|
show 3 more comments
$begingroup$
Sound wave is not a transverse wave, as you thought. That means the vibration and the direction of propagation for sound wave are parallel. And the vibration is caused by difference in air pressure at different places. To the question "how I can listen to it" thats because the pressure difference propagates toward your ear and force your eardrum to vibrate.
New contributor
$endgroup$
Sound wave is not a transverse wave, as you thought. That means the vibration and the direction of propagation for sound wave are parallel. And the vibration is caused by difference in air pressure at different places. To the question "how I can listen to it" thats because the pressure difference propagates toward your ear and force your eardrum to vibrate.
New contributor
New contributor
answered 2 days ago
user10842694user10842694
1152
1152
New contributor
New contributor
1
$begingroup$
Hi, I would like to point out two things from your answer. I never said a sound is a transverse wave. Also can you provide a explanation of how the sound wave propagated towards us.
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– Sarvesh Thiruppathi
yesterday
2
$begingroup$
Note, sound can be also a transverse wave, but only in solid materials (others don't have a shear stress). It has different properties than the longitudinal sound. This is how the internal properties of the Earth were discovered (liquid mantle, solid core). Also the electromagnetic and gravitational fields propagate as transverse waves.
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– peterh
yesterday
1
$begingroup$
"Sound wave is not a transverse wave, as you thought." This is nowhere in the OP's statement. As far as I'm concerned, this answer doesn't address the question at all.
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– knzhou
19 hours ago
$begingroup$
@knzhou I agree. -1. I'm not sure how this has gotten so many up votes
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– Aaron Stevens
19 hours ago
1
$begingroup$
@user10842694 I edited the question to make it a little clearer, but it was already clear in the first version that he wasn't asking "is sound a transverse wave". It blows my mind how half the answers here have answered that question instead.
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– knzhou
19 hours ago
|
show 3 more comments
1
$begingroup$
Hi, I would like to point out two things from your answer. I never said a sound is a transverse wave. Also can you provide a explanation of how the sound wave propagated towards us.
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– Sarvesh Thiruppathi
yesterday
2
$begingroup$
Note, sound can be also a transverse wave, but only in solid materials (others don't have a shear stress). It has different properties than the longitudinal sound. This is how the internal properties of the Earth were discovered (liquid mantle, solid core). Also the electromagnetic and gravitational fields propagate as transverse waves.
$endgroup$
– peterh
yesterday
1
$begingroup$
"Sound wave is not a transverse wave, as you thought." This is nowhere in the OP's statement. As far as I'm concerned, this answer doesn't address the question at all.
$endgroup$
– knzhou
19 hours ago
$begingroup$
@knzhou I agree. -1. I'm not sure how this has gotten so many up votes
$endgroup$
– Aaron Stevens
19 hours ago
1
$begingroup$
@user10842694 I edited the question to make it a little clearer, but it was already clear in the first version that he wasn't asking "is sound a transverse wave". It blows my mind how half the answers here have answered that question instead.
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– knzhou
19 hours ago
1
1
$begingroup$
Hi, I would like to point out two things from your answer. I never said a sound is a transverse wave. Also can you provide a explanation of how the sound wave propagated towards us.
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– Sarvesh Thiruppathi
yesterday
$begingroup$
Hi, I would like to point out two things from your answer. I never said a sound is a transverse wave. Also can you provide a explanation of how the sound wave propagated towards us.
$endgroup$
– Sarvesh Thiruppathi
yesterday
2
2
$begingroup$
Note, sound can be also a transverse wave, but only in solid materials (others don't have a shear stress). It has different properties than the longitudinal sound. This is how the internal properties of the Earth were discovered (liquid mantle, solid core). Also the electromagnetic and gravitational fields propagate as transverse waves.
$endgroup$
– peterh
yesterday
$begingroup$
Note, sound can be also a transverse wave, but only in solid materials (others don't have a shear stress). It has different properties than the longitudinal sound. This is how the internal properties of the Earth were discovered (liquid mantle, solid core). Also the electromagnetic and gravitational fields propagate as transverse waves.
$endgroup$
– peterh
yesterday
1
1
$begingroup$
"Sound wave is not a transverse wave, as you thought." This is nowhere in the OP's statement. As far as I'm concerned, this answer doesn't address the question at all.
$endgroup$
– knzhou
19 hours ago
$begingroup$
"Sound wave is not a transverse wave, as you thought." This is nowhere in the OP's statement. As far as I'm concerned, this answer doesn't address the question at all.
$endgroup$
– knzhou
19 hours ago
$begingroup$
@knzhou I agree. -1. I'm not sure how this has gotten so many up votes
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– Aaron Stevens
19 hours ago
$begingroup$
@knzhou I agree. -1. I'm not sure how this has gotten so many up votes
$endgroup$
– Aaron Stevens
19 hours ago
1
1
$begingroup$
@user10842694 I edited the question to make it a little clearer, but it was already clear in the first version that he wasn't asking "is sound a transverse wave". It blows my mind how half the answers here have answered that question instead.
$endgroup$
– knzhou
19 hours ago
$begingroup$
@user10842694 I edited the question to make it a little clearer, but it was already clear in the first version that he wasn't asking "is sound a transverse wave". It blows my mind how half the answers here have answered that question instead.
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– knzhou
19 hours ago
|
show 3 more comments
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Sound travels outwards from a source in all directions. The waves that are set in motion are spherical.
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2
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Yes -- even though a 'speaker' may push air molecules in a certain direction, this just creates a volume of higher pressure air, which then expands in all directions.
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– amI
yesterday
add a comment |
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Sound travels outwards from a source in all directions. The waves that are set in motion are spherical.
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2
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Yes -- even though a 'speaker' may push air molecules in a certain direction, this just creates a volume of higher pressure air, which then expands in all directions.
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– amI
yesterday
add a comment |
$begingroup$
Sound travels outwards from a source in all directions. The waves that are set in motion are spherical.
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Sound travels outwards from a source in all directions. The waves that are set in motion are spherical.
answered 2 days ago
niels nielsenniels nielsen
20.4k53061
20.4k53061
2
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Yes -- even though a 'speaker' may push air molecules in a certain direction, this just creates a volume of higher pressure air, which then expands in all directions.
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– amI
yesterday
add a comment |
2
$begingroup$
Yes -- even though a 'speaker' may push air molecules in a certain direction, this just creates a volume of higher pressure air, which then expands in all directions.
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– amI
yesterday
2
2
$begingroup$
Yes -- even though a 'speaker' may push air molecules in a certain direction, this just creates a volume of higher pressure air, which then expands in all directions.
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– amI
yesterday
$begingroup$
Yes -- even though a 'speaker' may push air molecules in a certain direction, this just creates a volume of higher pressure air, which then expands in all directions.
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– amI
yesterday
add a comment |
$begingroup$
Re. from one of your comments: "But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre" and also this one: "But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop"
I think part of you confusion comes from this: Even with a longitudinal wave where the particle motion is parallel to the waves propagation direction, the particles do not travel with the wave. They only move back and forth along the direction of wave propagation. So the particles are not carried along with the wave. (It is obvious that this is true for a transverse wave.)
Referring to your original question, unless sound is focused into a beam it generally propagates equally in all directions. If it is focused into a beam and you were off to one side anything you hear would be due to sidelobes which are lower in amplitude than the main lobe and could be near zero.
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add a comment |
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Re. from one of your comments: "But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre" and also this one: "But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop"
I think part of you confusion comes from this: Even with a longitudinal wave where the particle motion is parallel to the waves propagation direction, the particles do not travel with the wave. They only move back and forth along the direction of wave propagation. So the particles are not carried along with the wave. (It is obvious that this is true for a transverse wave.)
Referring to your original question, unless sound is focused into a beam it generally propagates equally in all directions. If it is focused into a beam and you were off to one side anything you hear would be due to sidelobes which are lower in amplitude than the main lobe and could be near zero.
$endgroup$
add a comment |
$begingroup$
Re. from one of your comments: "But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre" and also this one: "But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop"
I think part of you confusion comes from this: Even with a longitudinal wave where the particle motion is parallel to the waves propagation direction, the particles do not travel with the wave. They only move back and forth along the direction of wave propagation. So the particles are not carried along with the wave. (It is obvious that this is true for a transverse wave.)
Referring to your original question, unless sound is focused into a beam it generally propagates equally in all directions. If it is focused into a beam and you were off to one side anything you hear would be due to sidelobes which are lower in amplitude than the main lobe and could be near zero.
$endgroup$
Re. from one of your comments: "But when the air molecule from the centre keeps moving away ,won't there be a vacuum created at the centre" and also this one: "But if the sound wave is emitted for long periods, wouldn't there be a complete vacuum and the sound wave would stop"
I think part of you confusion comes from this: Even with a longitudinal wave where the particle motion is parallel to the waves propagation direction, the particles do not travel with the wave. They only move back and forth along the direction of wave propagation. So the particles are not carried along with the wave. (It is obvious that this is true for a transverse wave.)
Referring to your original question, unless sound is focused into a beam it generally propagates equally in all directions. If it is focused into a beam and you were off to one side anything you hear would be due to sidelobes which are lower in amplitude than the main lobe and could be near zero.
answered yesterday
user45664user45664
1,3152825
1,3152825
add a comment |
add a comment |
$begingroup$
The revised question, as I understand it, amounts to asking how it is possible for a sound wave propagating along (instead of towards) a wall with a small hole in it to generate any sound waves on the other side of the hole. I have drawn a diagram of what I believe happens in this case:
The hole bleeds off some of the acoustic energy of the plane wave, and uses it to generate a circular wave on the other side of the wall, as if it were a point source. This is an example of diffraction. I know for certain that this is what happens when the plane wave propagates toward the hole, and I think in this simple case the angle between the plane wave and the wall would only affect the intensity of the circular wave, but I'm not sure of that and the Wikipedia page on diffraction doesn't say anything about the angle. Can anyone confirm?
(N.B. A human's external ear has a much more complicated shape, which has evolved to efficiently gather sound waves passing the head in any direction and direct them into the ear canal, but the physical mechanism by which it does this is the same.)
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add a comment |
$begingroup$
The revised question, as I understand it, amounts to asking how it is possible for a sound wave propagating along (instead of towards) a wall with a small hole in it to generate any sound waves on the other side of the hole. I have drawn a diagram of what I believe happens in this case:
The hole bleeds off some of the acoustic energy of the plane wave, and uses it to generate a circular wave on the other side of the wall, as if it were a point source. This is an example of diffraction. I know for certain that this is what happens when the plane wave propagates toward the hole, and I think in this simple case the angle between the plane wave and the wall would only affect the intensity of the circular wave, but I'm not sure of that and the Wikipedia page on diffraction doesn't say anything about the angle. Can anyone confirm?
(N.B. A human's external ear has a much more complicated shape, which has evolved to efficiently gather sound waves passing the head in any direction and direct them into the ear canal, but the physical mechanism by which it does this is the same.)
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add a comment |
$begingroup$
The revised question, as I understand it, amounts to asking how it is possible for a sound wave propagating along (instead of towards) a wall with a small hole in it to generate any sound waves on the other side of the hole. I have drawn a diagram of what I believe happens in this case:
The hole bleeds off some of the acoustic energy of the plane wave, and uses it to generate a circular wave on the other side of the wall, as if it were a point source. This is an example of diffraction. I know for certain that this is what happens when the plane wave propagates toward the hole, and I think in this simple case the angle between the plane wave and the wall would only affect the intensity of the circular wave, but I'm not sure of that and the Wikipedia page on diffraction doesn't say anything about the angle. Can anyone confirm?
(N.B. A human's external ear has a much more complicated shape, which has evolved to efficiently gather sound waves passing the head in any direction and direct them into the ear canal, but the physical mechanism by which it does this is the same.)
$endgroup$
The revised question, as I understand it, amounts to asking how it is possible for a sound wave propagating along (instead of towards) a wall with a small hole in it to generate any sound waves on the other side of the hole. I have drawn a diagram of what I believe happens in this case:
The hole bleeds off some of the acoustic energy of the plane wave, and uses it to generate a circular wave on the other side of the wall, as if it were a point source. This is an example of diffraction. I know for certain that this is what happens when the plane wave propagates toward the hole, and I think in this simple case the angle between the plane wave and the wall would only affect the intensity of the circular wave, but I'm not sure of that and the Wikipedia page on diffraction doesn't say anything about the angle. Can anyone confirm?
(N.B. A human's external ear has a much more complicated shape, which has evolved to efficiently gather sound waves passing the head in any direction and direct them into the ear canal, but the physical mechanism by which it does this is the same.)
answered 13 hours ago
zwolzwol
959615
959615
add a comment |
add a comment |
$begingroup$
You could use an explosion as a metaphor. The shockwaves "push" the air around in a spherical pattern, which then gets "sucked" back due to the low pressure left behind.
In a sense, soundwaves are just very slow and small shockwaves.
This video shows it really well.
New contributor
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+1 - was going to post an answer explaining it via explosion. But... you might consider taking out "just very slow and small shockwaves" and replacing it with, "smaller, and usually either repeated or patterned shockwaves - a musical note is just small shockwaves in a specific timing pattern." or similar.
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– Kevin
yesterday
add a comment |
$begingroup$
You could use an explosion as a metaphor. The shockwaves "push" the air around in a spherical pattern, which then gets "sucked" back due to the low pressure left behind.
In a sense, soundwaves are just very slow and small shockwaves.
This video shows it really well.
New contributor
$endgroup$
$begingroup$
+1 - was going to post an answer explaining it via explosion. But... you might consider taking out "just very slow and small shockwaves" and replacing it with, "smaller, and usually either repeated or patterned shockwaves - a musical note is just small shockwaves in a specific timing pattern." or similar.
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– Kevin
yesterday
add a comment |
$begingroup$
You could use an explosion as a metaphor. The shockwaves "push" the air around in a spherical pattern, which then gets "sucked" back due to the low pressure left behind.
In a sense, soundwaves are just very slow and small shockwaves.
This video shows it really well.
New contributor
$endgroup$
You could use an explosion as a metaphor. The shockwaves "push" the air around in a spherical pattern, which then gets "sucked" back due to the low pressure left behind.
In a sense, soundwaves are just very slow and small shockwaves.
This video shows it really well.
New contributor
New contributor
answered yesterday
DanielDaniel
211
211
New contributor
New contributor
$begingroup$
+1 - was going to post an answer explaining it via explosion. But... you might consider taking out "just very slow and small shockwaves" and replacing it with, "smaller, and usually either repeated or patterned shockwaves - a musical note is just small shockwaves in a specific timing pattern." or similar.
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– Kevin
yesterday
add a comment |
$begingroup$
+1 - was going to post an answer explaining it via explosion. But... you might consider taking out "just very slow and small shockwaves" and replacing it with, "smaller, and usually either repeated or patterned shockwaves - a musical note is just small shockwaves in a specific timing pattern." or similar.
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– Kevin
yesterday
$begingroup$
+1 - was going to post an answer explaining it via explosion. But... you might consider taking out "just very slow and small shockwaves" and replacing it with, "smaller, and usually either repeated or patterned shockwaves - a musical note is just small shockwaves in a specific timing pattern." or similar.
$endgroup$
– Kevin
yesterday
$begingroup$
+1 - was going to post an answer explaining it via explosion. But... you might consider taking out "just very slow and small shockwaves" and replacing it with, "smaller, and usually either repeated or patterned shockwaves - a musical note is just small shockwaves in a specific timing pattern." or similar.
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– Kevin
yesterday
add a comment |
$begingroup$
There is more than one way to describe the amplitude of a sound wave. You can describe it as a displacement, in which case it's a vector with units of meters. On the other hand, you can also describe it as a pressure, which is a scalar with SI units of pascals.
It's possible to have a sound sensor whose response is proportional to the displacement, or one whose response is proportional to the pressure. The ear acts like the latter, because the eardrum is a membrane, and the membrane distorts in response to the pressure difference between the inner ear and the outside air. Therefore the ear is not sensitive to the direction in which the wave was propagating (although there are other cues that allow us to infer this for some frequencies, because we have binaural hearing).
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add a comment |
$begingroup$
There is more than one way to describe the amplitude of a sound wave. You can describe it as a displacement, in which case it's a vector with units of meters. On the other hand, you can also describe it as a pressure, which is a scalar with SI units of pascals.
It's possible to have a sound sensor whose response is proportional to the displacement, or one whose response is proportional to the pressure. The ear acts like the latter, because the eardrum is a membrane, and the membrane distorts in response to the pressure difference between the inner ear and the outside air. Therefore the ear is not sensitive to the direction in which the wave was propagating (although there are other cues that allow us to infer this for some frequencies, because we have binaural hearing).
$endgroup$
add a comment |
$begingroup$
There is more than one way to describe the amplitude of a sound wave. You can describe it as a displacement, in which case it's a vector with units of meters. On the other hand, you can also describe it as a pressure, which is a scalar with SI units of pascals.
It's possible to have a sound sensor whose response is proportional to the displacement, or one whose response is proportional to the pressure. The ear acts like the latter, because the eardrum is a membrane, and the membrane distorts in response to the pressure difference between the inner ear and the outside air. Therefore the ear is not sensitive to the direction in which the wave was propagating (although there are other cues that allow us to infer this for some frequencies, because we have binaural hearing).
$endgroup$
There is more than one way to describe the amplitude of a sound wave. You can describe it as a displacement, in which case it's a vector with units of meters. On the other hand, you can also describe it as a pressure, which is a scalar with SI units of pascals.
It's possible to have a sound sensor whose response is proportional to the displacement, or one whose response is proportional to the pressure. The ear acts like the latter, because the eardrum is a membrane, and the membrane distorts in response to the pressure difference between the inner ear and the outside air. Therefore the ear is not sensitive to the direction in which the wave was propagating (although there are other cues that allow us to infer this for some frequencies, because we have binaural hearing).
answered 11 hours ago
Ben CrowellBen Crowell
52.6k6162306
52.6k6162306
add a comment |
add a comment |
$begingroup$
While the mean air motion of the wave is in one direction (assuming a plane wave), the air molecules actually move in all directions. They are in local thermal equilibrium (due to frequent randomizing collisions), which is what gives meaning to pressure as the basis for modeling acoustics. This random molecular motion in all directions is at speeds of order the speed of sound, hundreds of meters per second.
The mean motion (longitudinal) is an oscillating displacement of micrometers or less for typical sounds, at kilohertz frequencies, corresponding to a speed of millimeters per second at most. It can be much less for faint sounds. The ear is a remarkably sensitive detector!
The ear canal is smaller than the wavelengths of audible sound. Thus, as sound passes by in any direction, the ear mainly responds to the pressure oscillations without regard to the direction of the wave. When a pressure peak surrounds the ear, air is (slightly) pumped into the ear, due to the random motions that equilibrate pressure. When a trough surrounds the ear, air is (slightly) sucked out of the ear. This happens at the frequency of the sound (say a thousand times per second), vibrating the eardrum.
Zwol's answer correctly notes that this can be seen as an instance of diffraction. It is a limit in which the hole is so small that the pressure at any instant is nearly uniform over the hole, so diffraction through the hole is nearly independent of the incident angle.
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add a comment |
$begingroup$
While the mean air motion of the wave is in one direction (assuming a plane wave), the air molecules actually move in all directions. They are in local thermal equilibrium (due to frequent randomizing collisions), which is what gives meaning to pressure as the basis for modeling acoustics. This random molecular motion in all directions is at speeds of order the speed of sound, hundreds of meters per second.
The mean motion (longitudinal) is an oscillating displacement of micrometers or less for typical sounds, at kilohertz frequencies, corresponding to a speed of millimeters per second at most. It can be much less for faint sounds. The ear is a remarkably sensitive detector!
The ear canal is smaller than the wavelengths of audible sound. Thus, as sound passes by in any direction, the ear mainly responds to the pressure oscillations without regard to the direction of the wave. When a pressure peak surrounds the ear, air is (slightly) pumped into the ear, due to the random motions that equilibrate pressure. When a trough surrounds the ear, air is (slightly) sucked out of the ear. This happens at the frequency of the sound (say a thousand times per second), vibrating the eardrum.
Zwol's answer correctly notes that this can be seen as an instance of diffraction. It is a limit in which the hole is so small that the pressure at any instant is nearly uniform over the hole, so diffraction through the hole is nearly independent of the incident angle.
$endgroup$
add a comment |
$begingroup$
While the mean air motion of the wave is in one direction (assuming a plane wave), the air molecules actually move in all directions. They are in local thermal equilibrium (due to frequent randomizing collisions), which is what gives meaning to pressure as the basis for modeling acoustics. This random molecular motion in all directions is at speeds of order the speed of sound, hundreds of meters per second.
The mean motion (longitudinal) is an oscillating displacement of micrometers or less for typical sounds, at kilohertz frequencies, corresponding to a speed of millimeters per second at most. It can be much less for faint sounds. The ear is a remarkably sensitive detector!
The ear canal is smaller than the wavelengths of audible sound. Thus, as sound passes by in any direction, the ear mainly responds to the pressure oscillations without regard to the direction of the wave. When a pressure peak surrounds the ear, air is (slightly) pumped into the ear, due to the random motions that equilibrate pressure. When a trough surrounds the ear, air is (slightly) sucked out of the ear. This happens at the frequency of the sound (say a thousand times per second), vibrating the eardrum.
Zwol's answer correctly notes that this can be seen as an instance of diffraction. It is a limit in which the hole is so small that the pressure at any instant is nearly uniform over the hole, so diffraction through the hole is nearly independent of the incident angle.
$endgroup$
While the mean air motion of the wave is in one direction (assuming a plane wave), the air molecules actually move in all directions. They are in local thermal equilibrium (due to frequent randomizing collisions), which is what gives meaning to pressure as the basis for modeling acoustics. This random molecular motion in all directions is at speeds of order the speed of sound, hundreds of meters per second.
The mean motion (longitudinal) is an oscillating displacement of micrometers or less for typical sounds, at kilohertz frequencies, corresponding to a speed of millimeters per second at most. It can be much less for faint sounds. The ear is a remarkably sensitive detector!
The ear canal is smaller than the wavelengths of audible sound. Thus, as sound passes by in any direction, the ear mainly responds to the pressure oscillations without regard to the direction of the wave. When a pressure peak surrounds the ear, air is (slightly) pumped into the ear, due to the random motions that equilibrate pressure. When a trough surrounds the ear, air is (slightly) sucked out of the ear. This happens at the frequency of the sound (say a thousand times per second), vibrating the eardrum.
Zwol's answer correctly notes that this can be seen as an instance of diffraction. It is a limit in which the hole is so small that the pressure at any instant is nearly uniform over the hole, so diffraction through the hole is nearly independent of the incident angle.
answered 6 hours ago
nanomannanoman
1511
1511
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Sarvesh Thiruppathi is a new contributor. Be nice, and check out our Code of Conduct.
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2
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it is not that simple . see hyperphysics.phy-astr.gsu.edu/hbase/Sound/sprop.html and links
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– anna v
2 days ago
2
$begingroup$
This website has some nice animations to show the three dimensional nature of longitudinal sound waves.
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– Farcher
yesterday
2
$begingroup$
Here's another pretty good explanation with animations, courtesy of the University of Southampton.
$endgroup$
– Ilmari Karonen
yesterday
2
$begingroup$
Almost everybody commenting or answering has completely misinterpreted the question. There is no need to rehash the entirety of an introductory course of waves, in 10 little bits and pieces, when the actual question is much more specific.
$endgroup$
– knzhou
19 hours ago
1
$begingroup$
@IlmariKaronen OP replied in several comments below, annoyed that answerers had misinterpreted his question. I just tried to condense them in a more digestable form.
$endgroup$
– knzhou
11 hours ago