So what does happen to the sound? I can envisage some sort of timpani mode of induced oscillation occurring in a bowl of water at certain frequencies:
IIRC, when solving these sort of problems you have to consider the edge boundary condition too:
In general, there are two major types of boundary conditions: fixed-endpoint or Dirichlet boundary conditions, and free-endpoint or Neumann boundary conditions, corresponding to holding the end of a string or allowing it to freely oscillate, respectively.
I have pondered this because loudspeaker membranes work like this too, A corrugated edge speaker is more Dirichlet, a soft rubber surround speaker is more Neumann.
This is also used in string theory for fixed and unbound strings.
Water is an incompressible fluid. So, it’s unlikeOy that water in the bowls will act like membranes, especially considering the lack of acoustic energy where the bowls are sitting - the surface of the water is orthogonal to the direction of acoustic waves. So, I would be inclined to wave goodbye to that theory. 👋
Besides the membrane theory doesn’t account for the cold temperature of the water in the bowls, a critical feature of this experiment, cold temperature would make the water even more incompressible. Of course, one test the theory by observing if any ripples appear on the surface of the water, a possible sign of “membrane” action, which they won’t.
Besides the membrane theory doesn’t account for the cold temperature of the water in the bowls, a critical feature of this experiment, cold temperature would make the water even more incompressible. Of course, one test the theory by observing if any ripples appear on the surface of the water, a possible sign of “membrane” action, which they won’t.
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Here‘s another water experiment for y’all. Writing specific messages near water as it freezes into crystals. Not for the squeamish.
I could argue that I was referring to an 'anybody' you rather than a 'you' you.
But no, I should have written, "Just think of the money that could be made selling ice machines to misguided audiophools!".
I found an interesting fact about the incompressibility of water:
A mile deep in the ocean, the pressure is about 150 times normal atmospheric pressure.
Even when subject to that extreme pressure, water only compresses by less than one percent.
Those three (it must be precisely three of course!) bowls of ice water will lower the air temperature.
The sound will take longer to reach the listener because its speed decreases with air temperature.
The musical frequencies will, however, remain unchanged.
P.S. You will notice that Geoff did not claim the sound would change, he merely asked you to "listen to the sound".
So, nothing to see here. As Elsa sang in Frozen, Let it Go!
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When I said listen to the sound the implication is that the sound will be different, but also that the sound will be better. Why else would I post such a thing? Hel-loo!
Geoff Kait
Machina Dynamica
We do Artificial Atoms Right
Geoff Kait
Machina Dynamica
We do Artificial Atoms Right
You’re right, I’m promoting my knowledge. Like you, right? Like all of us. I’m a bit of a show off, I’ll grant you that.
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I said self-promotion: "The action of promoting or publicising oneself or one's activities".
I always like to remind myself what we are talking about with these Physics discussions:
Thus today I listened to Fields Medal winner Edward Witten discussing his illustrious applied mathematics career with Jim Al-Khalili:
https://www.bbc.co.uk/sounds/play/m001rycq
You only have to create an account with an email and a password to listen to this stuff on the BBC, though I don't know how available it is internationally..
Deeply interesting, and I remember how excited we all were in the Physics department when the J/Psi Charmed meson was discovered in October 1974.
String theory naturally creates the graviton, though it started as a theory of hadron Physics. Witten is famous for his unifying M-Theory amongst other things.
Witten reckons we might get a grip on it all in about a 100 years!
Also interesting was Paul Murdin, who was stricken with Polio as a child, talking about his work on discovering the first Black Hole detected, Cygnus X-1:
https://www.bbc.co.uk/programmes/m001qdln
https://en.wikipedia.org/wiki/Cygnus_X-1
He was a pal of Patrick Moore it seems! Small World.
Thus today I listened to Fields Medal winner Edward Witten discussing his illustrious applied mathematics career with Jim Al-Khalili:
https://www.bbc.co.uk/sounds/play/m001rycq
You only have to create an account with an email and a password to listen to this stuff on the BBC, though I don't know how available it is internationally..
Deeply interesting, and I remember how excited we all were in the Physics department when the J/Psi Charmed meson was discovered in October 1974.
String theory naturally creates the graviton, though it started as a theory of hadron Physics. Witten is famous for his unifying M-Theory amongst other things.
Witten reckons we might get a grip on it all in about a 100 years!
Also interesting was Paul Murdin, who was stricken with Polio as a child, talking about his work on discovering the first Black Hole detected, Cygnus X-1:
https://www.bbc.co.uk/programmes/m001qdln
https://en.wikipedia.org/wiki/Cygnus_X-1
He was a pal of Patrick Moore it seems! Small World.
Gulu, you say potato, I say patahto. 😐 I do not discuss my products on audio forums, unless of course it comes up, which sometimes happens, but not that much. I also do not sell to anyone on audio forums.if I did, that would be a conflict of interest. I don’t like conflicts.
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