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Frst Grade Rocks! Ω
Always a student, rarely a master. Some you can learn from, some you can teach, some you can laugh with. ╔╗╔═╦╗ ║╚╣║║╚╗ ╚═╩═╩═╝ ******** Useful Math Symbols http://tlt.its.psu.edu/suggestions/international/bylanguage/mathchart.html#common √ ∛ ∫ ∮ ⋀ ⋁ ∇▿ Δ ▵ ƒ ∂ ∑∏∈∀∃ ∴ ∠ ∡ x ⁰ ¹ ² ³ ⁴ ֿ¹ ֿ² ֿ³ ֿ ⁺ ⁻ ª ⁿ ʹ ʺ ‴ ° ˅ ˆ ˜ ₐ ᵢ ₒ ₓ ₀ ₁ ₂ ⁄ ← → ⇒ ≅ ≡ ≈ ≠ ∝∼ ≤ ≥ ± 3 ⁄4 3∕4 ÷ × − ∗ ⋅∙ ½ ⅓ ⅔ ¼ ¾ ⅛ ⅜ ⅝ ⅞ ∞ ℏ Α Β Γ Δ Ε Ζ Η Θ Ι Κ Λ Μ Ν Ξ Ο Π Ρ Σ Τ Υ Φ Χ Ψ Ω α β γ δ ε ζ η θ ι κ λ μ ν ξ ο π ρ σς τ υ φ χ ψ ω ☺ I leave censorship to the Socialites Put a pot of water on a burner and the water will understand that it has to boil. Entropy knows it must increase in order to balance out the system
Why is Fox news now calling Osama bin Laden "USAma" bin Laden?
I noticed them doing it yesterday on their scroll at the page bottom and they were at it again today. Strange, bemusing, ironic. Guess they collectively went off their meds.
I added the all caps "USA" for clarity, but I see "USA" every time they post OBL's new name.
22 réponsesPoliticsil y a 1 décennieWhat is the difference, if any, between Integrity and Scientific Integrity?
This is a follow up to Koshka's question on climate-gate: http://answers.yahoo.com/question/index;_ylt=AiO1u...
4 réponsesGlobal Warmingil y a 1 décennieDoes groundhog day have any astronomical meaning?
Groundhog day is February 2nd and is a minor celebration in the USA. Supposedly, if a groundhog comes out of its burrow and sees its shadow, we will have 6 more weeks of winter.
12 réponsesAstronomy & Spaceil y a 1 décenniePeriod of pendulum in a relativistic train moving on a flat earth?
A train travels at 6/10 c on a flat earth with a uniform gravitational field of g. (For flat earth, see: http://answers.yahoo.com/question/index;_ylt=AhI7T... )
The train has a pendulum where the length of the (massless) cord holding the bob is 1 meter.
What is the period of the pendulum as measured on the earth and on the train?
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This is based on an old Alexander problem archived someplace in Y!A
2 réponsesPhysicsil y a 1 décennieEarly sunrise in Greenland. Is the explanation of scientist attributing it to global warming wrong?
Ilulissat is Greenland's westernmost outpost and it is above the arctic circle (69° N). This year sunrise occurred on January 11, two days ahead of normal.
http://www.dailymail.co.uk/sciencetech/article-134...
One of the scientist who was interviewed for the article said that "by far the most obvious explanation the early sunrise" was the melting icecap which lowered the optical horizon.
I have a strong suspicion that answer is wrong.
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To solve this, you should google earth Ilulissat, Greenland.
You might also need to know something about physics and topography. It would also helps to know a little bit about the arctic and sea ice, but that is not necessary.
An additional hint, is that the first rays of the sun would not necessarily be observed from the center of town since it has small hills to the south.
14 réponsesGlobal Warmingil y a 1 décennieAre we in pergatory and the skeptics are going to freeze and the believers roast?
It sure seems that is the way everyone is argues in this section.
Fire and Ice
Some say the world will end in fire,
Some say in ice.
From what I've tasted of desire
I hold with those who favor fire.
But if it had to perish twice,
I think I know enough of hate
To say that for destruction ice
Is also great
And would suffice.
Robert Frost
3 réponsesGlobal Warmingil y a 1 décennieHow much heat was generated in the formation of the earth?
I'm looking for the amount of heat generated by the gravitational collapse. You can assume the earth is constant density.
Bonus question: What would you estimate the average temperature to be after the collapse?
7 réponsesPhysicsil y a 1 décennieGravity on a flat earth?
Imagine a flat earth extending to infinity in all directions. How thick would the earth need to be to have the same gravity at the surface as we have now.
Assume a density of 5,515 kg/m³
g = 9.81 m/s²
3 réponsesPhysicsil y a 1 décennieSkeptics, how are "warmies" deluded?
I will pick the best answer from the skeptics camp (i.e., Trevor, et al., you are welcome to answer, but you will not get best answer). It should be cogent, logical and not rely on anecdotal or irrelevant evidence.
As an aside, Y!A's first choice for suggested category was "Science & Mathematics > Alternative > Paranormal Phenomena" lmao.
Thank you.
14 réponsesGlobal Warmingil y a 1 décennieCarpooling question_?
You have a casual carpool where you have a varying number of people show up every day. How do you devise a system so that everyone in the pool deems it fair on who drives on a particular day
4 réponsesMathematicsil y a 1 décennieIs AGW really a problem?
Apart from:
1. CO2 acidification of the ocean,
2. Low risk, large consequences of releasing the stored carbon in the arctic and the sea floor and baking the earth.
I mean even if sea level rose at 4m per century, you could walk away. Sure we would lose some investments and some landmarks, but the economic payback of most investments is 7 to 20 years. So the economic cost of moving and setting up shop some place new is small over the long run (over a period of a century).
And the argument that we will lose species because they are isolated and can't move is not really the fault of AGW, but of mankind's development and exploitation of nature along with habitat destruction
Anything that I'm missing?
7 réponsesGlobal Warmingil y a 1 décennieShouldn't we just repeal Beer's law, Kirchhoff's law, Planck's law and the law of exponential decay?
New Republican congress. Global warming is history. Yahoo!
6 réponsesGlobal Warmingil y a 1 décennieWhat are the answers to this series?
√[ 1 - √( 17/16 - √[ 1 - √( 17/16 - √[ 1 - √( 17/16 - √[ 1 -√( 17/16 ... ) ] ) ] ) ] ) ]
There is a real (which I have solved) and there might be a complex solution
5 réponsesMathematicsil y a 1 décennieWhy do I have to heat the house to a warmer temperature on cold days to feel the same?
----> I asked this question in Physics 2 days ago and I don't feel I got a good answer. http://answers.yahoo.com/question/index;_ylt=Atmu_... Since this question uses a lot of the tools necessary to understand global warming, I thought I'd ask here. This is not a political question so it does not depend on your favorite flavor of kool-aid. <---
I have a small house. It is poorly insulated (no wall insulation and some air leaks). It also has a large amount of windows and side walls per square foot. And I have a cement slab floor.
Normally, I can wander around the house comfortably in shorts if the inside air temperature is 60° F. But it is record cold outside today. Got down to the high 30s outside last night.
So I set the heater at 60° F. And it is cold. I have two sweatshirts on and my jeans and feet feel cold.
The inside air temperature is correct. What is going on?
True to life story, only mildly exaggerated.
**********Additional Details **********
It is a rental. lol. And it is not a question about how to mitigate heat loss.
What I am actually asking is to why the air temperature differs from the temperature I feel.
7 réponsesGlobal Warmingil y a 1 décennieWhy do I have to heat the house to a warmer temperature on cold days to feel the same?
I have a small house. It is poorly insulated (no wall insulation and some air leaks). It also has a large amount of windows and side walls per square foot. And I have a cement slab floor.
Normally, I can wander around the house comfortably in shorts if the inside air temperature is 60° F. But it is record cold outside today. Got down to the high 30s outside last night.
So I set the heater at 60° F. And it is cold. I have two sweatshirts on and my jeans and feet feel cold.
The inside air temperature is correct. What is going on?
True to life story, only mildly exaggerated. Best physics answer.
5 réponsesPhysicsil y a 1 décennieCan anyone show that the period for dropping a rock through a hole in the earth is just like low earth orbit?
Assuming that the earth is constant density and a hole is drilled through the earth from the south pole to the north pole, and a rock is dropped into the hole and eventually pops back up after a period of time. Show that the period of the rock is the same as the period of a rock launched into low earth orbit.
Assume the only force acting on either rock is gravity. i.e., no friction, air resistance, or other non-conservative force.
Third grade is so hard. It makes my head hurt.
3 réponsesPhysicsil y a 1 décennieWhy are mountain shadows always triangles?
I mean big mountain near daybreak or sunset. If you don't believe me, here are some pictures:
http://i125.photobucket.com/albums/p53/mkvispics/M...
http://epod.usra.edu/blog/2007/12/mountain-shadow-...
http://www.alpinestateofmind.com/gallery/6496951_G...
http://www.exo.net/~pauld/lectures/patternscostari... (scroll down a little)
4 réponsesPhysicsil y a 1 décennieHow can lasers both cool atoms to near zero yet power fusion reactors?
Laser have cooled atoms to the lowest temperature know in the universe and can power nuclear fusion reactors.
There should be a law (black body, thermo, et al) against that type of stuff, right?
5 réponsesPhysicsil y a 1 décennieIs the proton beam in the LHC hot or cold?
5 réponsesPhysicsil y a 1 décennieHow can a wind powered vehicle go downwind faster than the wind?
Here is a video of a vehicle that is wind powered and can go downwind over twice as fast as the wind.
http://www.youtube.com/watch?v=5CcgmpBGSCI&feature...
Best explanation.
You need to analyze how it works at below the speed of the wind, how it transitions from slower than wind speed to faster than wind speed and how it travels faster than the wind.
This is a gedanken experiment. Prefer independent thought over looking something up.
8 réponsesPhysicsil y a 1 décennie