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I'm sure it's a pretty common species, and we probably already have zillions of photos of it on Commons... but still... what kind of spider is it?
Photo was taken in Indianapolis, Indiana in July of last year. ~ ONUnicorn( Talk| Contribs) problem solving 02:29, 15 May 2008 (UTC)
That appears to be a grass spider, genus
Agelenopsis (all I did was look up "common spiders" and found it pretty quickly...)
--
DrVornado (
talk) 02:34, 15 May 2008 (UTC)
Thanks. It does look like the spiders on that page... though the web it was on sure seemed sticky (see all the stuff stuck to it in the picture?) :) ~ ONUnicorn( Talk| Contribs) problem solving 12:37, 15 May 2008 (UTC)
1. Like to know the names of atleast 5 inventors who died testing their invention 2.Kindly provide a brief detail about the invention and how the person died
Thanks 118.92.106.168 ( talk) 06:17, 15 May 2008 (UTC)
London is sinking by 1-2 mm per year due to sea-level rise. If London is sinking by 1-2 mm per year, then a calculation can be made that by 2100, London will sink 100 mm and by 2200, it will sink upto 200 mm. My question is that if a city like London sinks 200 mm, then what will the effect? Will it become inhabitable? Otolemur crassicaudatus ( talk) 09:02, 15 May 2008 (UTC)
Just to clarify, but if I'm reading the introduction to the article correctly, the "sinking" is not due to sea level rise, but combining with it to produce a "double whammy". That is, any sea level rise is a separate issue from the landmass sinking. I didn't have time to read the article, but shouldn't the islands still be rising from post-glacial rebound? Matt Deres ( talk) 18:31, 15 May 2008 (UTC)
London isn't too bad off compared to other parts of the North Sea. Dragons flight ( talk) 18:56, 15 May 2008 (UTC)
With reference to the Wikipedia article on Cold Cathode:
http://en.wikipedia.org/wiki/Cold_cathode
I should be very grateful if either a contributer to the article or a user knowledgeable about the construction and technology of CCFLs used as LCD backlights in televisions and computer monitors could clarify whether these CCFLs actually do contain a radioactive material that emits beta particles to start the ionization of the gas. If this is the case, then would it be correct to assume that facing the back of the computer monitor where the backlight can be seen shining through the grill that one is being exposed to ionizing radiation - since the fast moving beta particles would penetrate the thin glass of the backlight? 78.147.162.37 ( talk) 12:13, 15 May 2008 (UTC)
Julia Howard —Preceding unsigned comment added by 78.147.162.37 ( talk) 12:01, 15 May 2008 (UTC)
When we move on a wooden floor with heel shoe why marks or scratches are left on the floor? —Preceding unsigned comment added by MAQMAQ ( talk • contribs) 12:08, 15 May 2008 (UTC)
Hi all,
Let's say I charge a capacitor. The capacitor now has one plate with more negative charges than positive, and one plate with more positive charges than negative. If I then touch one of the plates to a hunk of metal, will I discharge half the capacitor? I'm guessing yes, because the charges between the plate and the metal will balance out, and since the tiny capacitor won't make much of an effect on the hunk of metal, both the plate and the metal will end up with (almost) no net charge. Is that right?
Second question: What will happen if I touch the negative side of a battery to a hunk of metal? Anything at all? Thanks!
Do mice eat candle wax because it is good for them or because there is nothing else and they are hungry? Because my bro said the mice in his house were eating the candle wax from his candles. What nutritional benefit would a mouse get from eating the candle wax from a candle? Terror toad ( talk) 13:13, 15 May 2008 (UTC)
What is the formula for the spectral lines of helium? Em3ryguy ( talk) 14:16, 15 May 2008 (UTC)
I know in metric/SI units that Joules referes to mechanical work and newton meters refers to torque, even though they're bot N x m. But foot pounds are a little more ambigious. Is it acceptable to use foot pounds interchagably between mechanical work and torque? Thanks Deltacom1515 ( talk) 16:14, 15 May 2008 (UTC)
No idea why that's not formatted correctly. Deltacom1515 ( talk) 16:14, 15 May 2008 (UTC)
Wow, way to read. I completly missed that. Guess that answered my question. Deltacom1515 ( talk) 16:33, 15 May 2008 (UTC)
It is said that the area of the cathode in an MFC helps improve the efficiency of the MFC. Is this true? Why is it so? —Preceding unsigned comment added by 59.92.47.158 ( talk) 16:39, 15 May 2008 (UTC)
note: question moved from Wikipedia talk:WikiProject Physics
I was wondering, since it's possible to accelerate particles to near the speed of light, is it possible to decelerate particles, and if so, how? (nb. I failed physics, so I wouldn't know myself) Avnas Ishtaroth ( talk) 12:49, 15 May 2008 (UTC)
Hi. Today when I hid the sun behind an object that just obscures the sun's disk, I saw what looked like a heavy snowstorm, only it was May, and the sky was a clear blue with only a few fractus clouds in the distance. Anyway, and this is not homework, I speculated that they were dandelion seeds, which was confirmed when I saw them close up. However, around the sun, several hundred seed packets could be seen, ranging from probably 1 - 50 metres above ground. The wind was strong and from the north, I live in southern Ontario. Anyway, there must have been one per every cubic metre or two, as the highest ones near the sun were maybe as small as 10 arcmins apart from each other. Where did they all come from? To my north there are about 20 hectares of land capable of producing seeding dandelions. This means there must have been over a million individual seeding dandelions producing seed packets! In early to late June, there may be as many as 500 dandelions per square metre in some places, I estimate, if they haven't been mowed yet. Are they an invasive species in North America? If the climate warms a few degrees, warm conditions become longer throught the year, and rainfall becomes sporadic but interspresed with heavy and brief downpours, will there be more invasive dandelions? If so, what will happen to the local ecosystems? Also, do flowering dandelions close and reopen to become seeding ones, and how long does this take? A look at any random part of the sky or landscape for a few seconds will reveal at least a few of these seed packets, and sometimes several dozen! Do people consider them weeds because they're an invasive species or because they choke other vegetation? Thanks. ~ A H 1( T C U) 17:34, 15 May 2008 (UTC)
The other day I saw an interesting episode of The Universe which discussed the end of the universe through heat death, with the final dark age of the cosmos being one in which all black holes have finally evaporated and all that is left are stray random photons.
This got me wondering, though. Since light is a form of energy, and general relativity says that energy as well as matter bends space/time, does it follow that light can attract itself through gravitational force? After all, if a photon of light contains energy than it should, I think, very slightly bend space/time and thus attract energy and matter. Would it follow that two beams of light fired initially in parallel would slightly bend toward each other even in the absence of other energy or matter? And if so, would it be possible that in the universe's final dark age that stray photons could very, very slowly bend towards each other into wide orbits, producing large galactic size pockets of slightly higher than normal electromagnetic energy or heat? Dugwiki ( talk) 17:41, 15 May 2008 (UTC)
I am looking for examples of situations where there is a need to keep solid particles suspended in water. One example I know of is oil drilling - as the drill progresses the little bits of broken rock need to be carried away in a stream of water - certain additives are added to the water to help keep the rock bits in suspension. Can you think of any other situations? I am more interested in industrial or agricultural applications, less in medical or food applications. Thanks! ike9898 ( talk) 17:42, 15 May 2008 (UTC)
how much methane and CO2 do 6 billion people breate out or fart out each day? Paul kahlich ( talk) 17:49, 15 May 2008 (UTC)
I'm looking for the density of paraffin wax in liquid phase. The wax we're using melts at 85°C (used in a car thermostat just in case you're wondering) but I'm not familiar with any good sites or databanks? Thanks in advance —Preceding unsigned comment added by 193.190.253.149 ( talk) 18:58, 15 May 2008 (UTC)
What are the relative strengths of lamp posts and trees (say, of equal width?) when struck, such as by a speeding car? Has there been experiments done on this?-- Fangz ( talk) 19:30, 15 May 2008 (UTC)
1. Is it possible for the brain/nervous system to run out of transmitter chemicals? 2. If so, how and from what is the supply replenished? 3. If neurotransmitters are re-used, where are they stored when not in use? —Preceding unsigned comment added by 69.224.182.55 ( talk) 20:37, 15 May 2008 (UTC)
Why don't you ever see Squirrel feces on the ground? You see Bird / duck feces, but never other large animals like raccoons. LLOTAAMI ( talk) 20:56, 15 May 2008 (UTC)
Hi, my name is Lindsay, a fifth grade student. I need help with this topic: LIST WATER'S FREEZING POINT AND MELTING POINT IN BOTH DEGREES, CELSIUS AND FAHRENHEIT.I really need help on it and I couldn't find any imformation on it. I'm still doing my rough draft that is due May 20,2008.PLEASE HELP ME!!!! —Preceding unsigned comment added by 71.243.52.218 ( talk) 21:56, 15 May 2008 (UTC)
Are benzene and other aromatic compounds are often represented as a resonance of 2 structures with double bonds. Is benzene really a superposition of 2 cyclohexatrienes, i. e. if you somehow detect an electron between carbon 1 and carbon 2 and then do a measurement (very quickly after the first measurement) is there a higher chance of finding an electron between carbon 3 and carbon 4 or carbon 5 and carbon 6 than in the other gaps between the carbon atoms? Thanks. 201.66.22.129 ( talk) 22:31, 15 May 2008 (UTC)
Science desk | ||
---|---|---|
< May 14 | << Apr | May | Jun >> | May 16 > |
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. |
I'm sure it's a pretty common species, and we probably already have zillions of photos of it on Commons... but still... what kind of spider is it?
Photo was taken in Indianapolis, Indiana in July of last year. ~ ONUnicorn( Talk| Contribs) problem solving 02:29, 15 May 2008 (UTC)
That appears to be a grass spider, genus
Agelenopsis (all I did was look up "common spiders" and found it pretty quickly...)
--
DrVornado (
talk) 02:34, 15 May 2008 (UTC)
Thanks. It does look like the spiders on that page... though the web it was on sure seemed sticky (see all the stuff stuck to it in the picture?) :) ~ ONUnicorn( Talk| Contribs) problem solving 12:37, 15 May 2008 (UTC)
1. Like to know the names of atleast 5 inventors who died testing their invention 2.Kindly provide a brief detail about the invention and how the person died
Thanks 118.92.106.168 ( talk) 06:17, 15 May 2008 (UTC)
London is sinking by 1-2 mm per year due to sea-level rise. If London is sinking by 1-2 mm per year, then a calculation can be made that by 2100, London will sink 100 mm and by 2200, it will sink upto 200 mm. My question is that if a city like London sinks 200 mm, then what will the effect? Will it become inhabitable? Otolemur crassicaudatus ( talk) 09:02, 15 May 2008 (UTC)
Just to clarify, but if I'm reading the introduction to the article correctly, the "sinking" is not due to sea level rise, but combining with it to produce a "double whammy". That is, any sea level rise is a separate issue from the landmass sinking. I didn't have time to read the article, but shouldn't the islands still be rising from post-glacial rebound? Matt Deres ( talk) 18:31, 15 May 2008 (UTC)
London isn't too bad off compared to other parts of the North Sea. Dragons flight ( talk) 18:56, 15 May 2008 (UTC)
With reference to the Wikipedia article on Cold Cathode:
http://en.wikipedia.org/wiki/Cold_cathode
I should be very grateful if either a contributer to the article or a user knowledgeable about the construction and technology of CCFLs used as LCD backlights in televisions and computer monitors could clarify whether these CCFLs actually do contain a radioactive material that emits beta particles to start the ionization of the gas. If this is the case, then would it be correct to assume that facing the back of the computer monitor where the backlight can be seen shining through the grill that one is being exposed to ionizing radiation - since the fast moving beta particles would penetrate the thin glass of the backlight? 78.147.162.37 ( talk) 12:13, 15 May 2008 (UTC)
Julia Howard —Preceding unsigned comment added by 78.147.162.37 ( talk) 12:01, 15 May 2008 (UTC)
When we move on a wooden floor with heel shoe why marks or scratches are left on the floor? —Preceding unsigned comment added by MAQMAQ ( talk • contribs) 12:08, 15 May 2008 (UTC)
Hi all,
Let's say I charge a capacitor. The capacitor now has one plate with more negative charges than positive, and one plate with more positive charges than negative. If I then touch one of the plates to a hunk of metal, will I discharge half the capacitor? I'm guessing yes, because the charges between the plate and the metal will balance out, and since the tiny capacitor won't make much of an effect on the hunk of metal, both the plate and the metal will end up with (almost) no net charge. Is that right?
Second question: What will happen if I touch the negative side of a battery to a hunk of metal? Anything at all? Thanks!
Do mice eat candle wax because it is good for them or because there is nothing else and they are hungry? Because my bro said the mice in his house were eating the candle wax from his candles. What nutritional benefit would a mouse get from eating the candle wax from a candle? Terror toad ( talk) 13:13, 15 May 2008 (UTC)
What is the formula for the spectral lines of helium? Em3ryguy ( talk) 14:16, 15 May 2008 (UTC)
I know in metric/SI units that Joules referes to mechanical work and newton meters refers to torque, even though they're bot N x m. But foot pounds are a little more ambigious. Is it acceptable to use foot pounds interchagably between mechanical work and torque? Thanks Deltacom1515 ( talk) 16:14, 15 May 2008 (UTC)
No idea why that's not formatted correctly. Deltacom1515 ( talk) 16:14, 15 May 2008 (UTC)
Wow, way to read. I completly missed that. Guess that answered my question. Deltacom1515 ( talk) 16:33, 15 May 2008 (UTC)
It is said that the area of the cathode in an MFC helps improve the efficiency of the MFC. Is this true? Why is it so? —Preceding unsigned comment added by 59.92.47.158 ( talk) 16:39, 15 May 2008 (UTC)
note: question moved from Wikipedia talk:WikiProject Physics
I was wondering, since it's possible to accelerate particles to near the speed of light, is it possible to decelerate particles, and if so, how? (nb. I failed physics, so I wouldn't know myself) Avnas Ishtaroth ( talk) 12:49, 15 May 2008 (UTC)
Hi. Today when I hid the sun behind an object that just obscures the sun's disk, I saw what looked like a heavy snowstorm, only it was May, and the sky was a clear blue with only a few fractus clouds in the distance. Anyway, and this is not homework, I speculated that they were dandelion seeds, which was confirmed when I saw them close up. However, around the sun, several hundred seed packets could be seen, ranging from probably 1 - 50 metres above ground. The wind was strong and from the north, I live in southern Ontario. Anyway, there must have been one per every cubic metre or two, as the highest ones near the sun were maybe as small as 10 arcmins apart from each other. Where did they all come from? To my north there are about 20 hectares of land capable of producing seeding dandelions. This means there must have been over a million individual seeding dandelions producing seed packets! In early to late June, there may be as many as 500 dandelions per square metre in some places, I estimate, if they haven't been mowed yet. Are they an invasive species in North America? If the climate warms a few degrees, warm conditions become longer throught the year, and rainfall becomes sporadic but interspresed with heavy and brief downpours, will there be more invasive dandelions? If so, what will happen to the local ecosystems? Also, do flowering dandelions close and reopen to become seeding ones, and how long does this take? A look at any random part of the sky or landscape for a few seconds will reveal at least a few of these seed packets, and sometimes several dozen! Do people consider them weeds because they're an invasive species or because they choke other vegetation? Thanks. ~ A H 1( T C U) 17:34, 15 May 2008 (UTC)
The other day I saw an interesting episode of The Universe which discussed the end of the universe through heat death, with the final dark age of the cosmos being one in which all black holes have finally evaporated and all that is left are stray random photons.
This got me wondering, though. Since light is a form of energy, and general relativity says that energy as well as matter bends space/time, does it follow that light can attract itself through gravitational force? After all, if a photon of light contains energy than it should, I think, very slightly bend space/time and thus attract energy and matter. Would it follow that two beams of light fired initially in parallel would slightly bend toward each other even in the absence of other energy or matter? And if so, would it be possible that in the universe's final dark age that stray photons could very, very slowly bend towards each other into wide orbits, producing large galactic size pockets of slightly higher than normal electromagnetic energy or heat? Dugwiki ( talk) 17:41, 15 May 2008 (UTC)
I am looking for examples of situations where there is a need to keep solid particles suspended in water. One example I know of is oil drilling - as the drill progresses the little bits of broken rock need to be carried away in a stream of water - certain additives are added to the water to help keep the rock bits in suspension. Can you think of any other situations? I am more interested in industrial or agricultural applications, less in medical or food applications. Thanks! ike9898 ( talk) 17:42, 15 May 2008 (UTC)
how much methane and CO2 do 6 billion people breate out or fart out each day? Paul kahlich ( talk) 17:49, 15 May 2008 (UTC)
I'm looking for the density of paraffin wax in liquid phase. The wax we're using melts at 85°C (used in a car thermostat just in case you're wondering) but I'm not familiar with any good sites or databanks? Thanks in advance —Preceding unsigned comment added by 193.190.253.149 ( talk) 18:58, 15 May 2008 (UTC)
What are the relative strengths of lamp posts and trees (say, of equal width?) when struck, such as by a speeding car? Has there been experiments done on this?-- Fangz ( talk) 19:30, 15 May 2008 (UTC)
1. Is it possible for the brain/nervous system to run out of transmitter chemicals? 2. If so, how and from what is the supply replenished? 3. If neurotransmitters are re-used, where are they stored when not in use? —Preceding unsigned comment added by 69.224.182.55 ( talk) 20:37, 15 May 2008 (UTC)
Why don't you ever see Squirrel feces on the ground? You see Bird / duck feces, but never other large animals like raccoons. LLOTAAMI ( talk) 20:56, 15 May 2008 (UTC)
Hi, my name is Lindsay, a fifth grade student. I need help with this topic: LIST WATER'S FREEZING POINT AND MELTING POINT IN BOTH DEGREES, CELSIUS AND FAHRENHEIT.I really need help on it and I couldn't find any imformation on it. I'm still doing my rough draft that is due May 20,2008.PLEASE HELP ME!!!! —Preceding unsigned comment added by 71.243.52.218 ( talk) 21:56, 15 May 2008 (UTC)
Are benzene and other aromatic compounds are often represented as a resonance of 2 structures with double bonds. Is benzene really a superposition of 2 cyclohexatrienes, i. e. if you somehow detect an electron between carbon 1 and carbon 2 and then do a measurement (very quickly after the first measurement) is there a higher chance of finding an electron between carbon 3 and carbon 4 or carbon 5 and carbon 6 than in the other gaps between the carbon atoms? Thanks. 201.66.22.129 ( talk) 22:31, 15 May 2008 (UTC)