The Science Thread
November 4th, 2011 at 6:11:46 PM
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This was mentioned before, so I figured I'd give it a whirl and see if it takes off. Science and math is like peas and carrots, no?
I thought Wiz's Spanish WoD format was very clean, the way he posted a topic, allowed a few days of comments, then posted another. Maybe this one can be as organized. In any case, feel free to join in or pose questions of your own. I'm in no way claiming this thread since I'm not exactly an expert in these matters, I only wanted to get it started because I have a high interest. There's been a number of discoveries these past years and I only expect them to continue; now there's a place to discuss them.
I'll pose the first question to get things started. Just bear with my absurdity. You're not likely to hear something profound from me and my first topic is no exception, I just have a number of questions I feel would better my understanding of my world around me. If nothing else, I might get a giggle or two =)
Stand by for my first lighthearted, elementary question....
I thought Wiz's Spanish WoD format was very clean, the way he posted a topic, allowed a few days of comments, then posted another. Maybe this one can be as organized. In any case, feel free to join in or pose questions of your own. I'm in no way claiming this thread since I'm not exactly an expert in these matters, I only wanted to get it started because I have a high interest. There's been a number of discoveries these past years and I only expect them to continue; now there's a place to discuss them.
I'll pose the first question to get things started. Just bear with my absurdity. You're not likely to hear something profound from me and my first topic is no exception, I just have a number of questions I feel would better my understanding of my world around me. If nothing else, I might get a giggle or two =)
Stand by for my first lighthearted, elementary question....
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November 4th, 2011 at 6:28:31 PM
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TOPIC: Why Isn't 70*F Always 70*F?
This time of the year always begs this question from me. My house, depending on a few variables, is always maintained at a temp ranging from 70*F to 74*F. My basement is even more stable, ranging only from 68*F to 70*F. I have central heat and air, so no matter if it's -9*F or 95*F outside, the house stays in the above range.
So why does it FEEL so bloody different? In summer, I hop out of the shower, dripping wet, into my 72* house and it feels like heaven, absolute bliss. Yet in winter, even though my house is still 72*, I have on sweatpants, thermal shirts, wrapped in a blanket, and I'm STILL cold. The basement in summer is a blessed retreat, somewhere I wish I could stay for hours, yet in winter, it's an icy dungeon not fit for Russian criminals. What gives?
Stupid as it sounds, this is a dead serious question, one I've pondered for years yet can't solve. 72* should always be 72*, right?
The only possible answer I've ever had is the evaporation factor. Winter house heat is a dry heat, which allows faster evaporation of your body surface's moisture, which would cause the feeling of being colder. But I can't believe that such a slight change in evaporation could cause such an extreme difference - on one hand I can be stark naked, dripping wet and loving it, on the other hand I can have on 3 layers and still be cold.
Thoughts?
This time of the year always begs this question from me. My house, depending on a few variables, is always maintained at a temp ranging from 70*F to 74*F. My basement is even more stable, ranging only from 68*F to 70*F. I have central heat and air, so no matter if it's -9*F or 95*F outside, the house stays in the above range.
So why does it FEEL so bloody different? In summer, I hop out of the shower, dripping wet, into my 72* house and it feels like heaven, absolute bliss. Yet in winter, even though my house is still 72*, I have on sweatpants, thermal shirts, wrapped in a blanket, and I'm STILL cold. The basement in summer is a blessed retreat, somewhere I wish I could stay for hours, yet in winter, it's an icy dungeon not fit for Russian criminals. What gives?
Stupid as it sounds, this is a dead serious question, one I've pondered for years yet can't solve. 72* should always be 72*, right?
The only possible answer I've ever had is the evaporation factor. Winter house heat is a dry heat, which allows faster evaporation of your body surface's moisture, which would cause the feeling of being colder. But I can't believe that such a slight change in evaporation could cause such an extreme difference - on one hand I can be stark naked, dripping wet and loving it, on the other hand I can have on 3 layers and still be cold.
Thoughts?
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November 4th, 2011 at 7:09:04 PM
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Damn good question IMO. I think you might be right, it might have to do with humidity, is it ever bitter cold and humid? Always the chance too that you brain is tricking you because of you're aware that is much colder or hotter outside your home.
when man determined to destroy himself he picked the was of shall and finding only why smashed it into because."
— E.E. Cummings
November 4th, 2011 at 7:29:56 PM
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I don't know that evaporation rate is the key here, but the humidity is an important factor. First, to confirm a part of what you have already said:
In the winter, when it is cold outside, there is little water content in the outside air, even at rather high relative humidity levels (as heard on the TV weather report). The cold air just cannot maintain as much water vapor as the warm/hot summer air. Since your house is not air-tight, you have some of this dry, cold air finding its way indoors. Once your furnace heats it to 70F, its relative humidity is very low. You have already acknowledged that in your post, and this very low humidity is the key reason that static electricity tends to be more of a problem in the winter -- it is difficult to dissipate the charge without the moisture.
The energy content of the atmosphere in your house is a combination of the energy of the air (Nitrogen, Oxygen, Carbon dioxide, etc) and the energy content of the water vapor (humidity). Think of this water vapor as steam that has been added to the otherwise dry air. At the same temperature, a room atmosphere that has higher humidity has greater energy content than a room atmosphere with low humidity. Thus, you typically have more energy in the room (air energy plus water vapor energy) in the summer than in the winter, even if you maintain the same temperature.
You can adjust that by adding a humidifier and running it in the winter. It will cost you money to evaporate the water that is added to the room atmosphere, but then the air will feel warmer at the same temperature. I cannot recommend a residential humidifier without also offering a bit of a warning: most of them involve moistening some sort of porous material that your air is circulated through (which initially cools the air) relying on the furnace to maintain the desired temperature. Unfortunately, these damp, porous fabrics tend to be fertile breeding grounds for various biological growths (Legionaire's disease, anyone?). In commercial buildings, the winter humidity level is typically raised by direct injection of steam from the boiler into the duct work.
In the winter, when it is cold outside, there is little water content in the outside air, even at rather high relative humidity levels (as heard on the TV weather report). The cold air just cannot maintain as much water vapor as the warm/hot summer air. Since your house is not air-tight, you have some of this dry, cold air finding its way indoors. Once your furnace heats it to 70F, its relative humidity is very low. You have already acknowledged that in your post, and this very low humidity is the key reason that static electricity tends to be more of a problem in the winter -- it is difficult to dissipate the charge without the moisture.
The energy content of the atmosphere in your house is a combination of the energy of the air (Nitrogen, Oxygen, Carbon dioxide, etc) and the energy content of the water vapor (humidity). Think of this water vapor as steam that has been added to the otherwise dry air. At the same temperature, a room atmosphere that has higher humidity has greater energy content than a room atmosphere with low humidity. Thus, you typically have more energy in the room (air energy plus water vapor energy) in the summer than in the winter, even if you maintain the same temperature.
You can adjust that by adding a humidifier and running it in the winter. It will cost you money to evaporate the water that is added to the room atmosphere, but then the air will feel warmer at the same temperature. I cannot recommend a residential humidifier without also offering a bit of a warning: most of them involve moistening some sort of porous material that your air is circulated through (which initially cools the air) relying on the furnace to maintain the desired temperature. Unfortunately, these damp, porous fabrics tend to be fertile breeding grounds for various biological growths (Legionaire's disease, anyone?). In commercial buildings, the winter humidity level is typically raised by direct injection of steam from the boiler into the duct work.
November 4th, 2011 at 9:09:29 PM
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Humidity.
A wet cold can feel "bone chilling," and a dry cold much less intrusive.
A wet cold can feel "bone chilling," and a dry cold much less intrusive.
"What, me worry?"
November 4th, 2011 at 9:18:28 PM
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Quote: DocI don't know that evaporation rate is the key here, but the humidity is an important factor.
As a general rule high humidity makes it seem colder when the temperature is below 53 degrees F and warmer when the temperature is above 53 degrees F.
A heat index chart is only concerned about temperatures above 80 degrees F where high humidity makes it seem warmer.
November 4th, 2011 at 9:59:35 PM
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I think this particular question relates to the temperature, or temperature range, at which Face maintains his house or basement, nominally 70F, rather than the outdoor temperatures we are likely to encounter.Quote: pacomartinAs a general rule high humidity makes it seem colder when the temperature is below 53 degrees F and warmer when the temperature is above 53 degrees F.
A heat index chart is only concerned about temperatures above 80 degrees F where high humidity makes it seem warmer.
The HVAC folks often talk about comfort zones, which reflect a combination of temperature and humidity and indicate the conditions that are considered acceptable or comfortable to most people for their work environments. This may not be the best illustration, but it is one that I found conveniently posted on the web. You may see that for any particular room temperature (such as Face's 70F) as the humidity increases, people are less likely to consider the room too cold. Similarly, at 82F, increased humidity is more likely to have people feeling too hot.
The comfort vs. humidity relationship may be quite different if you are far outside of this range of typical indoor temperatures.
November 4th, 2011 at 11:36:11 PM
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Doc is exactly right. Moist air retains heat longer so if you have low humidity in your home your heating system will have to work harder (longer) to maintain the desired temperature. As far as his comment about humidifiers being a breeding ground for bacteria and the like, get a flow-through humidifier and you won't have standing water, eliminating (almost completely) this issue.Quote: DocUnfortunately, these damp, porous fabrics tend to be fertile breeding grounds for various biological growths (Legionaire's disease, anyone?).
Happiness is underrated
November 5th, 2011 at 12:06:27 AM
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Thanks all for playing along, especially Doc, who's seemingly willing to forsake his nap to rescue me from my own absurdity. ;)
I must admit I'm embarrassed, almost to the point of shame, that I came far enough in thought to realize humidity was the cause, but not far enough to realize why. I reckon this also explains why 110* air from a blowdryer feels kind of nice, while 110* water from a hot cocoa burns like hell. Same concept, correct? The air has the same temp, but "not as much", as it were, so it disperses rapidly, while the cocoa has the energy and can kind of keep it there longer. To make an analogy, you could cup your hand and open a lighter into it, filling it with gaseous butane and lighting it in a fireball, and not get burned. But if you just light a lighter in your hand, you go to the hospital. They're both the same temp, but the fireball (air) releases all it's energy quick, whereas the lighter (water) keeps that energy on you longer.
God, so simple ><
I'm cooking up another temperature question that actually has real world application. I'll let this simmer for now and probably post it tomorrow. It starts strange (like all my stuff) but there is a point to it. Promise ;)
I must admit I'm embarrassed, almost to the point of shame, that I came far enough in thought to realize humidity was the cause, but not far enough to realize why. I reckon this also explains why 110* air from a blowdryer feels kind of nice, while 110* water from a hot cocoa burns like hell. Same concept, correct? The air has the same temp, but "not as much", as it were, so it disperses rapidly, while the cocoa has the energy and can kind of keep it there longer. To make an analogy, you could cup your hand and open a lighter into it, filling it with gaseous butane and lighting it in a fireball, and not get burned. But if you just light a lighter in your hand, you go to the hospital. They're both the same temp, but the fireball (air) releases all it's energy quick, whereas the lighter (water) keeps that energy on you longer.
God, so simple ><
I'm cooking up another temperature question that actually has real world application. I'll let this simmer for now and probably post it tomorrow. It starts strange (like all my stuff) but there is a point to it. Promise ;)
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November 5th, 2011 at 12:44:58 AM
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I think there is a third factor, seldom mentioned: ambient radiant infared heat. This is one reason systems with heat pumps tend to disappoint.
the next time Dame Fortune toys with your heart, your soul and your wallet, raise your glass and praise her thus: “Thanks for nothing, you cold-hearted, evil, damnable, nefarious, low-life, malicious monster from Hell!” She is, after all, stone deaf. ... Arnold Snyder
November 5th, 2011 at 6:16:50 AM
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Quote: FaceI reckon this also explains why 110* air from a blowdryer feels kind of nice, while 110* water from a hot cocoa burns like hell. Same concept, correct?
No. That's basic thermodynamics. Temperature does not equal heat. It takes more heat to warm water than it takes to warm air. So a volume of air at X degrees contains far less heat than the same volume of water at the same temp.
Also water conducts heat much better than air. So hot air transfers less heat than water.
I don't recall the definitions, but they involve the total volume of an object and the kinetic energy of its atoms and/or molecules in the case of heat.
As for the gas trick, it's about density. The gas from the lighter is less dense than air, more so when it's lit. When you open your palm and light the gas, it's already moving away from your palm. If you apply the flame to the hand, though, all the heat energy goes to your palm.
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November 5th, 2011 at 9:13:15 AM
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Quote: FaceI reckon this also explains why 110* air from a blowdryer feels kind of nice, while 110* water from a hot cocoa burns like hell. Same concept, correct?
(I tried to post a reply, but somewhere in the process, everything I typed disappears. If it shows up somewhere later, please excuse my clumsiness. I'll try again here.)
Face, you have stepped over into another area of thermal sciences here: convection heat transfer. Convection (as opposed to conduction or radiation heat transfer) is when there is a fluid (liquid or gas) and a solid surface at a different temperature. The fluid either heats or cools the surface. The term "convection" is also used to describe the related-but-different phenomenon of energy being carried along with a moving fluid.
A slightly-irrelevant (for now) issue that might arise if this discussion is carried further is that there are three categories of convection heat transfer: (1) natural convection, in which the heat transfer changes the temperature and density of the fluid causing it to rise/fall which assists in carrying energy toward or away from the solid surface (i.e., natural currents), (2) forced convection, in which the fluid is moved past the solid surface by a fan, a pump, or motion of the solid surface, and (3) phase-change heat transfer, in which the fluid is boiling or condensing at the solid surface, as in a pan of water on the stove. Generally, the rates of heat transfer (for a given difference in temperature) is lowest in cases of natural convection, higher with forced convection, and highest of all when there is phase change occurring. This rate of heat transfer for a given temperature difference is characterized by a "convection heat transfer coefficient."
In general, liquids offer higher convection heat transfer coefficients than do gases, in both natural and forced convection. That is the reason the 110F or even 140F air blowing on your skin feels warm, while water at a similar temperature and similar flow feels scalding -- the water transfers heat to your skin much more effectively than the air does, causing sensations of both higher temperature and greater pain.
Edit: It works the other way, too. Exposing your skin to 35F air blowing across it on a chilly autumn morning feels "brisk", while dipping your hand in a flowing 35F stream of water feels frigid. Water provides greater rates of convection heat transfer than air (for the same temperature difference) in either direction.
November 5th, 2011 at 1:51:34 PM
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Quote: NareedNo. That's basic thermodynamics. Temperature does not equal heat. It takes more heat to warm water than it takes to warm air. So a volume of air at X degrees contains far less heat than the same volume of water at the same temp.
But isn't that kind of what I was saying? (Asking you what I was saying, sheesh ;)) Summer 70* is warmer than winter 70* because summer air is wet and winter air is dry = There's more heat in water. I may have explained it incorrectly, and do understand how flawed an analogy my fireball example was, but the above was the basic concept that I was trying to say.
Quote: DocFace, you have stepped over into another area of thermal sciences here: convection heat transfer.
No arguement here. I think, like I explained to Nareed, that I have the idea, just not the tools to express it properly. I get the heat transfer. If I touch the concrete on my porch it feels cool, if I touch the metal leg of a chair on that porch it feels cold. They're both the same temp, but since metal conducts heat better (thereby sapping my heat faster) it "feels" colder. The same would work in reverse; if I set my house on fire and sprayed my porch with water, the concrete would steam but the chair leg would sizzle, since the metal would transfer the heat faster. Am I making sense and speaking truth? You can give a simple yes/no answer to this, or grade my closeness of correctness in a percentage, rather than trying to pound knowledge through my soggy noggin ;)
This just brought up another question, which I'd like to know before asking my next (if this is possible/not too much bother to explain). Nareed stated that temp does not equal heat. I always thought of "temp" as a measure of kintetic energy, and "heat" as how we perceive it. A short internet search seems to intermix these two, at times seeming to give the same definition for both of the terms. Is there an easy way to give me the scientific definition of the two, so I can ask my next question properly?
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November 5th, 2011 at 2:17:28 PM
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Well, the scientific/engineering definitions might get a little nerdy and likely wouldn't match what is in common usage anyway.
Start by considering "energy", then consider that energy may be within a particular "system" (body, collection of bodies, physical region, whatever) or it may be in the process of being transferred from one system to another. "Heat" is one of the two forms of energy that are transferred from one system to another. It is the energy that is transferred due to a difference in temperature (not yet defined explicitly). The other form of energy transfer is called "work", and it includes a lot of things we don't normally think of as work. I think that "heat" is properly defined as energy transferred to or from a system due to a temperature difference.
Defining "temperature" is a significant topic in the field of thermodynamics. As a practical matter, temperature is a measure of the thermal energy contained within a body ("internal energy") -- this is correct for ideal gases, incompressible liquids, and some other materials, I think, but for more general substances, you need to know more than the temperature to measure the internal energy. Temperature is still a major factor in measuring internal energy, even if there are other factors (such as pressure or other physical stresses) that get involved for many materials. For a first-cut, internet-forum discussion definition, you can work fairly well by defining temperature as the measure of internal energy per unit of mass. It is definitely different from "heat".
Start by considering "energy", then consider that energy may be within a particular "system" (body, collection of bodies, physical region, whatever) or it may be in the process of being transferred from one system to another. "Heat" is one of the two forms of energy that are transferred from one system to another. It is the energy that is transferred due to a difference in temperature (not yet defined explicitly). The other form of energy transfer is called "work", and it includes a lot of things we don't normally think of as work. I think that "heat" is properly defined as energy transferred to or from a system due to a temperature difference.
Defining "temperature" is a significant topic in the field of thermodynamics. As a practical matter, temperature is a measure of the thermal energy contained within a body ("internal energy") -- this is correct for ideal gases, incompressible liquids, and some other materials, I think, but for more general substances, you need to know more than the temperature to measure the internal energy. Temperature is still a major factor in measuring internal energy, even if there are other factors (such as pressure or other physical stresses) that get involved for many materials. For a first-cut, internet-forum discussion definition, you can work fairly well by defining temperature as the measure of internal energy per unit of mass. It is definitely different from "heat".
November 5th, 2011 at 3:11:21 PM
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OK, Doc. Let's see if I have a basic understanding of this.
I remember watching some space exploration show on discovery, and on the show they were showing some wild new materials created by NASA. One was something they were trying or already using to coat the outside of the shuttle. The host had a small brick of it on a plate, which he heated with a blow torch type device. After a good minute of blasting it, he removed the torch and it glowed red. He then immediately picked it up by unprotected hand.
Does this example kind of highlight heat vs temp? It seems, if I'm understanding correctly, that this brick would have a wicked high temp (was subject to 1,000*+ heat, glowed red) but had very low heat (little to no heat transfered to his hand) Is this a good "idiots way" of understanding this?
I remember watching some space exploration show on discovery, and on the show they were showing some wild new materials created by NASA. One was something they were trying or already using to coat the outside of the shuttle. The host had a small brick of it on a plate, which he heated with a blow torch type device. After a good minute of blasting it, he removed the torch and it glowed red. He then immediately picked it up by unprotected hand.
Does this example kind of highlight heat vs temp? It seems, if I'm understanding correctly, that this brick would have a wicked high temp (was subject to 1,000*+ heat, glowed red) but had very low heat (little to no heat transfered to his hand) Is this a good "idiots way" of understanding this?
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November 5th, 2011 at 5:07:34 PM
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Quote: FaceBut isn't that kind of what I was saying?
You cannot "kind of say" in science. Terminology has to be very precise. Hey, I once got thrown out of class for arguing a term with the chemistry teacher (I forget which). To his credit before the next class he apologized and told me I was right :)
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November 5th, 2011 at 9:18:28 PM
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I am not familiar with this material, so my reply involves a bit of speculation.Quote: FaceDoes this example kind of highlight heat vs temp? It seems, if I'm understanding correctly, that this brick would have a wicked high temp (was subject to 1,000*+ heat, glowed red) but had very low heat (little to no heat transfered to his hand)
I don't want to get into radiation heat transfer, visible spectrum of radiation, etc. Just leave it that if it was glowing red, then yes, it was at a rather high temperature.
I can think of two very plausible scenarios in which a material at very high temperature could be picked up by hand without injury. One way would be for the material to have a very low heat capacity per unit surface area, so that after it transferred a non-painful amount of energy to your hand, the temperature of the material dropped dramatically. This could be accomplished by a material with a very low density or a very low specific heat or both.
A second way would be for the material to have an extremely low thermal conductivity. In that case, the material in the immediate vicinity of where you touch it would transfer heat to your hand (presumably a non-painful amount), but the low thermal conductivity would prohibit additional energy from being transferred from other parts of the material to the spots where it is touching your hand. In that case, the energy of the body would be transferred to your hand very slowly, without injuring you.
My speculation is that this material exhibits both of those properties: low heat capacity and low thermal conductivity. Not much energy is required to get it to glow red hot, but it doesn't take much energy removal (to your hand) to drop the temperature again, and that energy is conducted very slowly to the spots where you touch. I think some materials with such properties include solid foams and porous ceramics, but I am not a materials scientist. (Are there foam-formed ceramics? I dunno.)
A material with those properties would be quite useful for space shuttle heat shields on re-entry. The atmospheric friction would heat the shield to a high temperature, the shield would glow, thereby radiating much of this energy into the darkness of space, and the energy that remained in the shield would not be conducted into the vehicle. Of course, the heat shield material would need to have a variety of other properties in order to survive in that role, including mechanical strengths and low thermal expansion. Otherwise, a collision with some wayward insulation during launch could break away a portion of the shield, leading to disaster later on re-entry.
November 5th, 2011 at 9:58:16 PM
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Quote: FaceAfter a good minute of blasting it, he removed the torch and it glowed red. He then immediately picked it up by unprotected hand.
Did he pick it up by the end that was glowing red, or by some other part? If the latter, then it's a very good insulator and doesn't conduct heat well.
Have you ever baked a cake? When you remove it from the oven if you touch the mold the cake is in, you'll get a nasty second degree burn (at least). If you touch the cake, it will merely feel warm. That's because the metal mold conducts heat extremely well, but the cake does so poorly.
It's a very simple concept. Have you ever seen people doing a fire-walk? That is, walking barefoot on hot, red charcoal. The coals are very hot indeed, but they are poor heat conductors, and the uppermost layer is mostly non-burning ash. Add to that the very extensive network of blood vessels on the sole of the human foot, plus the elevated heart rate from anxiety, and you can walk a couple of yards on them without burning yourself. That's old hat, BTW, and thoroughly debunked as a "mind over matter" or other mystical claims. but step barefoot on a lit cigarette and again you'll get a nasty burn.
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November 6th, 2011 at 12:08:07 AM
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Quote: DocI don't want to get into radiation heat transfer, visible spectrum of radiation, etc. Just leave it that if it was glowing red, then yes, it was at a rather high temperature.
Thank you for that ;) I'm not so much interested in this material as a topic, I only used it to try to understand the "heat vs temp" idea. But thank you anyway for the explanation. +1 to my intelligence =)
Quote: NareedDid he pick it up by the end that was glowing red, or by some other part? If the latter, then it's a very good insulator and doesn't conduct heat well.
It was a neat squarish rectangle (no "-ish" or "kinda" in science ;), maybe 2" x 3" x 3". Just a small little block. He picked it up rather delicately with thumb and forefinger and placed it into his open palm. It was still glowing red while in his palm and remained that way while he continued his little speech. Since it was still glowing red, I assume this fits more with Doc's second example...
Quote: DocA second way would be for the material to have an extremely low thermal conductivity. In that case, the material in the immediate vicinity of where you touch it would transfer heat to your hand (presumably a non-painful amount), but the low thermal conductivity would prohibit additional energy from being transferred from other parts of the material to the spots where it is touching your hand. In that case, the energy of the body would be transferred to your hand very slowly, without injuring you.
So, Doc says that since it was glowing red, it's safe to assume it had a high temperature. Just so I'm clear, is it also correct to say "it had low heat"? I'm thinking that temp is a measure of energy "stored", for lack of a better word, while heat is kinda (<~~can't help it, too ignorant to explain in a proper term) a measure of the energy released. That block had a high temp, proven by its red glow. It also had low heat, proven by its ability to be handled.
(I know my definition "measure of the energy released" may be poor, but I'm at a loss to explain myself properly. If you can translate my garble, does it seem like I'm at least getting the gist of this?)
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November 6th, 2011 at 2:47:12 AM
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Another concept to grasp with the temperature/heat thing is to take a glass of ice-water, which if it is pure would measure 32 degrees F. Leave it in a warm room and it will absorb heat to melt the ice, but never measure different than 32 degrees till all water. Place it in a freezer, and it will release energy, still properly considered heat, until completely frozen, all along never measuring colder than 32 degrees until totally frozen. Don't think it should be considered heat? Place a large enough container of cold water in your freezer and you will find it thaws out adjoining items while it freezes into ice.
So there is a quantity of energy that gets locked up into the work of releasing ice bonds. It takes a little thought to think of it as heat energy, since intuition wants to think of heat as something that always changes temperature. [edited]
So there is a quantity of energy that gets locked up into the work of releasing ice bonds. It takes a little thought to think of it as heat energy, since intuition wants to think of heat as something that always changes temperature. [edited]
the next time Dame Fortune toys with your heart, your soul and your wallet, raise your glass and praise her thus: “Thanks for nothing, you cold-hearted, evil, damnable, nefarious, low-life, malicious monster from Hell!” She is, after all, stone deaf. ... Arnold Snyder
November 6th, 2011 at 3:36:12 AM
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Quote: odiousgambitDon't think it should be considered heat?
Anything above zero Kelvin qualifies as possessing heat.
Quote:Place a large enough container of cold water in your freezer and you will find it thaws out adjoining items while it freezes into ice.
I'll do you one better :)
When I put together samples, sometimes I need to include frozen juice and fruit-flavored concentrates. This comes in thin, plastic bottle of one liter each. A typical batch includes, oh, ten to fifteen such bottles, each one frozen solid. At first I would label each (after scraping away whatever ice condensed on the surface), place them in individual bags and put them in a Styrofoam cooler full of ice.
This is a lot of labor, of course. Once I had to deliver them very near to the office, so I skipped bagging them and decided not to use any ice. As it turned out, I was kept waiting with my samples for nearly two hours, all the while fretting about the frozen samples. Well, they were colder than when I kept them on ice.
I realized, then than ice absorbs heat better than air. So when you take large volumes of frozen fluids and surround them with ice, the ice actually warms them up.
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November 6th, 2011 at 6:51:52 AM
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Not to be picky, Face, but you missed part of the earlier lesson (j/k). A body doesn't have "heat"; it has internal energy. "Heat" is energy that is in the process of being transferred to or from the body. Add heat to a body, you increase its internal energy; remove heat, and you reduce its internal energy. It does not contain "heat". OK, I realize that is nerdy terminology, but I'd hate to get too loose now and suffer the barrage.Quote: FaceSo, Doc says that since it was glowing red, it's safe to assume it had a high temperature. Just so I'm clear, is it also correct to say "it had low heat"? I'm thinking that temp is a measure of energy "stored", for lack of a better word, while heat is kinda (<~~can't help it, too ignorant to explain in a proper term) a measure of the energy released. That block had a high temp, proven by its red glow. It also had low heat, proven by its ability to be handled.
I said that temperature is an indicator of the internal energy of a body. I neglected to point out that there is more to it, particularly mass and specific heat (a property of the material). Suppose you put a 1 pound piece of hot aluminum into 1 pound of cool water and wait for them to arrive at a uniform temperature. (Side note: I assume the aluminum is not so hot that it boils the water.) The aluminum drops in temperature as it loses internal energy (as heat) to the water, which in turn increases in temperature as its internal energy increases. The amount of internal energy decrease by the aluminum is the same as the internal energy increase by the water. However, the aluminum will have a greater change in temperature than the water because the nature of the aluminum is different -- it has a lower specific heat. The temperature changes of the two materials would be even more different if the 1 pound of hot aluminum were placed into 100 pounds of cool water, even though the changes in internal energy would be the same amount (one a positive change and one a negative change).
Because of the issues of mass and specific heat, it is not really proper to say that a body at high temperature has a high internal energy (not "heat"). It just has a higher internal energy than that same body has at a lower temperature. There is also the issue that Odiousgambit pointed out without naming it -- latent heat. That is the internal energy increase (decrease) during boiling (condensation) or melting (freezing). These increases and decreases in internal energy do not show up as temperature changes but rather as phase changes, leading to the need for the term "latent heat", or the heat you can add or remove without having a temperature change. (Seems we might be getting into too many related topics all at the same time.)
November 6th, 2011 at 3:24:25 PM
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Thanks for your input, OG. I was aware of phase change, but it still gave me something to think of and keep in mind. Like Nareed, I've found ways to use this to my advantage. Say I need cold drink immediately, and the 12 pack was left on the counter, unrefrigerated. Rather than put it in the fridge or a cooler full of ice, I put it in a cooler filled with ice water. Ice cubes melt, which due to phase change means they're 32*. But due to their geometry, they only touch a very small portion of the cans surface area. Ice water should also be at 32* due to phase change, but it covers the entire surface area of the can. I find they cool much faster this way, even more so than putting them into the fridge or freezer.
No worries whatsover, Doc. I appreciate your patience and determination to make sure I've got this right (even if I repeatedly bungle it along the way). It's difficult seperating science fact from everday parlance, as OG pointed out, but the good news is I think I finally have a good understanding of this. Basically, although related, heat is not temp and temp is not heat. Temp is the measure of energy contained within, heat is a measure of energy transfered.
I also understood your specific heat and phase change examples, so things are looking up. Many things were learned this week, thanks to all. =) I'll let this simmer for now if anyone has any other comments, or would like to post their own topic...
Quote: DocNot to be picky, Face, but you missed part of the earlier lesson (j/k). A body doesn't have "heat"; it has internal energy. "Heat" is energy that is in the process of being transferred to or from the body. Add heat to a body, you increase its internal energy; remove heat, and you reduce its internal energy. It does not contain "heat". OK, I realize that is nerdy terminology, but I'd hate to get too loose now and suffer the barrage.
No worries whatsover, Doc. I appreciate your patience and determination to make sure I've got this right (even if I repeatedly bungle it along the way). It's difficult seperating science fact from everday parlance, as OG pointed out, but the good news is I think I finally have a good understanding of this. Basically, although related, heat is not temp and temp is not heat. Temp is the measure of energy contained within, heat is a measure of energy transfered.
I also understood your specific heat and phase change examples, so things are looking up. Many things were learned this week, thanks to all. =) I'll let this simmer for now if anyone has any other comments, or would like to post their own topic...
The opinions of this moderator are for entertainment purposes only.
November 6th, 2011 at 6:05:52 PM
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Quote: FaceSay I need cold drink immediately, and the 12 pack was left on the counter, unrefrigerated. Rather than put it in the fridge or a cooler full of ice, I put it in a cooler filled with ice water.
That's the fastest, sensible way to cool a drink without adding ice to it.
If you don't have iced water handy, place ice in the cooler and sprinkle it with slat so it melts. Instant, or nearly so, iced water.
Oh, the fastest, non-sensible way to cool down canned drinks is to spray them with a CO2 fire extinguisher. Gasses cool as they expand. The CO2 coming out of an extinguisher cools down so much it turns to CO2 snow, or dry ice as it's more commonly known. Of course, if you have liquid nitrogen...
Donald Trump is a fucking criminal
November 6th, 2011 at 7:38:04 PM
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Quote: FaceSay I need cold drink immediately, and the 12 pack was left on the counter, unrefrigerated. Rather than put it in the fridge or a cooler full of ice, I put it in a cooler filled with ice water.
When I was a kid in the 50's, most gas stations and
small businesses had the machine seen here, or a
variation of it. It was filled with water that was kept
at about 35 degrees and you slid the Coke down a
track to the end and pulled it up thru a mechanism
that let you get just one per nickel deposited. This
Coke was so cold, it would give you a brain freeze
in July. Man were they good. It was the old Coke
made with sugar, not the crap they have now made
with high fructose syrup.
"It's not called gambling if the math is on your side."
November 7th, 2011 at 1:53:01 AM
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Quote: EvenBobyou slid the Coke down a track to the end and pulled it up thru a mechanism
that let you get just one per nickel deposited.
I remember that part quite well, but in my neck of the woods they didnt seem to provide the cold water bath.
the next time Dame Fortune toys with your heart, your soul and your wallet, raise your glass and praise her thus: “Thanks for nothing, you cold-hearted, evil, damnable, nefarious, low-life, malicious monster from Hell!” She is, after all, stone deaf. ... Arnold Snyder
November 7th, 2011 at 10:08:07 AM
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I also remember these machines but not the cold water. The bottles were suspended from the track by their necks and an opener was needed to get the caps off. Kids used to open the bottles while they were still in the track, stick in a straw and get a free drink.
They probably grew up to be cheating card counters.
They probably grew up to be cheating card counters.
Many people, especially ignorant people, want to punish you for speaking the truth. - Mahatma Ghandi
November 11th, 2011 at 10:11:14 AM
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The spirit of this thread seeming to be approaching science from the vantage point of a dilettante, I will continue with that and ask for opinions on computer modeling as a scientific method. Now I do know something about The Scientific Method, which without looking it up is something like this: "form hypothesis, test it, use controls. Results and all aspects should be shared and subject to a forum. Peers should be able to duplicate results. " Computer modeling does not seem to fit with this. I guess my main concern is that there has to be bias built in to any 'test' and clearly tweaking would be going on. Also, how does one use a control? Finally, how do peers duplicate results, design their own program?
the next time Dame Fortune toys with your heart, your soul and your wallet, raise your glass and praise her thus: “Thanks for nothing, you cold-hearted, evil, damnable, nefarious, low-life, malicious monster from Hell!” She is, after all, stone deaf. ... Arnold Snyder
November 15th, 2011 at 2:07:10 PM
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I just noticed that no one had replied to your questions. Did you feel ignored and get your feelings hurt? :-)
Don't take my comments here as facts or even wannabe facts – they are just my opinions, and here is an opinion that is likely offensive to many computer modelers: I don't view computer models as a method of scientific research that tells you an answer. (Once the uproar and onslaught subsides, I will continue.)
(OK now, I can no longer hear the shouting.) I instead view computer modeling as a technique that helps to visualize and reformulate potential answers and explanations. If they lead to an explanation that seems particularly interesting and plausible, then physical investigations are necessary to establish that the explanation is real. Until then, there is only the framework for a theory. (Computer models are also extremely useful in analyzing or designing solutions based on known science, but here I am discussing coming up with something previously unknown.)
Many graduate students perform computer-model-based research programs leading to their theses and dissertations in both science and engineering. In my opinion, that research is useful in identifying directions in which future research might be productive. That is a very valuable role, but the models do not really answer the questions by themselves. Also, in my opinion, these "model" theses and dissertations are popular because they tend to be easier and much faster to complete than performing research with actual physical experiments.
I am completely forgetting the details of this anecdote, but I'll tell a little of it anyway. Thirty years or more ago, a graduate student developed a computer model to investigate a complex problem in fluid dynamics. (I should note that fluid dynamics involves complications to the extent that many graduate students consider it to be in the realm of black magic.) Well, this graduate student discovered a phenomenon that had never previously been described, and he called it the ________ effect, for which he inserted his own name.
As it turned out, he did not acquire the fame associated with Ernst Mach, Osborne Reynolds, Daniel Bernoulli, etc. Instead, after his dissertation was published, it was discovered that the "effect" was strictly the result of a programming error in his model. References to the ______ effect were subsequently used to ridicule both the new degree holder and his advisor and to point out the career dangers that arise from arrogance.
Don't take my comments here as facts or even wannabe facts – they are just my opinions, and here is an opinion that is likely offensive to many computer modelers: I don't view computer models as a method of scientific research that tells you an answer. (Once the uproar and onslaught subsides, I will continue.)
(OK now, I can no longer hear the shouting.) I instead view computer modeling as a technique that helps to visualize and reformulate potential answers and explanations. If they lead to an explanation that seems particularly interesting and plausible, then physical investigations are necessary to establish that the explanation is real. Until then, there is only the framework for a theory. (Computer models are also extremely useful in analyzing or designing solutions based on known science, but here I am discussing coming up with something previously unknown.)
Many graduate students perform computer-model-based research programs leading to their theses and dissertations in both science and engineering. In my opinion, that research is useful in identifying directions in which future research might be productive. That is a very valuable role, but the models do not really answer the questions by themselves. Also, in my opinion, these "model" theses and dissertations are popular because they tend to be easier and much faster to complete than performing research with actual physical experiments.
I am completely forgetting the details of this anecdote, but I'll tell a little of it anyway. Thirty years or more ago, a graduate student developed a computer model to investigate a complex problem in fluid dynamics. (I should note that fluid dynamics involves complications to the extent that many graduate students consider it to be in the realm of black magic.) Well, this graduate student discovered a phenomenon that had never previously been described, and he called it the ________ effect, for which he inserted his own name.
As it turned out, he did not acquire the fame associated with Ernst Mach, Osborne Reynolds, Daniel Bernoulli, etc. Instead, after his dissertation was published, it was discovered that the "effect" was strictly the result of a programming error in his model. References to the ______ effect were subsequently used to ridicule both the new degree holder and his advisor and to point out the career dangers that arise from arrogance.
November 15th, 2011 at 4:34:23 PM
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Nice read Doc. I also think modeling is great for providing direction, but limited in ways that physical experiments, and the resulting serendipidous results are not.
A luxury car maker is advertising that their crash simulation models use millions of data points, inferring that more is better. I guess it is cheaper than crashing a $50k+ car each time, but what will two million points of data tell you that 1 million won't?
Based on models prior to the twenty-first century, bumblebees should not be able to fly. The models had to be revised to account for observed phenomena.
A luxury car maker is advertising that their crash simulation models use millions of data points, inferring that more is better. I guess it is cheaper than crashing a $50k+ car each time, but what will two million points of data tell you that 1 million won't?
Based on models prior to the twenty-first century, bumblebees should not be able to fly. The models had to be revised to account for observed phenomena.
Simplicity is the ultimate sophistication - Leonardo da Vinci
November 15th, 2011 at 5:36:03 PM
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Quote: Docinstead, after his dissertation was published, it was discovered that the "effect" was strictly the result of a programming error in his model.
Didn't something similar happen with the Inflation model of the universe? Not quite an error, but that changing a parameter or two changed the outcome of the model so it looked nothing at all like the observations. I think this was explained mroe as bias; i.e. that the model was adjusted, not deliberately, to conform to observations.
Or something like that.
Donald Trump is a fucking criminal
November 15th, 2011 at 5:45:19 PM
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Quote: DocDid you feel ignored and get your feelings hurt? :-)
Well, I realized I shouldnt have attempted to revive the thread on Veteran's Day. We were a bit busy here. Glad you found it. Good story on the ___ effect!
the next time Dame Fortune toys with your heart, your soul and your wallet, raise your glass and praise her thus: “Thanks for nothing, you cold-hearted, evil, damnable, nefarious, low-life, malicious monster from Hell!” She is, after all, stone deaf. ... Arnold Snyder
November 15th, 2011 at 6:30:54 PM
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Quote: odiousgambit"form hypothesis, test it, use controls. Results and all aspects should be shared and subject to a forum. Peers should be able to duplicate results. " Computer modeling does not seem to fit with this.
I think, you guys are confusing theoretical science with experiment. The modeling fits the first part - forming of a hypothesis, and developing a theory. The theory should then match experimental results, ideally, make predictions, that are then confirmed with the experiment.
Imagine, Newton sitting under the tree, hit on his head with an apple, uttering F = GMm/R^2 ... That is the model he built. It can then be used to, for example, calculate the orbit of Mars, that one can observe, and confirm the model with experiment.
Where do computers come into this? Well, the science has gone a really long way forward since Newton, and most formulas aren't nearly as simple as E=mc^2. A lot of the time, you just can't find an analytical solution to the problem, and have to resort to modeling, not to substitute experimental results, but to calculate what results the experiment should be looking for.
Take the orbit of Mars example. You can solve the problem of the motion of two gravitating masses relatively easily, but even the 3-body problem is already too complex to be solved analytically, and if n is greater than three, you absolutely need a computer model to solve it. Once you use the model to compute the motion of such a complex system, you compare results with the observations as usual to validate the theory.
"When two people always agree one of them is unnecessary"
November 15th, 2011 at 7:00:42 PM
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Quote: weaselman... Once you use the model to compute the motion of such a complex system, you compare results with the observations as usual to validate the theory.
Exactly!
Unfortunately, far too many modelers feel the job is finished once they get their system of equations to converge stably. And for many systems and problems, figuring out a way to get "observations" can be exceedingly troubling, with actually getting them far beyond that on the difficulty scale.
In many complex problems (remember what I said about fluid dynamics?), neither an analytical solution nor a complete computer model of the system is currently plausible. Analytical study of the system can be carried only so far as identifying the governing system of equations and the controlling groups of variables. Knowing these enables a researcher to make some sense of experimental data and develop useful empirical relationships to explain or predict behavior of the system. Such "models" are critically important, but their application requires the experimental investigations.
November 15th, 2011 at 7:05:41 PM
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Quote: DocExactly!
Unfortunately, far too many modelers feel the job is finished once they get their system of equations to converge stably.
Well ... their job is indeed finished. A good theorist rarely (practically never) makes a good experimenter, and vice versa. Those are two very distinct and separate skill sets.
"When two people always agree one of them is unnecessary"
November 16th, 2011 at 1:43:42 PM
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Here's a question in this category that's been bugging me:
Why is flu seasonal? Why doesn't it circulate to the other hemisphere when things warm up, then return the next Fall?
Why is flu seasonal? Why doesn't it circulate to the other hemisphere when things warm up, then return the next Fall?
Simplicity is the ultimate sophistication - Leonardo da Vinci
November 16th, 2011 at 2:03:33 PM
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Quote: AyecarumbaHere's a question in this category that's been bugging me:
No smiley?
Quote:Why is flu seasonal? Why doesn't it circulate to the other hemisphere when things warm up, then return the next Fall?
Well, flu is a name that applies to many kinds of respiratory infections. The infamous Spanish Flu pandemic was likely a type of pneumonia. These days it can also mean the common cold.
What I know is that the flu/cold viruses survive best outside the body under certain conditions, like damp, cold air. Low levels of sunlight also help. Therefore it will be more prevalent during fall and winter than spring and summer. But an outbreak can happen any time. the Swine flu that broke in Mexico happened in the Spring (and that might have been a factor in why it wasn't more severe).
PSA: remember to wash or sanitize your hands often through flu season, and to keep them away from your nose, eayes, ears and mouth. Also don't sahre eating utensils with paople who may be sick. This is the best way to stave it off, but like a casino bet it's not an advantage paly. it's better than eating Vitamin C tablets for lunch and dinner.
Donald Trump is a fucking criminal
November 16th, 2011 at 3:05:01 PM
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There is actually no a uniformly accepted explanation for why flu is seasonal. Suggestions range from "people spend more time indoors in winter" or "kids don't go to school in summer" to "cold dry air helps propagation of the virus" or "viruses survive longer in the cold".
None of these explanations seems to be sufficient by itself, so, most likely, it is really a combination of factors.
This is actually the other way around. Washing hands does absolutely nothing against airborne viruses like influenza or common cold (no, it is not the same virus).
It does not mean, that washing hands is pointless, of course - it is still a good idea, because it helps to protect yourself from bacterial infections (as well as some viruses that can be picked up from the germs on your hands), just know that it does absolutely nothing against the flu.
Vitamin "C" on the other hand has been shown to boost the immune system, which is about the only protection you have against viruses, aside from vaccination.
None of these explanations seems to be sufficient by itself, so, most likely, it is really a combination of factors.
Quote:PSA: remember to wash or sanitize your hands often through flu season, and to keep them away from your nose, eayes, ears and mouth ... it's better than eating Vitamin C tablets for lunch and dinner.
This is actually the other way around. Washing hands does absolutely nothing against airborne viruses like influenza or common cold (no, it is not the same virus).
It does not mean, that washing hands is pointless, of course - it is still a good idea, because it helps to protect yourself from bacterial infections (as well as some viruses that can be picked up from the germs on your hands), just know that it does absolutely nothing against the flu.
Vitamin "C" on the other hand has been shown to boost the immune system, which is about the only protection you have against viruses, aside from vaccination.
"When two people always agree one of them is unnecessary"
November 16th, 2011 at 3:53:42 PM
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Good points made, I'll add a few of my own.
I think something can be said for your personal biology. For one, when it gets cold out, your body must use more energy than it's used to to keep you warm. Could that possibly weaken your system, making you more vulnerable to illness? Also, I can FEEL my body changing at this time of year, from mood, emotions, energy level, you name it. Perhaps this change also opens you up to more infections...
Another point I think makes a difference is disturbance. Often you'll hear of warning around a body of water when it's dredged, since stirring up all that mess luikewise stirs up pollutants in the soil. If you ever seen a bridge being riprapped or a creek bank being reconfigured, you'll often see a type of 'water fence' erected just downstream of the work, to slow the water and allow the stirred up mud to settle. Perhaps our HVAC systems cause the same problems. All the yuck in the ducts gets swooped up and sprayed upon our unsuspecting heads, and instead of air coming in from outside and washing away any contaminants, it is recycled over and over, constantly spraying us with bugs.
Like has been said, I don't think there's a golden gun, just a long list of little things that add up to winter misery.
I think something can be said for your personal biology. For one, when it gets cold out, your body must use more energy than it's used to to keep you warm. Could that possibly weaken your system, making you more vulnerable to illness? Also, I can FEEL my body changing at this time of year, from mood, emotions, energy level, you name it. Perhaps this change also opens you up to more infections...
Another point I think makes a difference is disturbance. Often you'll hear of warning around a body of water when it's dredged, since stirring up all that mess luikewise stirs up pollutants in the soil. If you ever seen a bridge being riprapped or a creek bank being reconfigured, you'll often see a type of 'water fence' erected just downstream of the work, to slow the water and allow the stirred up mud to settle. Perhaps our HVAC systems cause the same problems. All the yuck in the ducts gets swooped up and sprayed upon our unsuspecting heads, and instead of air coming in from outside and washing away any contaminants, it is recycled over and over, constantly spraying us with bugs.
Like has been said, I don't think there's a golden gun, just a long list of little things that add up to winter misery.
The opinions of this moderator are for entertainment purposes only.
November 16th, 2011 at 4:59:12 PM
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Quote: weaselmanThis is actually the other way around. Washing hands does absolutely nothing against airborne viruses like influenza or common cold (no, it is not the same virus).
Most contagion occurs from virus particles that are deposited on surfaces. Nothing floats in the air forever, virus or no virus. When thos einfected cough, sneeze and, to a lesser extent talk and breathe, they expell little droplets of water and mucus loaded with virus. These settle on surfaces and get picked up by your hands when you touch anything, then enter your body when you bring your hands to the eyes, ears, nose and mouth.
Therefore washing your hands helps a great deal.
Quote:Vitamin "C" on the other hand has been shown to boost the immune system, which is about the only protection you have against viruses, aside from vaccination.
The nose has a great deal of protection against viruses, from physicala barriers to the immune system. The same can be said of the bucal mucosa. And I guess msot people get enough vitamin C that taking supplments does nothign but waste money. A couple of glasses of orange juice, for example, should be enough. I take about 4 to 6 limes in the course of a normal day. That's plenty.
Donald Trump is a fucking criminal
November 16th, 2011 at 5:11:32 PM
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Quote: NareedMost contagion occurs from virus particles that are deposited on surfaces.
Depends. If you are talking about infectious disease in general, yes, that is true.
Influenza in particular? Nope. Airborne.
Quote:And I guess msot people get enough vitamin C that taking supplments does nothign but waste money.
That can be applied to anything. If you already take enough of something, supplementing it is pointless.
A couple of things that makes vitamin C particularly special in this respect, are that there is (almost) no such thing as too much of it, and it gets quickly run down by a starting infection. It means, that, even if you are taking enough vitamin C with your regular daily diet, you still want to bump it up even higher during flu season, because if you do catch the virus, you will need it all even before the first symptom occurs.
Quote:I take about 4 to 6 limes in the course of a normal day. That's plenty.
Yeah, it sounds like it is. Some people prefer a pill. It does not matter so much which form you take it in. Just know that it does help (a lot) protecting against viruses like flue.
"When two people always agree one of them is unnecessary"
November 16th, 2011 at 5:17:21 PM
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Quote: weaselmanDepends. If you are talking about infectious disease in general, yes, that is true.
Influenza in particular? Nope. Airborne.
If you sneeze inside a closed room, or an elevator, say, most viral particles will wind up on surfaces. Airborne means it travels through the air, not that it's only transmitted trhough the air.
Quote:A couple of things that makes vitamin C particularly special in this respect, are that there is (almost) no such thing as too much of it, and it gets quickly run down by a starting infection. It means, that, even if you are taking enough vitamin C with your regular daily diet, you still want to bump it up even higher during flu season, because if you do catch the virus, you will need it all even before the first symptom occurs.
That's why the treatment consists in lots of fluids, particualrly orange and grapefruit juice, and rest.
Donald Trump is a fucking criminal
November 16th, 2011 at 5:29:54 PM
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Quote: NareedIf you sneeze inside a closed room, or an elevator, say, most viral particles will wind up on surfaces. Airborne means it travels through the air, not that it's only transmitted trhough the air.
Everything travels through the air, if you throw it high enough. Airborne disease is one, transmitted through the air.
In theory, it is possible, that a particle, contaminated with a virus sticks to a surface, then moves to your hand, and then put into your nose and inhaled. However, if someone sneezed in the elevator you are riding, there are many orders of magnitude more infectious particles in the air than on the surfaces, you are many orders of magnitude more likely to inhale them, and they are many, many times more viable and long living than those that get stuck to a surface.
If you manage not to contract a virus by breathing the air in that elevator, it is very safe to say, that touching any of its surfaces won't harm you (not in terms of catching an airborne virus like flu anyway).
Quote:That's why the treatment consists in lots of fluids, particualrly orange and grapefruit juice, and rest.
No, that's not why. Lots of fluids is just means to fight dehydration caused by the fever, and rest is just always good.
And it's not really "treatment". There is no treatment for influenza, if you do catch it, you just have to wait for it to pass on its own.
"When two people always agree one of them is unnecessary"
November 16th, 2011 at 5:48:08 PM
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Quote: weaselmanIf you manage not to contract a virus by breathing the air in that elevator, it is very safe to say, that touching any of its surfaces won't harm you (not in terms of catching an airborne virus like flu anyway).
Fine. Don't wash your hands, then.
Quote:There is no treatment for influenza, if you do catch it, you just have to wait for it to pass on its own.
It's supportive treatment. It won't make much difference in how long you'll be sick, but it will help to keep you healthy otherwise.
At least you didn't recommend taking antibiotics...
Donald Trump is a fucking criminal
November 16th, 2011 at 6:38:53 PM
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Quote: Nareed
At least you didn't recommend taking antibiotics...
Yeah ... they are about as effective against the flu as washing your hands is.
"When two people always agree one of them is unnecessary"
November 16th, 2011 at 6:39:39 PM
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And the great thing is, Florida oranges and grapefruits and Mexican lemons and limes are in season now. And very good.Quote: NareedThat's why the treatment consists in lots of fluids, particualrly orange and grapefruit juice, and rest.
I have been eating a raw lemon every day, sometimes with a little sugar but often just as is. Surprisingly invigorating and good.
"Dice, verily, are armed with goads and driving-hooks, deceiving and tormenting, causing grievous woe." -Rig Veda 10.34.4
November 17th, 2011 at 2:29:50 PM
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OK, let's get gross with this. I subscribed to a lifestyle later made famous by Carlin in one of his skits, namely, if you subject yourself to enough nastiness you become impervious to all. I almost never wash my hands (except lately due to having a child), I don't wash fruits/veggies, I eat food well past it's expiration, let mayo sit out, whatever, eat raw egg products, eat undercooked meats including chicken, drink creek and lake water... and I (now) NEVER get sick. I mean, I get a sinus infection like clockwork everytime the seasons change, but I never get a cold, never get the flu, never get a stomach bug, nothing.
The last time I remember having a cold was about 7 years ago. The last time I got the flu was nearly 20 years ago. The last time I had stomach issues was also nearly 20 years ago, and it always happened after visiting a certain body of water (one I used to drink, and one I still drink to this day, but now, with no consequence)
Is there something to this, or is it just luck? Other than the "shame" of being gross, could it be better healthwise to be somewhat dirty as opposed to overly clean?
The last time I remember having a cold was about 7 years ago. The last time I got the flu was nearly 20 years ago. The last time I had stomach issues was also nearly 20 years ago, and it always happened after visiting a certain body of water (one I used to drink, and one I still drink to this day, but now, with no consequence)
Is there something to this, or is it just luck? Other than the "shame" of being gross, could it be better healthwise to be somewhat dirty as opposed to overly clean?
The opinions of this moderator are for entertainment purposes only.
November 17th, 2011 at 2:41:42 PM
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Quote: FaceIs there something to this, or is it just luck? Other than the "shame" of being gross, could it be better healthwise to be somewhat dirty as opposed to overly clean?
Our immune system gets activated by the presence of viruses. It produces targeted antibodies that are designed to wipe out the specific invaders, and "remembers" how to do it if exposed to the same invaders in the future. This is how innoculation works. I think, but do not know for certain, that our bodies are better at doing this when we are younger, than when we are older. This is why chicken pox in adults (then known as 'shingles') is so debilitating.
So, in that sense, it is better to be exposed to different things (that hopefully don't kill you first), is a good thing since you will eventually gain immunity to all the local "bugs".
I think you could still die if you went to the Phillipines and had a street cart "balut", since you're body is not accustomed to the local germs. Just a guess though.
Simplicity is the ultimate sophistication - Leonardo da Vinci
November 17th, 2011 at 3:05:49 PM
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Quote: AyecarumbaOur immune system gets activated by the presence of viruses. It produces targeted antibodies that are designed to wipe out the specific invaders, and "remembers" how to do it if exposed to the same invaders in the future. This is how innoculation works. I think, but do not know for certain, that our bodies are better at doing this when we are younger, than when we are older. This is why chicken pox in adults (then known as 'shingles') is so debilitating.
Indeed, I am familiar with innoculation, but I'm not sure how it pertains to me. I mean, just because I exposed myself to the bugs of the past shouldn't mean I'm impervious to the bugs of the future, if future bugs are different. And yes, youth is better than age in this regard, but it seems I'm better off as I age. I guess I'm wondering if your immune system can be worked out, given some muscle, since it seems mine has. We know things can improve it; good general health, Vitamin C, excersize...can working it out directly by exposing yourself to pathogens actually make a difference? I don't mean specifically like a flu shot, but just a general intake of all sorts of yuck. Kind of like those snake handlers - if you take just a tick of neurotoxic venom over and over, you build up a resistance to ALL neurotoxic venom. Think there's something to this?
Quote: AyecarumbaI think you could still die if you went to the Phillipines and had a street cart "balut", since you're body is not accustomed to the local germs. Just a guess though.
I'm pretty sure you're right. In fact, I think that's exactly what the 'sick lake' was. It wasn't part of my normal exposure, and the lake was quite dirty and heavily developed, with a lot of runoff from farms and households. I'm sure the bacterial levels were such that that's what made me sick, but repeated exposure has made me immune to it. Used to be I got quite sick after every visit, but I went there probably 20 times this year and was right as rain. Doesn't mean I'll be patronizing the street vendors of Calcutta, but it seems you can kind of condition yourself against certain things.
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November 17th, 2011 at 3:44:22 PM
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Quote: Facecan working it out directly by exposing yourself to pathogens actually make a difference? I don't mean specifically like a flu shot, but just a general intake of all sorts of yuck. Kind of like those snake handlers - if you take just a tick of neurotoxic venoom over and over, you build up a resistance to ALL neurotoxic venom. Think there's something to this?
There's a whole system known as homeopathic medicine that is based on exactly what you are getting at. Small bits of "nastiness" will stiimulate your body's natural systems to grow immune to the particular baddy, as well as others that produced similar symptoms. A lot of quackery, but perhaps some truth. The practice has been formalized for more than 200 years. I'd still refrain from wiping my eyes after touching chips in any casino though.
Simplicity is the ultimate sophistication - Leonardo da Vinci
