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when we push a wall and are unable to move it where does the energy goes —The preceding unsigned comment was added by 59.161.1.40 ( talk)
-- Light current 00:19, 13 January 2007 (UTC)
edcon
Is there a list of materials that gallium combines with or corrodes?
What are good sources to order chemical supplies from? Suppliers similar to sigma aldrich, fisher sci, etc.
I am looking for a supplier that can give me the best price on a certain metal. I live in the US and have looked at Sigma and Aldrich but I wanted to shop around a little to see what other purities/prices others are offering.
Two unrelated questions about my eyes: 1. Is there anything I can do to make the white part whiter?
2. How does squinting help me read a little farther when I don't wear my glasses?
I first read about the analogy of the frog in boiling water in the book The Story of B, then I saw the analogy again in the film An Inconvenient Truth. The analogy is that if the frog is placed in a pot of boiling water, it will jump right out. However, if the frog is placed into a pot of room-temperature water, and the water is slowly increased to its boiling point, the frog will boil to death. The environmental plight of humanity has been compared to this. What is the origin of this analogy? If this does not apply to science, please move wherever necessary. — Erik ( talk • contrib) - 02:45, 13 January 2007 (UTC)
There is a similar effect I've observed myself, you can close a pair of pliers slowly on a wasp. Quick movements will scare them off, but not slow movements. Don't try this at home ! StuRat 05:20, 15 January 2007 (UTC)
Question - Would watching a good quality DVD movie be clearer in seeing things around us in real life? If you understand what i'm talking about. I was just wondering because when you look around a room or something you have a small intereference of colour or patterns from looking at something bright to looking at something darker but we're so used to it that we don't really notice it, but it's still there. But if you look at a T.V. screen you don't get that interference. So does that mean watching something clear like a DVD would appear clearer than just looking around in real life? It's a hard question to explain, but I hope most people understand what i'm getting at.
Not if you attempt to reproduce the normal image on DVD. There is, however, some processing that can be shown on DVD that you can't see directly. An obvious case would be including IR and/or UV wavelengths shifted into visible colors. The contrast and brightness can also be manipulated to avoid blinding you (most monitors couldn't do that anyway), and to avoid having anything too dim to see. StuRat 05:11, 15 January 2007 (UTC)
Why are ampules still used for some pharmaceuticals? They are very inconvenient - the drug has to be filtered before use, and sometimes they don't crack open the way they are supposed to. The vast majority of drugs use a vial with a rubber stopper, which is convenient for single or multi-use. -- Joelmills 04:49, 13 January 2007 (UTC)
Thanks for all the responses. I will refer my annoyed technicians to this page. -- Joelmills 22:21, 13 January 2007 (UTC)
This must be an exceptionally easy question for somebody here: how is the distance and age of stars calculated? I understand the red shift can measure the speed at which a star is moving away (speed of universe's expansion) but can it also be used to measure the stars distance from us? I thought maybe it was measured using parallax, but apparently the interstellar distances involved are so huge that this doesn't work. -Kelly
—carry out investigation of the relationship between lenght of a metallic conductor e.g nichrome wire and its resistance — Preceding unsigned comment added by 89.101.116.77 ( talk)
Some of our posters are so resistant to doing their own homework that the longer we insist, the less we get through and the more heated the discussion becomes (depending on the material, of course). StuRat 04:56, 15 January 2007 (UTC)
Does anyone know how this SMPD (Single Carrier Modulation Photo Detector) sensor that everyone's talking about works? The planet82 FAQ [2] looks to me more like a collection of buzzwords like nanotech, quantum tech etc rather then containing much useful info. I admit I've only done very brief searches so feel free to ignore me. I didn't even read their FAQ properly just browser through it Nil Einne 13:55, 13 January 2007 (UTC)
Simple enough, are gamma rays a part of solar radiation?
N.B. As I mentioned above, you can infer the sun emits gamma rays from a caption in that article:
We can presume from the caption that the sun does emit gamma rays other wise it will say something like "Surprisingly, the Moon emits gamma rays even though the sun does not) Nil Einne 13:53, 14 January 2007 (UTC)
...and does the Moon emit gamma rays or simply reflect them ? StuRat 04:51, 15 January 2007 (UTC)
I was raised in the dying days of vinyl, suffered through the Cassette tape, initially liked CDs, and have now begun downloading mainly classical recordings from iTunes. In that process I've seen the artwork, the drama, the visceral presence of the LP diminish into ghostly mp3 files and the occasional pdf attachment. In other words, I've been sandbagged into thinking that, despite getting less and less for the money, I'm somehow getting a superior product. And recently I learned that iTunes compresses audio files down to some certain rate, and that some aspects of the recording are lost in the process. I read through Compression artifacts but remain curious if someone can explain what, in general, may be getting lost in the journey from iTunes to my computer, and what a reasonably close listen to the CD v. the download might reveal, on, for example, a very recently released Deutsche Grammophon recording. Wolfgangus 17:28, 13 January 2007 (UTC)
Sounds minimal; not as drastic as I'd imagined. Thanks, Edison. Wolfgangus 00:55, 14 January 2007 (UTC)
On that note, the subjectivity of transparency you're referring to will certainly favor me, if for no other reason my hearing isn't what it used to be. Thanks for the further input. Wolfgangus 09:58, 14 January 2007 (UTC)
what is the prportional limit of steal48?σy —Preceding unsigned comment added by 196.205.218.36 ( talk • contribs) 18:36, 13 January 2007
are they any good for undoing girls' bras? —Preceding unsigned comment added by 86.142.11.215 ( talk • contribs) 19:02, 13 January 2007
Would an air purifier with a HEPA filter help clean the air of the outgassing (smell and possible chemicals) caused by newly opened memory foam? Thanks. -- Win777 19:25, 13 January 2007 (UTC)
Just let it air out for a few days in a garage or someplace that's easily ventilated before you use it. (I don't know why the factory can't be bothered to do this for you.) StuRat 04:43, 15 January 2007 (UTC)
If entropy is energy, what is the distinction? Is energy limitless while entropy is a word to describe a measurement over time? Looking back, was there limitless energy on earth and now we're looking at the temp of the ice in the glass becoming closer to the temp of the room in terms of entropy? How does any of this reverse global warming? 68.73.2.117 21:51, 13 January 2007 (UTC)
Introduction to entropy may have clues. -- Light current 23:15, 13 January 2007 (UTC)
Indeed, it sounds very grave. Nevertheless, the potential exists (until such time as you imagine) for the ice cube to be an ice cube if we can agree we like ice cubes and want them for TGIF parties, if there is such a thing any more. And while some may prefer room temperature beverages (no argument there) if we are losing polar ice caps -- couldn't we just make a huge white covering to reflect all that solar energy????? 68.73.2.117 22:50, 14 January 2007 (UTC)
Can it be practiced without thinking of a word to descsribe the image? If anxiety is word-related, wouldn't it be better to not use words... Say, if you're hearing your heart valves open and shut, can you redirect the thought to an Allis-Chalmers WD45 or the Dahli Lama and not feel panicky? 68.73.2.117 21:57, 13 January 2007 (UTC)
It isn't always better to think without words though, I do that a lot and find it difficult to write about what I am thinking :) You could instead think about being calm :) Hidden secret 7 11:46, 14 January 2007 (UTC)
Perhaps this is a philosophical question like which comes first the chicken or the egg, but I'm wondering if anxiety (eg the somatic parts that are distressing) is CAUSED by thought... Too much left-hemisphere... And my question is, well, how CAN you visualize ANYthing without verbal (left brain) input? Is it possible? And don't tell me "it depends" ") 68.73.2.117 22:53, 14 January 2007 (UTC)
"Thinking about being calm" and actually experiencing calmness are quite different things. The former would necessarily involve words, imo. The latter might be induced by visualising, or being in, surroundings that are calm, safe and pleasant. JackofOz 02:44, 15 January 2007 (UTC)
How far, in miles, can you possibly be from home whilst remaining on the Earth's surface? Stuarthill 22:37, 13 January 2007 (UTC)
Science desk | ||
---|---|---|
< January 12 | << Dec | January | Feb >> | January 14 > |
Welcome to the Wikipedia Science Reference Desk Archives |
---|
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
when we push a wall and are unable to move it where does the energy goes —The preceding unsigned comment was added by 59.161.1.40 ( talk)
-- Light current 00:19, 13 January 2007 (UTC)
edcon
Is there a list of materials that gallium combines with or corrodes?
What are good sources to order chemical supplies from? Suppliers similar to sigma aldrich, fisher sci, etc.
I am looking for a supplier that can give me the best price on a certain metal. I live in the US and have looked at Sigma and Aldrich but I wanted to shop around a little to see what other purities/prices others are offering.
Two unrelated questions about my eyes: 1. Is there anything I can do to make the white part whiter?
2. How does squinting help me read a little farther when I don't wear my glasses?
I first read about the analogy of the frog in boiling water in the book The Story of B, then I saw the analogy again in the film An Inconvenient Truth. The analogy is that if the frog is placed in a pot of boiling water, it will jump right out. However, if the frog is placed into a pot of room-temperature water, and the water is slowly increased to its boiling point, the frog will boil to death. The environmental plight of humanity has been compared to this. What is the origin of this analogy? If this does not apply to science, please move wherever necessary. — Erik ( talk • contrib) - 02:45, 13 January 2007 (UTC)
There is a similar effect I've observed myself, you can close a pair of pliers slowly on a wasp. Quick movements will scare them off, but not slow movements. Don't try this at home ! StuRat 05:20, 15 January 2007 (UTC)
Question - Would watching a good quality DVD movie be clearer in seeing things around us in real life? If you understand what i'm talking about. I was just wondering because when you look around a room or something you have a small intereference of colour or patterns from looking at something bright to looking at something darker but we're so used to it that we don't really notice it, but it's still there. But if you look at a T.V. screen you don't get that interference. So does that mean watching something clear like a DVD would appear clearer than just looking around in real life? It's a hard question to explain, but I hope most people understand what i'm getting at.
Not if you attempt to reproduce the normal image on DVD. There is, however, some processing that can be shown on DVD that you can't see directly. An obvious case would be including IR and/or UV wavelengths shifted into visible colors. The contrast and brightness can also be manipulated to avoid blinding you (most monitors couldn't do that anyway), and to avoid having anything too dim to see. StuRat 05:11, 15 January 2007 (UTC)
Why are ampules still used for some pharmaceuticals? They are very inconvenient - the drug has to be filtered before use, and sometimes they don't crack open the way they are supposed to. The vast majority of drugs use a vial with a rubber stopper, which is convenient for single or multi-use. -- Joelmills 04:49, 13 January 2007 (UTC)
Thanks for all the responses. I will refer my annoyed technicians to this page. -- Joelmills 22:21, 13 January 2007 (UTC)
This must be an exceptionally easy question for somebody here: how is the distance and age of stars calculated? I understand the red shift can measure the speed at which a star is moving away (speed of universe's expansion) but can it also be used to measure the stars distance from us? I thought maybe it was measured using parallax, but apparently the interstellar distances involved are so huge that this doesn't work. -Kelly
—carry out investigation of the relationship between lenght of a metallic conductor e.g nichrome wire and its resistance — Preceding unsigned comment added by 89.101.116.77 ( talk)
Some of our posters are so resistant to doing their own homework that the longer we insist, the less we get through and the more heated the discussion becomes (depending on the material, of course). StuRat 04:56, 15 January 2007 (UTC)
Does anyone know how this SMPD (Single Carrier Modulation Photo Detector) sensor that everyone's talking about works? The planet82 FAQ [2] looks to me more like a collection of buzzwords like nanotech, quantum tech etc rather then containing much useful info. I admit I've only done very brief searches so feel free to ignore me. I didn't even read their FAQ properly just browser through it Nil Einne 13:55, 13 January 2007 (UTC)
Simple enough, are gamma rays a part of solar radiation?
N.B. As I mentioned above, you can infer the sun emits gamma rays from a caption in that article:
We can presume from the caption that the sun does emit gamma rays other wise it will say something like "Surprisingly, the Moon emits gamma rays even though the sun does not) Nil Einne 13:53, 14 January 2007 (UTC)
...and does the Moon emit gamma rays or simply reflect them ? StuRat 04:51, 15 January 2007 (UTC)
I was raised in the dying days of vinyl, suffered through the Cassette tape, initially liked CDs, and have now begun downloading mainly classical recordings from iTunes. In that process I've seen the artwork, the drama, the visceral presence of the LP diminish into ghostly mp3 files and the occasional pdf attachment. In other words, I've been sandbagged into thinking that, despite getting less and less for the money, I'm somehow getting a superior product. And recently I learned that iTunes compresses audio files down to some certain rate, and that some aspects of the recording are lost in the process. I read through Compression artifacts but remain curious if someone can explain what, in general, may be getting lost in the journey from iTunes to my computer, and what a reasonably close listen to the CD v. the download might reveal, on, for example, a very recently released Deutsche Grammophon recording. Wolfgangus 17:28, 13 January 2007 (UTC)
Sounds minimal; not as drastic as I'd imagined. Thanks, Edison. Wolfgangus 00:55, 14 January 2007 (UTC)
On that note, the subjectivity of transparency you're referring to will certainly favor me, if for no other reason my hearing isn't what it used to be. Thanks for the further input. Wolfgangus 09:58, 14 January 2007 (UTC)
what is the prportional limit of steal48?σy —Preceding unsigned comment added by 196.205.218.36 ( talk • contribs) 18:36, 13 January 2007
are they any good for undoing girls' bras? —Preceding unsigned comment added by 86.142.11.215 ( talk • contribs) 19:02, 13 January 2007
Would an air purifier with a HEPA filter help clean the air of the outgassing (smell and possible chemicals) caused by newly opened memory foam? Thanks. -- Win777 19:25, 13 January 2007 (UTC)
Just let it air out for a few days in a garage or someplace that's easily ventilated before you use it. (I don't know why the factory can't be bothered to do this for you.) StuRat 04:43, 15 January 2007 (UTC)
If entropy is energy, what is the distinction? Is energy limitless while entropy is a word to describe a measurement over time? Looking back, was there limitless energy on earth and now we're looking at the temp of the ice in the glass becoming closer to the temp of the room in terms of entropy? How does any of this reverse global warming? 68.73.2.117 21:51, 13 January 2007 (UTC)
Introduction to entropy may have clues. -- Light current 23:15, 13 January 2007 (UTC)
Indeed, it sounds very grave. Nevertheless, the potential exists (until such time as you imagine) for the ice cube to be an ice cube if we can agree we like ice cubes and want them for TGIF parties, if there is such a thing any more. And while some may prefer room temperature beverages (no argument there) if we are losing polar ice caps -- couldn't we just make a huge white covering to reflect all that solar energy????? 68.73.2.117 22:50, 14 January 2007 (UTC)
Can it be practiced without thinking of a word to descsribe the image? If anxiety is word-related, wouldn't it be better to not use words... Say, if you're hearing your heart valves open and shut, can you redirect the thought to an Allis-Chalmers WD45 or the Dahli Lama and not feel panicky? 68.73.2.117 21:57, 13 January 2007 (UTC)
It isn't always better to think without words though, I do that a lot and find it difficult to write about what I am thinking :) You could instead think about being calm :) Hidden secret 7 11:46, 14 January 2007 (UTC)
Perhaps this is a philosophical question like which comes first the chicken or the egg, but I'm wondering if anxiety (eg the somatic parts that are distressing) is CAUSED by thought... Too much left-hemisphere... And my question is, well, how CAN you visualize ANYthing without verbal (left brain) input? Is it possible? And don't tell me "it depends" ") 68.73.2.117 22:53, 14 January 2007 (UTC)
"Thinking about being calm" and actually experiencing calmness are quite different things. The former would necessarily involve words, imo. The latter might be induced by visualising, or being in, surroundings that are calm, safe and pleasant. JackofOz 02:44, 15 January 2007 (UTC)
How far, in miles, can you possibly be from home whilst remaining on the Earth's surface? Stuarthill 22:37, 13 January 2007 (UTC)