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Jeanway

Speed Of Smell

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How fast does odor travel? Or does it? In still air it travels, across a room. Or does it just use air currents? The molecules travel. While cooking something, like broccoli or cabbage, stinks up the whole house. A skunk's odor can ruin a whole neighborhood for a while. :rofl: Why is it so hard to get that smell off you? Anyone ever studied this? Aromatherapy? Smells can trigger memories, long forgotten. My mother's perfume can trigger so many :( . Salt air, Honey suckle, bread baking. Did you know our sense of smell is 10,000 times greater than our sense of taste? :rofl:

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This is a fascinating question because it relates to thermodynamics and statistical mechanics. As you said, odor is produced by molecules of.... something in the air. At room temperature, if a molecule is in thermal equilibrium with its environment, it may travel roughly 500-1000m/s - based on a quickie calculation I just did. (Couple times the speed of sound - ballistic!) However, in the process of moving, it will collide with other molecules and bounce around, so it's effective (diffusion) speed is determined by its thermal velocity and it's "mean free path." Think of a room filled with marbles, and you have another marble moving through this room. To get to the other side of the room, the marble's speed to get there depends on its own speed and also on how many marbles are in the room because it will bounce around in getting there. More marbles (particles) means a shorter "mean free path" and so a smaller diffusion speed. This is also affected by things like thermal gradients and convection.

 

I heard somewhere that smell is the sense most closely related to memory. That makes sense to me becuase I'm always forgetting people's names, but I never forget the smell of popcorn.

 

Pretty fascinating stuff.

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A couple times the speed of sound? That's amazing nik. I didn't think it was that fast. I mean a gas leak takes time for people to notice. It's thermal velocity and 'mean free path' meaning how hot the air is and how many ' other' molecules are in the air. And why are some odors so 'PUNGENT'?

 

Now nik, also why is it we experience ' nasal fatigue '? Why can't we 'refresh' somehow? I mean the tongue can be cleansed or refreshed why not the nose? Or is this more of an anatomical question than one of chemistry? I believe the maximum number of allowable, discernable scents is 3.

 

 

One last question. What is the deal with 'beans' anyway? :rofl: Why nik, why? :rofl:

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A couple times the speed of sound? That's amazing nik. I didn't think it was that fast.  I mean a gas leak takes time for people to notice.  It's thermal velocity and  'mean free path' meaning how hot the air is and how many ' other' molecules are in the air. And why are some odors so 'PUNGENT'?

 

Now nik, also why is it we experience ' nasal fatigue '? Why can't we 'refresh' somehow? I mean the tongue can be cleansed or refreshed why not the nose? Or is this more of an anatomical question than one of chemistry? I believe the maximum number of allowable, discernable scents is 3.

 

 

  One last question.  What is the deal with 'beans' anyway?  :( Why nik, why? :rofl:

the nose has a few hundred thousand or was it million it can discern. It depends on the personand the sensitivity of the recepticles of the particles entering the nose. FYI: Particles of the material you are smelling enter the nose...

So when you go to the bathroom, remember that you're actually putting poop up your nose!!!! :) :rofl: :( :)

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A couple times the speed of sound? That's amazing nik. I didn't think it was that fast.  I mean a gas leak takes time for people to notice.  It's thermal velocity and  'mean free path' meaning how hot the air is and how many ' other' molecules are in the air. And why are some odors so 'PUNGENT'?

 

Now nik, also why is it we experience ' nasal fatigue '? Why can't we 'refresh' somehow? I mean the tongue can be cleansed or refreshed why not the nose? Or is this more of an anatomical question than one of chemistry? I believe the maximum number of allowable, discernable scents is 3.

 

 

  One last question.  What is the deal with 'beans' anyway?  :) Why nik, why? :rofl:

the nose has a few hundred thousand or was it million it can discern. It depends on the personand the sensitivity of the recepticles of the particles entering the nose. FYI: Particles of the material you are smelling enter the nose...

So when you go to the bathroom, remember that you're actually putting poop up your nose!!!! :( :rofl: :( :)

This topic reminds me that when I go into someone's house and it smells like air freshener they're really just trying to cover up something smellier. :)

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Oh yes, the kinetic energy of individual particles in a gas at room temperature is surprising, but keep in mind the gas has other molecules as well. Imagine trying to spint in a crowded room at a party (Try it. It's fun.)

 

I don't know too much about how the nose works, but I could probably make an educated guess (OK, semi-educated). Since the sensors in the nose transmit electro-chemical signals to the brain, we consciously sense them (the frontal cortex), many time experience a response (the hypothalamus amygdala), and remember them (the hippocampus), I imagine that that the center of the brain responsible for smell develops an adaptation mechanism to decrease the response to the chemical response of the sensory neurons in the nose. This response is probably similar to the adaptation to the sense of touch. Do you know what it's like to get a new watch, new shoes, glasses, or contact lenses. You are always aware of them when wearing them, but after a while adapt to them. Could you imagine what it would be like to constantly be aware of our clothes all the time as we are wearing them. We'd go nuts! The brain must develop a similar response to smell. As I said, I'm not too knowledgeable about this. I bet Unadopted Angelic or The Unicorn Hunter know about this, as they've studied this sort of thing.

 

I did not know this fact about being able to discern a maximum of three simultaneous scents. Interesting! Very interesting!

 

Do you know anyone without a sense of smell or a very poor sense of smell? I know a few. Fascinating people!

 

Beans? I'm sorry, I'm at a loss as to what you're talking about. I must really be out in left field on this..... Do mean like "running on someone's bean?" Is this a subtle hint?

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:rofl: No nik, Not " Tu marche sur mon haricot "? :( :rofl: You are so funny. Beans, you know like Pork and Beans, baked beans ? And what does 'spint' mean? Spint across a room? Do you mean 'sprint'? Or 'spit'? :(

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Uh.... yes. "Sprint" Sorry. I recommend that one SPRINTs accross a crowded room. However, the application could also apply to spitting across a crowded room. Yeah sure. Give that a try too!

 

Oh, I get it! Why are beans associated with bad smells! AHA! Beans are loaded with protiens AND the digestive process involved produces a lot of methane and some other stuff (I can't remember the reaction at the moment, dang!). It's like a fermenting process (ever had natto?). On the same subject, I used to hang out with a lot of weight lifters, and they would drink high protien drinks (more than 20 grams a shot). This would have the same effect as beans. Even worse, some of the drinks had egg protein in it, and the process to produce this resulted in a little extra sulfur in the powder, so the... ahem.... results would smell like sulfur too. They couldn't just eat a lot of chicken. We kept the windows open a lot.....

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:assimilated::klingon: So what's the deal with 'BEANO' then? Proteins, I thought it was that we couldn't digest the bean 'skin' and that's what was doing all the damage :wub: :)

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:assimilated:  :klingon:  So what's the deal with 'BEANO' then? Proteins, I thought it was that we couldn't digest the bean 'skin' and that's what was doing all the damage :wub:  :)

Beano! Beano? ....... Beanooooooooo......... hmmmmm?

 

Touche, encore, Jeanway! Qu'est que c'est le Beano? C'est un jouet pour les enfants?

 

I'm sorry, Jeanway. You've stumped me again. What's beano? Is that anything like the card game bunco? (This may be one of those cultural differences I spoke of.)

 

Happy to admit what I don't know, Jeanway! "The fool doth think he is wise, but the wise man knows himself to be a fool."

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BEANO is a product you can buy. It's a small bottle of liquid which you take a few drops of before you eat something that causes, well, um, excessive flatulence :klingon::assimilated:

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I see. You would think I've seen that before. Does it contain charcoal? I used to feed charcoal to my birds for things like upset stomachs, etc.

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You know it just occured to me that there was a team of researchers working on Beano for years before it was perfected. Didn't anybody tell these guys someone could just strike a match or in the least hold their nose until the wind shifts. :assimilated:

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I see.  You would think I've seen that before.  Does it contain charcoal?  I used to feed charcoal to my birds for things like upset stomachs, etc.

 

 

 

 

 

 

 

 

 

Your asking Me? :assimilated: I'm asking you. :klingon:

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hmmmm..... As you can clearly tell, I'm out of my league here. Perhaps we should consult the Jedi Holocron.

 

 

By the way, Fenriz, your remark reminds me that many inventions had very strange beginnings - Gatorade for example.

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The speed of smell is limited to the sensitivity of you nose (the number of receptors and range of smell identified) and the speed of you nervous/respritory system.

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The speed of smell is limited to the sensitivity of you nose (the number of receptors and range of smell identified) and the speed of you nervous/respritory system.

This reminds me of something I did a few years ago in college. A couple of friends and I did an experiment to measure neuron transmission speed. We connected mechanical stimulators to various body parts (hand, foot, neck, back, etc.) which remotely pricked the subject, after which the subject responded by pushing a button as soon as the pain was felt. By estimating the distance from the brain of the various receptor points, we were able to get a pretty good linear fit of the reaction time to distance from the brain, and thus subtract the offset of the response time. We all took turns to get averages. I can't remember what the transit speed was, but I think it exceeded the speed of sound in air. I'll have to see if I still have my notes on that. Of course, that's independent of the transmission of particles through air. It was a neat little test, however.

 

This wasn't a class project, it was just for fun.

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The speed of smell is limited to the sensitivity of you nose (the number of receptors and range of smell identified) and the speed of you nervous/respritory system.

This reminds me of something I did a few years ago in college. A couple of friends and I did an experiment to measure neuron transmission speed. We connected mechanical stimulators to various body parts (hand, foot, neck, back, etc.) which remotely pricked the subject, after which the subject responded by pushing a button as soon as the pain was felt. By estimating the distance from the brain of the various receptor points, we were able to get a pretty good linear fit of the reaction time to distance from the brain, and thus subtract the offset of the response time. We all took turns to get averages. I can't remember what the transit speed was, but I think it exceeded the speed of sound in air. I'll have to see if I still have my notes on that. Of course, that's independent of the transmission of particles through air. It was a neat little test, however.

 

This wasn't a class project, it was just for fun.

I thought nerve transmission was around 200 kph not beyond speed of sound...

Or am I wrong???

I don't know...

I'm not sure...

Heck, I'm never sure...

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As I said, I don't remember...... If I can't find my notes, I'll have to do the test again.

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PPPSSSTTTT, nik, Hey nik, Come here...::whispers in nik's ear:: Let me tell you about WeareBorg. RUN! :) :blink:

And don't look back. :blink:

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SO WHAT YOUR SAYING IS THAT WHEN SOMEBODY FLATULATES IT'S COMING AT YOU AT TWICE THE SPEED OF LIGHT :blink: OMG! :blink:

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SO WHAT YOUR SAYING IS THAT WHEN SOMEBODY FLATULATES IT'S COMING AT YOU AT TWICE THE SPEED OF LIGHT :) OMG! :blink:

who said that??

That's not possibe..

and I don't get the thing with nik...

:blink:

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Don't be a BUZZKILL :blink:

Edited by Jeanway

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What's "the thing with nik?"

 

I think that of all the senses, smell is one that humans can adapt to losing most easily. I find it fascinating that people can lose a sense -any sense- and still adapt. Also, I find fascinating about a lack of olfactoray sensation is that it CAN be dangerous (think about things like gas leaks, etc.). The result is that the person either seems incredibly foolhardy or finds very subtle ways to rely on the senses of others. Consider a blind person. In many cases, they rely obviously on things like walking sticks, dogs, and other people to see. I have yet to see another person with a "smelling nose" dog or constantly asking a companion "What do you smell? What do you smell, now? How about now?" How is it done?

 

Actually, I know the answer to this. I also have no sense of smell (part of the reason I find these people fascinating). (Childhood illness did it in for me.) We just don't. Sure I wish I could smell things like popcorn, and have spent hours in a house leaking gas. However, as Jeanway, pointed out, smells can trigger lucid memories. There's something....... interesting about being detached from all that.....

 

WEAREBORG's not so bad..... persistent. That's good. I always tell aspiring scientists that what makes a good scientist is not knowledge, for that is imparted. It is patience. Learn to go for days, weeks, months, and years before getting an answer, and perhaps you will be a scientist.

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OH, nik, I'm so sorry. :drool:

Don't worry about it..... I know you were just teasing WEAREBORG. He's a good kid.... for a Borg.

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Something just occureed to me as I was reading this post. There are to things that were not mentioned, (now remember this is Macro, not Micro Dynamics)

 

and they are Gravity/ Magnetic field ( without which scents/ smells

would float off into space)

Atmosphere( without which air currents would not be produced)

 

Sorry I'm on my 3'rd cup of coffee right now

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Semper= Always

 

Gumby= Flexible

 

Semper Gumby= Always Flexible. :lol: Its the nature of my employment.......

:angry: :lol:

 

It can sometimes get in the way of well... "Life, Itself"

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