Make up your mind Google AI. Is sound faster in air that is less dense or more dense?
Honestly, there is so much wrong in the AI answers that it’s hard to know where to start, but the direct contradiction of itself seems like a good start.
This seems like a difficult thing to get right. To me it would intuitively seem like air transmits sound easier than e.g. water or steel since there is less to dampen the waves. But that’s just wrong. You shouldn’t trust intuition when it comes to physics, even if you are a physicist.
I’m not a physicist and I’m taking a stab without looking it up.
Is there an index of refraction or something so that if you transmit through air than water than air you would think that sound is “dampened”?
I’m having a hard time with just an object though. Is the speed of sound a constant? I’ve never heard it defined with respect to to air
I am a physicist, for context. Please just use a table for the values in air.
What do you mean with index of refraction? For light this refers to the speed of light in the medium. In this sense you can define a index of refraction for sound, but would you want to? It has very little to do with dampening (dampening is usually wave length depended so they are usually proportional).
The speed of sound in air is ca. 300m/s, in water 1500m/s. so their relative index of refraction are 5. This implies rather difficult transition of sounds between medias since most sounds are going to be reflected. Refer to frustrated reflection.
The physics of why denser air is claimed to have a slower speed of sound is not clear to me, but I suspect there is some bullshit going on since the question is not sensical. You can’t double the density of a gas without changing other parameters like Temperature or Pressure. Refer to the ideal gas law.
There’s an easy formula for ideal gases: c = sqrt( gamma * R * T ) = sqrt( gamma * P / rho ). [Express ideal gas law as P = rho * R * T using a gas constant tailored to your species].
So in isobaric (equal pressure) conditions, there is an inverse relationship between speed of sound and density.
But the atmosphere is not isobaric, especially not on its vertical axis. For the first layer of atmosphere, the vertical profile can be roughly characterized by a linear drop in temperature from sea level to 11 km altitude. In this region the speed of sound is therefore also dropping linearly, but the air is also getting less dense.
Source: programmed air data software for aircraft.
Please note that R is an arbitrary constant and so is gamma. Thanks for providing the formula, but I still fail to remember the reasoning for it. But such is life
I haven’t looked into how it is derived, but if it helps, I R and gamma aren’t constants that are exclusively used for this equation (if that’s what you mean by arbitrary).
R is the ideal gas constant, which is no more arbitrary than any other physical constant like the speed of light in a vacuum or the elementary charge.
Gamma is the heat capacity ratio of the gas, which is the ratio of the gas’s heat capacity at constant pressure to that at constant volume. It’s a property of the material like density or viscosity and is used in many calculations involving gases.
In my opinion the gas constant is rather arbitrary but only in the same vein as e is, ie. It can be transformed away by choosing weird units.
Thanks for clearing up what you meant with gamma.
R is the Boltzmann constant multiplied by Avogadro’s number. It’s not more arbitrary than any other physical constant.
Yes.
Hm, okay. So sound /does/ travel at different speeds in different mediums. Haven’t heard that before.
I guess the refraction (defined the way you assumed) has applications with noise reduction in, say, a building.
As sound appears to travel faster through liquids than gas, I would imagine the answer is the particles don’t have to travel as far to transmit energy if the particles are closer?
Sound is usually mitigated not by choosing materials that absorb it when it travels through them, but by isolating parts of the building.
Also Eg. Resonances are a problem. Placing furniture and geometric shapes in rooms is so much easier than say putting it underwater ;) much more practical, too.
Sound usually carries quite far so increasing the speed of sound doesn’t do a whole lot. Might work decent for high frequency noise but that’s not really a thing that is done.
The other commenter provided the formula for the speed of sound in an ideal gas. Please refer to that.
Sounds like maybe you want acoustic impedance ? Just like optical index mismatch, or electrical impedance mismatch, you get reflections at discontinuities. Neat stuff!
Not exactly sure what you mean by air-water-air “dampening,” but my suspicion is that you’re referring to sound being reflected at each interface, so the transmission is reduced. Antireflective coating, index matching, impedance matching are all rich topics in physics and electronics!
Yes the transmission reduction you need mentioned. Thank you
Its all just garbage that gets in the way. My W11 systems was randomly bogging down during documents, excel and powepoint. it was the AI service hogging resources, (c packaged with Office.) Easy fix, just delete the AI executables in a folder, but a product update will probably bring the back.
And the product updates will happen without you asking them to! And if you disable them, seemingly unrelated windows updates will helpfully fix your mistake.
I have found similar contradictions for biology searches. AI in many ways is just a glorified search engine, and it makes mistakes based on what’s available to it.
At least a traditional search engine doesn’t torch an couple acres of rainforest just to give you wrong information.
I don’t understand why people are complaining about these shitty features instead of just turning them off.
Because it can have negative impacts on the lives of people who aren’t savvy enough to double check the info. There’s already enough misinfo on the internet. We don’t need a (formerly) trusted source spreading more.
Not everyone is savvy enough to turn it off, for one. The average person isn’t even going to think about turning it off. That means a lot of people are now being fed a top search result that is the wrong info half of the time. Not just the wrong webpage, but actually the wrong information.
For another thing, it shouldn’t be on by default if it’s so bad. If this was a traditional bug giving you incorrect search results half the time, it wouldn’t be released. But because of this AI race that’s happening, google is willing to release this massive bug live, and on by default. We should be complaining about it!
I also think part of the problem is that it seems really useful. At first glance it seems like it has quickly and succinctly summarized the information that is deep inside other web pages, and presented the answer to specifically what i was looking for (quite confidently, at that.) It’s very easy to fall into a trap of trusting the information told to you.
Yeah I was addressing the audience here on Lemmy though. I get thinking the feature sucks but you can turn it off, which I did a while ago. I think it would make a lot more sense to complain about this in a setting like reddit where you’re not preaching to the choir so directly.
On Lemmy, I feel like 90% of users can build an app from source and debug dependency issues to make it happen. So it’s just odd to me that I still see this getting beat to death here.
Just because you can turn it off for yourself doesn’t mean the problem no longer exists.
No one said it no longer exists. Just that if you know you can turn it off but refuse to, you kind of have no right to complain about it.
Yes, you do. You can complain about google (or whoever) feeding disinformation to the masses.
That’s not what you’re doing. You’re complaining about something you could easily fix for yourself. Have fun with that.
I wasn’t complaining. I was making fun of it, pointing out how dumb it is. I thought people would appreciate it (and it seems to be the case, with a few exceptions) and I created the community so there was a contained place for people to do the same. You don’t have to participate in it, there’s a way to turn off that feature.
However, I responded to your comment about people complaining because I think people have every right to complain. You seem very focused on the problem being for individuals, when I think the problem (that I’m talking about) is much bigger than that.
And no, I can not fix Google giving incorrect information to billions of people.
“I neeeeed them for wooorrrrrrrk”
I dunno. The hypetrain might be the biggest we’ve seen in our lifetimes, relative to the actual impact of the, y’know, thing. That’s Trillions of Quattloos worth of hype out there pumping the lies of what it can do to people who can’t remember how to clear the cache.
please show me the off button
In a browser, this will help: https://tenbluelinks.org/
If in the mobile app, look in settings and there are settings related to AI and “labs” that you can turn off.
In water at least both higher temperature and higher pressure will result in higher sound velocity. Weird that it is different for air. I would have assumed that they behave the same.
I guess that the fact that water is incompressible must have something to do with it.
Water is weird because it expands as it gets colder.
Only if it freezes
Also in 4 -> 0 °c range
AI is like an accountant who answers “What do you want it to be?” when you ask what 2 + 2 is.
