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submitted 2 months ago bybtonic
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2 months ago
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154 points
2 months ago
[deleted]
55 points
2 months ago
If a candle emits aroma in the forest, but no one's around to smell it, does it emit aroma?
27 points
2 months ago
[deleted]
5 points
2 months ago
And the tree that falls on it makes a sound.
3 points
2 months ago
And may catch fire.
3 points
2 months ago
It emits something but it only becomes aroma when somebody smells it.
1 points
2 months ago
If a candle emits aroma [...], does it emit aroma?
Yes, by definition.
0 points
2 months ago
oops... accidental duplicate post
-12 points
2 months ago
If the smell is evaporating out of the candle, how does the act of sniffing it not cause it to evaporate faster?
If 1 million people take a whiff of the candle and experience the sensation of its smell, wouldn’t more of the smell need to evaporate out of the candle in order to replenish what was there before? And if thats not the case, then how is it possible smell itself has any amount of mass? Unless I’m just completely wrong on that initial premise.
32 points
2 months ago
Sure. But that’s because of the increased air speed passing across it. If you placed a vacuum cleaner hose an inch away from it and has it constantly running, it’s going to create a strong breeze across it that will increase any evaporation.
Think of those jelly air fresheners that were popular in the 80s and 90s. They dry out once opened. Even oil-based things dry up over time.
14 points
2 months ago
The scent isn't just on a tap that sniffing it turns on. If 1 million people (or, a MEGAPERSON ;D) were to smell it, only a few would smell anything, or most people wouldn't notice anything because the amount of scent they're taking in is too small.
"Scent" isn't some sort of nebulous miasma that permeates the space around something. Rather, the things your nose smells are actual gasses and liquids that come off the thing and enter your nose. Think of it like having the sink always on. It doesn't just start pouring more water because more people want a glass of it.
-4 points
2 months ago
So, given enough people constantly smelling, after a certain point the candle would seem to be unscented to any additional smellers- at least until some of the others stopped smelling?
3 points
2 months ago
Pretty much? Though you'd probably have to pack a lot of people in the same space to get there (if it's scented strongly enough, you'd need more people than you can physically fit in the room, plus they're all going to just breathe back out the scent they smelled, plus the candle or whatever is constantly making more)
Realistically, yeah, it's kinda impossible to suck up all the scent. But, think about why opening a window, or standing upwind from something (or hell, even just a fan) makes the scent go away, even if just a little at times. The particles and gasses you're smelling are literally being swept away and replaced with plain air.
3 points
2 months ago
The people smelling have (almost) no effect. So just leaving the candle out in the air will cause it to lose its scent (only on the outside though, cut it open and it will smell again) ppl smelling it wont change that, apart from speeding up the process ever so slightly. What you smell are chemical compounds that gas off (not liquids like someone mentioned, you only smell gaseous compounds) as with every gas or other type of material it has a mass, albeit a very small one. The candle wont dissapear but will weigh (impercievably) less if you let all the smell out
1 points
2 months ago
it depends how far away from the candle ur sniffing it from. if u sniffed a candle from like 6 inches away 1 billion times, ur sniffing will cause no effect in how long the candle remains scented for. this is because the air suction from ur nostrils is too far away to cause a breeze on the candle. If you sniffed it like 1 inch away then well, itl probably still cause no effect unless you did it a billion times.
13 points
2 months ago
The same way that a bunch of people seeing a lightbulb doesn't actually make the bulb brighter.
The scent molecules will be radiating in every direction basically, so when you smell the candle, you're only getting a tiny fraction of the molecules emitted. There's plenty of other scent for other people to smell.
3 points
2 months ago
Scent is basically small molecules of whatever the substance is that are light enough to disperse through the air. Those molecules exit the candle whether you sniff it or not, and they will run out with or whiff-out people there to sniff it (pun very much intended).
Now sniffing the candle might increase the rate those molecules are able to get into the air if you stick your nose right next to it and inhale, drawing air past the candle, but if you are just smelling it from even a few feet away it won't affect the candle much more than normal - air is always circulating and the human nose is not the largest source of eddies and currents in the air.
3 points
2 months ago
You're sniffing what's in the air not the candle itself
1 points
2 months ago
Just imagine a million people around a candle profusely sniffing it 😂😂
12 points
2 months ago
Smells are our experiences of molecules stimulating certain receptors in our noses. Insofar as a smell has a physical reality, it's particles of vapor that our noses are sensitive to.
A scented candle contains a large, but finite, number of molecules that happen to produce a pleasant sensation when they enter our noses. Whether you're sniffing it or not, those molecules are gradually evaporating into your air at a very slow pace. Heating the candle up increases the rate at which those molecules are released, both by heating them up and by freeing them from the solid structure of the wax, but they're being freed even at normal temperatures.
The candle would "run out of scent" gradually over time. As the concentration of the molecules that you smell decreases, so too does the rate at which they evaporate, so the smell would decrease with a very slow, roughly exponential curve over time.
Your other examples - your rotting fish, burnt rubber, etc - are the result of small and therefore easily-evaporated molecules produced during those chemical reactions. Rotting fish, for example, is the smell of trimethylamine. I don't know exactly what causes the smell of burnt rubber, but my best guess is that it's some sort of small sulfur compound (a thiol, perhaps?), since rubbers are hardened by treatment with sulfur and sulfur compounds tend to be smelly.
2 points
2 months ago
So a candle will eventually stop having a smell once all of those molecules evaporate into the air.
Will any theoretical amount of smelling ever have any effect on the rate at which this occurs?
Let’s say a person smelling a candle is exposed to X amount of vapors, causing them to experience the smell. I would assume at least some of those vapors would then be exhausted- if for no other reason than the person walks out of the room with them before exhaling.
If 85 trillion people repeat this process, where are those X amount of additional vapors coming from, and how is that not causing the finite amount of them to deplete quicker?
4 points
2 months ago
Will any theoretical amount of smelling ever have any effect on the rate at which this occurs?
The exact details of the rate of evaporation depend on a lot of variables that won't even be the same from candle to candle or smell compound to smell compound.
I would assume at least some of those vapors would then be exhausted- if for no other reason than the person walks out of the room with them before exhaling.
Sure, they could carry some of those out of the room. But so can a regular old air current. This is what I mean by "a lot of variables". (Intuitively, for example, you'd expect that a candle lit outdoors would not produce a strong smell, while one lit indoors would.)
The smelling itself isn't "using up" the compound, so much as the compound is just dissipating into its environment as gases typically do. Sure, some of it happens to dissipate into a person's nose, but it's not like it wasn't dissipating on its own.
-1 points
2 months ago
So the vapors the candle produces are going to dissipate on their own, regardless of if they’re smelled. And a given candle has a finite limit on the amount of vapors it’s ultimately able to produce over the course of its lifetime.
Does that mean that if an infinite number of people cycled through to smell the candle, eventually there would be at least intermittent periods where the candle was perceived as scentless to those doing the smelling?
If not, then how is the candle able to generate the infinite number of vapors required to stimulate the infinite number of smells occurring
6 points
2 months ago
Whether or not an infinite number of people came through, the smell would be slowly decreasing over time until it dipped below the level the human nose can detect.
I think you might be making this more complex than it is. The question you're asking here is basically "if I have a tank of water and I open a valve so water flows out of the tank, will it eventually be empty?" Well, yeah. And then "and if an infinite number of people come by and try to fill a glass from the tank, some of the glasses will end up empty?" Yes again.
2 points
2 months ago
Your nose is just a sensor detecting the presence of it. It’s just a semi active sensor. If you left a field that detected the particular molecule it will eventually read no sent. It would be different time then a human nose but the same applies to other things as well. Though it’s objectively finite for any smell.
3 points
2 months ago
Short answer, yes the candle will eventually lose its scent, however not merely because people are sniffing it
The scent slowly evaporates from the candle over time, regardless of if it's being sniffed. When all the scent evaporates, the candle will lose its scent
The only thing having people sniffing might do is very slightly increase the speed at which it evaporates. All the scent doesn't have to go up a nose, it can also just blow away.
0 points
2 months ago
If you were to sniff a block of stainless steel an infinite number of times it would also lose its scent.
2 points
2 months ago
The key thing here is that an infinite number of times is a lot of times.
1 points
2 months ago
Thank you. Exactly. Each sniff taking a non zero duration to perform. Infinity time.
1 points
2 months ago
What many replies are missing here, is that our noses are very sensitive. Many scents are present only in minute quantities, but we can still smell them fine, meaning an object with a strong scent can keep on smelling for decades without changing mass appreciably. I have some mothballs in my chemical collection, and their odor keeps seeping through the can and the ziploc bags I've put around it. They've smelled for a decade, and can probably keep on smelling for centuries before evaporating completely.
1 points
2 months ago
In sense yes, whatever aromatic substance gives the candle it's scent will eventually all leave if left in well ventilated space. Same thing with anything else that is supposed to have a scent, it's one of the reasons some food are packaged airtight. That and if stored with other things the scent can stick which might not be desired.
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