Science & Mathematics - 20 October 2006

how can we prove that the earth is actually like any other planet and not the centre of the universe, and the whole universe is actually moving around it?

2006-10-20 15:10:07 · 14 answers · asked by Anonymous in Astronomy & Space

I've seen quite a few people putting some mathematical symbols and Greek letters in both their questions and answers here on Yahoo Answers. I've been trying to find a way to do it. I just found one that will allow some to be entered. I go into MS Word; click on "Insert" in the tool bar at the top. Then, on the drop-down menu that results, click on "Symbol". This gives you a choice of lots of symbols and non-Roman letters like Greek, Hebrew, Arabic, etc. So you insert those into an empty MS Word doc and then cut-and-paste them into the Answers question (or details) entry window. Here are examples: Ψ, φ, θ, λ, ∑, ∏, ∞, √, ∫, ∂, ∆.

Do you know of any other ways to do this? I'm especially interested in ways that will allow more symbols.

2006-10-20 15:09:32 · 4 answers · asked by pollux 4 in Mathematics

I understand that visually the object does not appear to have moved. However, there are a few things that make me question that point.

1. Position is measured by how many radians from the reference point the object is. After a rotation it is reasonable to say it is 2pi from the reference point, and not zero. (i think) If this is the case then displacement equals theta2 - theta 1 = 2pi. Directions are measured clockwise and counter clockwise as opposed to absolute distance from the reference point.

2. work = force x displacement. I understand that this is for linear motion but I think it is safe to say the angular version has a similiar relationship. If rotating 2pi = 0 displacement then rotating a wheel one cycle would result in no work done, which is not the case because the wheel is now spinning with angular velocity.

Is position 2pi = to 0? It does not make any sense if it does. If it actually does please provide a good explanation please. I don't want a meaning less answer.

2006-10-20 15:08:11 · 6 answers · asked by alex m 1 in Physics

You can also give me problems or activites involving free fall.

2006-10-20 15:03:48 · 2 answers · asked by junior 1 in Physics

Technology could never allow man to travel to the moon in the 1960's. If they did it was luck only.. I seriously believe it was all a load of studio based, foothold rubish in the days of the cold war. - no man has walked on the moon !!

2006-10-20 14:59:56 · 36 answers · asked by Anonymous in Other - Science

2006-10-20 14:56:19 · 1 answers · asked by summer_510 2 in Engineering

When you are in a car going at 70 miles per hour, and you throw a stone forwards out of the window, it briefly benefits from the relative velocity of the car, and therefore travels much further than the speed it would normally travel at after being thrown. Scientists say that if you were going the speed of light in a car, then turned the lights on, you would not see them, as you would be travelling as fast as the light, and therefore it would not have time to travel forward so you could see it.

Why does the same principal as the stone benefiting from the velocity of the car not apply? Surely the light would still be visible, as it would be travelling away from the car at (speed of light) + (speed of light)?

2006-10-20 14:54:09 · 10 answers · asked by Nick E 2 in Mathematics

2006-10-20 14:49:24 · 15 answers · asked by blubirdbye 1 in Weather

2006-10-20 14:47:26 · 19 answers · asked by atec12 1 in Other - Science

2006-10-20 14:46:36 · 21 answers · asked by Anonymous in Biology

2006-10-20 14:44:46 · 3 answers · asked by reaful 2 in Weather

2006-10-20 14:44:12 · 3 answers · asked by Anonymous in Other - Science

What is the calculus behind the commutative relationship of angular momentum [LxLy] = i(hbar)Lz where

Lx = -i(hbar)(yd/dz - zd/dy)
Ly = -i(hbar)(yd/dz - zd/dy)
Lz = -i(hbar)(xd/dy - yd/dx)

2006-10-20 14:42:13 · 2 answers · asked by nathaniel49 2 in Mathematics

American and British researchers have made a cloak of invisibility-if you've read ( I'm sure you're already familiar with the name ) Harry Potter, you'll know what this means. What do you think? Plausible or not? Before you click the button that says answer question, please read the article and then make your point and why. We already know that parallel universes exist- so why not this? My inquiring mind wants to know what you think.Thanks for your time.
http://msnbc.msn.com/id/15329396/ to read more on the article.

2006-10-20 14:39:51 · 12 answers · asked by ? 7 in Physics

2006-10-20 14:39:42 · 10 answers · asked by Jimbo 1 in Mathematics

2006-10-20 14:32:29 · 18 answers · asked by Anonymous in Zoology

I ride a motorcycle and it gets rather chilly when riding. I'm not interested in all the elaborate details, but please give me a simple rule of thumb to determine wind chill. For example 1/2 degree for every mile per hour, or something similar. I just want a decent approximation

2006-10-20 14:29:45 · 4 answers · asked by Billy 4 in Weather

If the weatherman says there is a 50% chance of rain and it does not rain, was he right or wrong? Don't you wish YOU could get a job like that?

2006-10-20 14:26:56 · 14 answers · asked by Picture Taker 7 in Earth Sciences & Geology

-Did you know that 0^1 is greater than 0^0?
-Did you know there are more points in a circumference radius 2 than in a circumference with radius 1?
-Did you know that in Geometry is TRUE that ((a triangle is not a square) AND (a square is not a rectangle))?
-Did you know that (infinity + 1) is greater than just (infinity)?

2006-10-20 14:23:18 · 9 answers · asked by f_vidigal 1 in Engineering

2006-10-20 14:20:28 · 4 answers · asked by raju patel 1 in Engineering

?? I am trying to enter a contest, but I am trying to think of something smart. Things that follow laws, like "equal and opposite reaction" where some guy is bumping into two other guys.. stuff like that. what should i do?

2006-10-20 14:07:47 · 10 answers · asked by Anonymous in Physics

2006-10-20 14:07:19 · 8 answers · asked by Adam 1 in Mathematics

2006-10-20 14:04:57 · 6 answers · asked by eunjin098 1 in Biology

need help with this problem:
what is the inverse of y= (pie)/2 + cos-1x

cos-1 also means arccos

thanks :)

2006-10-20 14:04:45 · 5 answers · asked by trish 2 in Mathematics

2006-10-20 14:04:28 · 3 answers · asked by abstemious_entity 4 in Biology

2006-10-20 14:03:54 · 8 answers · asked by nour 1 in Biology

The French Academy of Science proclaimed at in 1772 that meteorites were just superstitious nonsense, because rocks could not fall from the sky. But, did museums really throw out their specimens? Is it hard to find meteorite specimens in Europe that date prior to 1790? Anyone know this? Thanks, I am writing a book on the history of science.

2006-10-20 14:01:55 · 4 answers · asked by Crazy Eagle 3 in Astronomy & Space

3 + Square root x^ 2 -8x = 0

It looks like squaring the x^2-8x=0
add 3

2006-10-20 14:00:54 · 4 answers · asked by Anonymous in Mathematics

Hard time understanding how to do the SqRt with fractions

Sqrt 6 / Sqrt 7 * Sqrt 14 / Sqrt 3

Do I just square them, and use the regular
multiplication fo the fraction, or is thre something else I am
supposed to do?

2006-10-20 13:58:46 · 5 answers · asked by Anonymous in Mathematics

My algrbrator will do square roots, but I am having a hard time putting in the information where it actually looks correct.

Square root 2t^5 * Square root 10^4

and

(3 - 2 Square root 7)(3 + 2Square root 7)

I have a whole bunch to try to solve, and if I can get the idea, I think I can finish all the other ones myself.. can someone help?

2006-10-20 13:53:30 · 5 answers · asked by Anonymous in Mathematics