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We are conducting an experiment in hydrolysis with various electrolytes, anodes and cathodes. Before getting started we would like to clear something up. Since platinum is used as a catalyst to assist chemical reactions which is safer to use in the production of hydrogen and oxygen gas (which might be together in a beaker as they are liberated through the process of electrolysis), a carbon rod or a platinum rod? 71.100.8.252 00:11, 22 April 2007 (UTC)
I was gardening today and had noticed a silvery coating on some old pieces of bark....then later I notice of silvery trail reflecting in the sun, and on inspection saw it was a snail leaving a slimy, beautiful trail behind him....is this common? —The preceding unsigned comment was added by 70.41.134.125 ( talk) 00:50, 22 April 2007 (UTC).
i know you can demagnetise a magnet with an impact but if i need to put a magnet in something that will recive impacts (average 10 to 20 pounds force), if i try to dampen the impact with a layer of rubber or something better would it be easy or at least possible to lower it enough to not any magnetic strenght?
also if that changes anything, the magnet needs to be in a magnetic fiels repulsing it —The preceding unsigned comment was added by 216.113.99.21 ( talk) 05:05, 22 April 2007 (UTC).
I doubt it matters much whether the magnet is being repelled by another at the time of the impact - but even a small amount of cushioning will certainly help immensely. Whether it helps enough in your application depends a lot on the nature of the magnet you are using - the rate of decelleration of the mass hitting the magnet - and probably a whole bunch of other things besides. You could perhaps consider using an electromagnet - so long as it's not mechanically damaged, it would be completely resistant to impacts. SteveBaker 05:13, 22 April 2007 (UTC)
it cant be an electromagnet be an electromagnet , what kind of materials would be the best?
the cheapest possible
no, the second most expencive is usually best.
what are specified requerment for cenemahall in india sp U.P. Mainly distance of screen from first row ,gap btween seat rows,no.exhust fans,toilets,entery and exit gates etc as per the person capicity. —The preceding unsigned comment was added by Rajharshchauhan ( talk • contribs) 07:58, 22 April 2007 (UTC).
In chemistry the concentration of a species A is denoted by , but for chemical activity the square brackets should be replaced by curly brackets - {A}. How can the square brackets in math expressions such as the one below be replaced by curly brackets, given that curly brackets have a special significance in the math system?
Petergans 12:15, 22 April 2007 (UTC)
Meta probably describes it somewhere: meta:Help:Displaying a formula. The Wikipedia:Help desk might have some other tips. -- HappyCamper 13:46, 22 April 2007 (UTC)
If I connect a DC power source to an AC transformer, what happens?-- 172.131.238.148 12:38, 22 April 2007 (UTC)
I know this is a huge question, but I'm just looking for a ballpark figure. I'm not talking about frozen meat or meat in pre-packaged food (although I'm curious about those as well) -- I'm just looking for any information about how long ago the meat from the packaged meat counter was slaughtered. Anyone know? Days, weeks... months? Thanks in advance! - Quasipalm 16:17, 22 April 2007 (UTC)
This is one of the symptoms of some kidney problem (I don't remember the finer details) that a family member's cat has been diagnosed with. Am I correct in thinking that the cat will be in agony every time he urinates (AFAIK, uric acid forms a very sharp crystalline structure)? He apparently holds on for almost a day between pisses - which would make sense if this were the case... -- Kurt Shaped Box 16:17, 22 April 2007 (UTC)
I would like to know if there are any materials that are uv sensite (not light sensetive). A material that, when exposed to a certain amount of uv light, will react in some way. It can either be to change color or to change shape, form or size.
Thank You 17:29, 22 April 2007 (UTC)~ Tertius F.
Hi
I'm a noob so that's why im doing it like this.
The thing is, the uv sensitive material I'm refering to should be something in the line of AgCl or something like that. I know AgCl is used in photo's, not that Im looking for the same reaction(coping of an image, rather the color change properties). The project Im working on needs at least one example of a substance that will change color after a certain amount of time in the sun (uv rays). Maybe some sort of silver halide that one can put in paint that darkens after a certain amouth of exposure to uv rays?
The problem is, it should react to the uv rays but not the light.
Or... Is there an invention that can measure uv rays like the radion patches that people wear who work in nuclear facilities. Something that detects uv rays and can give an indication according to how much rays it has absorbed?
Thanx again T.F —The preceding unsigned comment was added by 196.207.47.60 ( talk) 18:54, 22 April 2007 (UTC).
What I mean is, that it should react to UVA or UVB rays. The other possibility is if the material in question were to be able to react to light in the same amount of time that it absorbes uv rays. sort of like Time/Light = Time/UV rays. (some strange formula, i know)
The problem is, that lets say its paint on a wall, one day it will take the wall 3h to change color, and other days it will take 6h, just as long as its able to indicate that the paint has absorbed a certain amount of uv rays.
Thanx it help a lot. Not exactly what I had in mind but I can see it working in my project. You have been a great help.
Cheers T.F
There was a strange insect fluttering round my room the other night, and I have no idea what it was. I got a photo of it when it was sitting beside my laptop - for the purposes of scale, the green thing is the plug on my mouse, and it's about 1 1/4 inches long. It didn't buzz at all (just clattered a bit against the wall as it flew), and didn't seem distressed by my being there. I've googled phrases like "picture guide to insects" and had a flick through the article Insect (and related articles too), but can't find anything helpful - does anyone know what this thing is? I'm in southern England at the moment, if that's any help. -- ZsigE 20:05, 22 April 2007 (UTC)
Can you tell me if there are any contraindications or interactions from/with other meds. or herbs? I have looked on many cites including wikipedia. I can't find any thing concerning interactions or contraindications. Thank you curlyhorse
(as a start, the usual spelling is "Gymnema sylvestre") I would call your physician's attention to [2] "DrugDigest is the consumer health and drug information website of Express Scripts, Inc. (ESI), the nation's largest independent pharmacy benefit manager (PBM). Through its corporate relationships, ESI designs and manages prescription drug plans.... The goal of DrugDigest is to provide ESI members and the public with the information they need to lead healthier lives. " it's a professionally responsible source that includes scientific references. I consider it appropriate for librarians to give references to sources of reliable information, though not to provide medical advice. DGG 03:40, 23 April 2007 (UTC)
title- nuclear physics question-explain what would happen in a nuclear reactor if the coolant fluid leaked out of the core? —The preceding unsigned comment was added by 82.29.69.23 ( talk) 20:50, 22 April 2007 (UTC).
I'm assuming you mean primary coolant. In my understanding, nuclear reactors emit neutrons that are either "fast" or "slow". In some designs, the coolant is the moderator and turns the useless fast neutrons into slow ones. Therefore, if the primary coolant is removed, there are not enough slow neutrons to sustain the reaction and the core cools. Loss of secondary coolant may result in problems however. In other designs, the coolant is not the moderator and loss of coolant and moderator results in thermal runaway. -- Tbeatty 04:03, 23 April 2007 (UTC)
I asked this question on the humanities desk and it was suggested I ask it here also.
Ok, so we base out mathematics on axioms, things we accept without proof (such as one plus one equals two). If we accept something without proof, it is a philosophy. So wouldn't that make all of math a philosophy? That would be alright, it is just that we use math as the language of science. So wouldn't that make all our science equations written in math just a philosophy? Just our interpretation of the universe? I suppose this would supported by the fact that quantum mechanics has many different interpretations, and you can even take classes on the philosophy of quantum mechanics [3]. Isn't this kind of a big deal that all of our science may not be leading us to the reality, but only one interpretation of it? Imaninjapirate talk to me 22:06, 22 April 2007 (UTC)
You are asking about a lot of things. Basically you are asking:
First of all, there is no such thing as a singular Mathematics. Mathematics consists of a collection of diverse mathematical concepts. Some of the mathematical concepts are independent of other mathematical concepts.
Second, mathematical concepts are just like a game. It has rules. The rules are made up by humans. New mathematical concepts are made up all the time.
However, not all mathematical concepts survive into the future. Countless mathematical concepts have been abandon by mathematicians. You do not read or come across these abandon mathematical concepts because they are NOT taught in school.
Instead what you are taught in school/university are those mathematical concepts that have survived the passage of time. Thus these concepts worked and are useful in real life. In short there is evolution in mathematical concepts, they are subjected to natural selection by mathematicians.
That's why maths "works" in real life. Because those mathematical concepts that "did not work" has not survived.
202.168.50.40 01:45, 23 April 2007 (UTC)
The difference between philosophy and science is its testability. All scientific hypothesis is testable by definition, including 1+1=2. Philosophy is not defined by it's testability. Theories of God, goodness, utility, etc, are all fundamentally untestable. When philosophy is testable it becomes science, and when science becomes untestable it is philosophy. -- Tbeatty 02:50, 23 April 2007 (UTC)
Well, aren't those things at least partially testable? I mean this in the sense of narrowing down the answers in a multiple-choice problem:
"What is [indiscernible number]+[indiscernible number]?"
a. £ b. cheese c. 4 d. 6
To say that something is discretely "testable" or "untestable" is mistaken. There are degrees of certainty, and in my example problem, it is quite clear that a and b are NOT the correct answers. This can be tested (albeit non-physically) with the following sort of logic:
So the difference between science and philosophy is the method of testing. Philosophical notions, just like scientific theories, are used to explain. But the key here is the testing itself. Philosophy uses pure logic to test its notions, while science uses experimentation. Something like, for instance, a proof of God, can be shown to be false. This is what happened with the Ontological argument. The consensus of contemporary philosophers is that the argument is fallacious. The only difference is that there is much less to test. I personally see nothing different between using a Modus ponens to prove something, or to measure it in a laboratory.-- Kirby♥ time 10:36, 24 April 2007 (UTC)
I was wondering if it is possible to rip a shark's gills with your hands, what do ya think? Bastard Soap 22:07, 22 April 2007 (UTC)
Science desk | ||
---|---|---|
< April 21 | << Mar | April | May >> | April 23 > |
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. |
We are conducting an experiment in hydrolysis with various electrolytes, anodes and cathodes. Before getting started we would like to clear something up. Since platinum is used as a catalyst to assist chemical reactions which is safer to use in the production of hydrogen and oxygen gas (which might be together in a beaker as they are liberated through the process of electrolysis), a carbon rod or a platinum rod? 71.100.8.252 00:11, 22 April 2007 (UTC)
I was gardening today and had noticed a silvery coating on some old pieces of bark....then later I notice of silvery trail reflecting in the sun, and on inspection saw it was a snail leaving a slimy, beautiful trail behind him....is this common? —The preceding unsigned comment was added by 70.41.134.125 ( talk) 00:50, 22 April 2007 (UTC).
i know you can demagnetise a magnet with an impact but if i need to put a magnet in something that will recive impacts (average 10 to 20 pounds force), if i try to dampen the impact with a layer of rubber or something better would it be easy or at least possible to lower it enough to not any magnetic strenght?
also if that changes anything, the magnet needs to be in a magnetic fiels repulsing it —The preceding unsigned comment was added by 216.113.99.21 ( talk) 05:05, 22 April 2007 (UTC).
I doubt it matters much whether the magnet is being repelled by another at the time of the impact - but even a small amount of cushioning will certainly help immensely. Whether it helps enough in your application depends a lot on the nature of the magnet you are using - the rate of decelleration of the mass hitting the magnet - and probably a whole bunch of other things besides. You could perhaps consider using an electromagnet - so long as it's not mechanically damaged, it would be completely resistant to impacts. SteveBaker 05:13, 22 April 2007 (UTC)
it cant be an electromagnet be an electromagnet , what kind of materials would be the best?
the cheapest possible
no, the second most expencive is usually best.
what are specified requerment for cenemahall in india sp U.P. Mainly distance of screen from first row ,gap btween seat rows,no.exhust fans,toilets,entery and exit gates etc as per the person capicity. —The preceding unsigned comment was added by Rajharshchauhan ( talk • contribs) 07:58, 22 April 2007 (UTC).
In chemistry the concentration of a species A is denoted by , but for chemical activity the square brackets should be replaced by curly brackets - {A}. How can the square brackets in math expressions such as the one below be replaced by curly brackets, given that curly brackets have a special significance in the math system?
Petergans 12:15, 22 April 2007 (UTC)
Meta probably describes it somewhere: meta:Help:Displaying a formula. The Wikipedia:Help desk might have some other tips. -- HappyCamper 13:46, 22 April 2007 (UTC)
If I connect a DC power source to an AC transformer, what happens?-- 172.131.238.148 12:38, 22 April 2007 (UTC)
I know this is a huge question, but I'm just looking for a ballpark figure. I'm not talking about frozen meat or meat in pre-packaged food (although I'm curious about those as well) -- I'm just looking for any information about how long ago the meat from the packaged meat counter was slaughtered. Anyone know? Days, weeks... months? Thanks in advance! - Quasipalm 16:17, 22 April 2007 (UTC)
This is one of the symptoms of some kidney problem (I don't remember the finer details) that a family member's cat has been diagnosed with. Am I correct in thinking that the cat will be in agony every time he urinates (AFAIK, uric acid forms a very sharp crystalline structure)? He apparently holds on for almost a day between pisses - which would make sense if this were the case... -- Kurt Shaped Box 16:17, 22 April 2007 (UTC)
I would like to know if there are any materials that are uv sensite (not light sensetive). A material that, when exposed to a certain amount of uv light, will react in some way. It can either be to change color or to change shape, form or size.
Thank You 17:29, 22 April 2007 (UTC)~ Tertius F.
Hi
I'm a noob so that's why im doing it like this.
The thing is, the uv sensitive material I'm refering to should be something in the line of AgCl or something like that. I know AgCl is used in photo's, not that Im looking for the same reaction(coping of an image, rather the color change properties). The project Im working on needs at least one example of a substance that will change color after a certain amount of time in the sun (uv rays). Maybe some sort of silver halide that one can put in paint that darkens after a certain amouth of exposure to uv rays?
The problem is, it should react to the uv rays but not the light.
Or... Is there an invention that can measure uv rays like the radion patches that people wear who work in nuclear facilities. Something that detects uv rays and can give an indication according to how much rays it has absorbed?
Thanx again T.F —The preceding unsigned comment was added by 196.207.47.60 ( talk) 18:54, 22 April 2007 (UTC).
What I mean is, that it should react to UVA or UVB rays. The other possibility is if the material in question were to be able to react to light in the same amount of time that it absorbes uv rays. sort of like Time/Light = Time/UV rays. (some strange formula, i know)
The problem is, that lets say its paint on a wall, one day it will take the wall 3h to change color, and other days it will take 6h, just as long as its able to indicate that the paint has absorbed a certain amount of uv rays.
Thanx it help a lot. Not exactly what I had in mind but I can see it working in my project. You have been a great help.
Cheers T.F
There was a strange insect fluttering round my room the other night, and I have no idea what it was. I got a photo of it when it was sitting beside my laptop - for the purposes of scale, the green thing is the plug on my mouse, and it's about 1 1/4 inches long. It didn't buzz at all (just clattered a bit against the wall as it flew), and didn't seem distressed by my being there. I've googled phrases like "picture guide to insects" and had a flick through the article Insect (and related articles too), but can't find anything helpful - does anyone know what this thing is? I'm in southern England at the moment, if that's any help. -- ZsigE 20:05, 22 April 2007 (UTC)
Can you tell me if there are any contraindications or interactions from/with other meds. or herbs? I have looked on many cites including wikipedia. I can't find any thing concerning interactions or contraindications. Thank you curlyhorse
(as a start, the usual spelling is "Gymnema sylvestre") I would call your physician's attention to [2] "DrugDigest is the consumer health and drug information website of Express Scripts, Inc. (ESI), the nation's largest independent pharmacy benefit manager (PBM). Through its corporate relationships, ESI designs and manages prescription drug plans.... The goal of DrugDigest is to provide ESI members and the public with the information they need to lead healthier lives. " it's a professionally responsible source that includes scientific references. I consider it appropriate for librarians to give references to sources of reliable information, though not to provide medical advice. DGG 03:40, 23 April 2007 (UTC)
title- nuclear physics question-explain what would happen in a nuclear reactor if the coolant fluid leaked out of the core? —The preceding unsigned comment was added by 82.29.69.23 ( talk) 20:50, 22 April 2007 (UTC).
I'm assuming you mean primary coolant. In my understanding, nuclear reactors emit neutrons that are either "fast" or "slow". In some designs, the coolant is the moderator and turns the useless fast neutrons into slow ones. Therefore, if the primary coolant is removed, there are not enough slow neutrons to sustain the reaction and the core cools. Loss of secondary coolant may result in problems however. In other designs, the coolant is not the moderator and loss of coolant and moderator results in thermal runaway. -- Tbeatty 04:03, 23 April 2007 (UTC)
I asked this question on the humanities desk and it was suggested I ask it here also.
Ok, so we base out mathematics on axioms, things we accept without proof (such as one plus one equals two). If we accept something without proof, it is a philosophy. So wouldn't that make all of math a philosophy? That would be alright, it is just that we use math as the language of science. So wouldn't that make all our science equations written in math just a philosophy? Just our interpretation of the universe? I suppose this would supported by the fact that quantum mechanics has many different interpretations, and you can even take classes on the philosophy of quantum mechanics [3]. Isn't this kind of a big deal that all of our science may not be leading us to the reality, but only one interpretation of it? Imaninjapirate talk to me 22:06, 22 April 2007 (UTC)
You are asking about a lot of things. Basically you are asking:
First of all, there is no such thing as a singular Mathematics. Mathematics consists of a collection of diverse mathematical concepts. Some of the mathematical concepts are independent of other mathematical concepts.
Second, mathematical concepts are just like a game. It has rules. The rules are made up by humans. New mathematical concepts are made up all the time.
However, not all mathematical concepts survive into the future. Countless mathematical concepts have been abandon by mathematicians. You do not read or come across these abandon mathematical concepts because they are NOT taught in school.
Instead what you are taught in school/university are those mathematical concepts that have survived the passage of time. Thus these concepts worked and are useful in real life. In short there is evolution in mathematical concepts, they are subjected to natural selection by mathematicians.
That's why maths "works" in real life. Because those mathematical concepts that "did not work" has not survived.
202.168.50.40 01:45, 23 April 2007 (UTC)
The difference between philosophy and science is its testability. All scientific hypothesis is testable by definition, including 1+1=2. Philosophy is not defined by it's testability. Theories of God, goodness, utility, etc, are all fundamentally untestable. When philosophy is testable it becomes science, and when science becomes untestable it is philosophy. -- Tbeatty 02:50, 23 April 2007 (UTC)
Well, aren't those things at least partially testable? I mean this in the sense of narrowing down the answers in a multiple-choice problem:
"What is [indiscernible number]+[indiscernible number]?"
a. £ b. cheese c. 4 d. 6
To say that something is discretely "testable" or "untestable" is mistaken. There are degrees of certainty, and in my example problem, it is quite clear that a and b are NOT the correct answers. This can be tested (albeit non-physically) with the following sort of logic:
So the difference between science and philosophy is the method of testing. Philosophical notions, just like scientific theories, are used to explain. But the key here is the testing itself. Philosophy uses pure logic to test its notions, while science uses experimentation. Something like, for instance, a proof of God, can be shown to be false. This is what happened with the Ontological argument. The consensus of contemporary philosophers is that the argument is fallacious. The only difference is that there is much less to test. I personally see nothing different between using a Modus ponens to prove something, or to measure it in a laboratory.-- Kirby♥ time 10:36, 24 April 2007 (UTC)
I was wondering if it is possible to rip a shark's gills with your hands, what do ya think? Bastard Soap 22:07, 22 April 2007 (UTC)