Science & Mathematics - 25 September 2007

Birds fly. The sun performs fusion. The earth's core performs fission. Why isn’t there a small particle or a large star skipping and jumping back and forth in time?

2007-09-25 19:16:54 · 9 answers · asked by Anonymous in Physics

i did

sin 6t/cos6t/sin 2t...


umm.. if im going in the right track... should it be (sin 6t)(sin 2t)/cos6t... or should it be...
sin6t/(cos 6t)(sin 2t)???

2007-09-25 19:15:59 · 4 answers · asked by Anonymous in Mathematics

2007-09-25 19:14:16 · 11 answers · asked by Eric S 1 in Geography

A generator is made from 100 turn coil, 3cm by 4 cm placed in a magnetic field of strength 0.1T. The coil rotates at 50 rev/sec. At a position when the magnetic field is perpendicular to the coil, calculate:

i) the amount of magnetic flux that passes through each turn
ii) the angular velocity of the coil and
iii) the peak voltage generated by the coil as it rotates

Source: Fiji Seventh Form Examination, 2006.

Problem is that the examiner gave answer to "ii)" as 1971.92 rad/sec. Which according to me seems incorrect.
But in the examiners report, he clear said that "100pi rad/sec" is not the correct answer.

2007-09-25 19:09:49 · 2 answers · asked by prashmanic 4 in Mathematics

2007-09-25 19:08:45 · 17 answers · asked by Priscilla A 1 in Mathematics

2007-09-25 19:08:01 · 4 answers · asked by Anonymous in Mathematics

1.
lim
x→ ∞ ( 4 ·x^7 −15 ·x^3 +5)/(c·x^n−3 ·x
^3+17)=4/7=0.571428571428571 .

calculate for c and n.


2.
Let f(x)=2 ·x^6 −12 ·x^3 +10 and g(x)=c·x^n−7 ·x^3 +20 with c ≠ 0. Then
lim
x→ ∞ f(x)/g(x)=0 implies that n either <, >, or = something. calculate something and complete statement.

2007-09-25 19:02:20 · 1 answers · asked by Anonymous in Mathematics

what does x equles?

2007-09-25 18:49:51 · 7 answers · asked by Anonymous in Mathematics

dy/dx= (cos x -sin x)^2

can I do that sum this way:

y= (cosx-sinx)^3 / 3(sinx + cosx)

2007-09-25 18:34:54 · 2 answers · asked by Chocolate Strawberries. 4 in Mathematics

Just to make sure I have the right answer. When doing a simple distillation, the reason why the liquid in the distillation flask doesn't evaporate all at once once the boiling point is reached is: the liquid distillated is separated from the volatile liquid still in the conical vile. You are purifying the liquid so not all the substance can be vaporized all at once.

2007-09-25 18:34:29 · 3 answers · asked by iheartdr.sambeckett 4 in Chemistry

2007-09-25 18:33:46 · 2 answers · asked by mandy 1 in Mathematics

hi I was thinking about the speed of light and Albert Einstein's theory of relativity. Now im not really into books and stuff and i go to an art school so this is totally out of my rage.But ill give it a shot .So lets assume that a space ship is going from point A to point B and the distance between is 1 year light.So the ship has to go at the speed of light to make it for one year to point B!! but since the theory don't allow the ship to go at the peed of the light because x factor ,,the ship will be going 70% the speed of light and it should be able to get to point B for little over a year but as the theory says ;time passes faster on earth than the space ship which is traveling at 70% the speed of light .I don't have the skills to figure it out how many years have passed on earth but a guess is 10 years.now imagine we can see the ship for all the distance it did and the ob vies answer is that we see the ship going 10 times slower than the speed of light . So what do u think????

2007-09-25 18:28:27 · 12 answers · asked by sardi p 1 in Physics

Are there variations of the pileated woodpecker colors here in Central Florida? Im trying to find out what kind of large woodpecker I saw on the space coast. Im pretty sure it's pileated..but...these ones in the books always look smaller and there is always a head of red feathers. The pileated woodpecker I've seen is only blue and white.

2007-09-25 18:27:45 · 3 answers · asked by mishmallow8 2 in Zoology

Hey i need help with a physics project

I have to make a device that can travel one meter and carry 1 kg of mass...

so the basic thing is

u set it down ( u can do something but cant push it ) and then it has to travel one meter carrying 2 pounds ...

any ideas?

no battery/electric,gas,rocket powered objects

i was thinking something elastic ? ( but of course not necessary )
please help if u know

2007-09-25 18:27:10 · 5 answers · asked by Jay a 2 in Engineering

2007-09-25 18:21:04 · 9 answers · asked by Anonymous in Weather

or better yet to store the energy from sunlight to light a bulb in the evening.

2007-09-25 18:20:06 · 3 answers · asked by bush l 1 in Other - Science

2007-09-25 18:12:22 · 3 answers · asked by cabingirl 2 in Earth Sciences & Geology

i have sqrt(2x-x^2) and am trying to move it right by 3 units

2007-09-25 18:11:06 · 2 answers · asked by zack 1 in Mathematics

1) 2(2.5b - 9) + 6b = -7

2)12y = 2y + 40

3) 6(c + 4) = 4c - 18

4) 0.7w + 16 + 4w = 27.28

5)24 = -6(m + 1) + 18

6)0.5m + 6.4 = 4.9 - 0.1m

7) 77k - 8 + 2(k + 12) = 52

2007-09-25 18:06:09 · 1 answers · asked by Anonymous in Mathematics

A typical formulation for window glass is 75% SiO2, 15% Na2O, and 10% CaO by mass.

What masses of sand (SiO2), sodium carbonate, and calcium carbonate must be combined to produce 1.00 kg glass after CO2 is driven off by thermal decomposition of the carbonates?
(Express your answers to 1 decimal place.)

Mass of sand (in grams) 1.-----
Mass of sodium carbonate (in grams) 2.-----
Mass of calcium carbonate (in grams) 3.-----

2007-09-25 17:59:55 · 1 answers · asked by Ahmed A 1 in Chemistry

If a planet were the same size as Earth, but twice as massive, and you weighed 100 pounds on Earth, what would you weigh there?

2007-09-25 17:56:40 · 5 answers · asked by chrisray 3 in Astronomy & Space

http://s5.photobucket.com/albums/y186/ebaytemp/?action=view¤t=MathGrid.jpg
I think it's 24 because 3 and 6 are both factors of 24. I need to know so I can send my boy to bed. It's been way too long for me. Does anyone know FOR SURE?

2007-09-25 17:56:32 · 4 answers · asked by Cynthia E 2 in Mathematics

Just curious, but can anybody prove to me why a triangle is 180 degrees? Thanks in advance.

2007-09-25 17:53:51 · 4 answers · asked by Kwang Joon R 2 in Mathematics

find the roots of the equation

z^2 - z + 1 =0, giving answers in the form x +iy where x and y are real

Thanks

2007-09-25 17:53:34 · 8 answers · asked by Mystic healer 4 in Mathematics

2007-09-25 17:49:36 · 6 answers · asked by Peter N 1 in Medicine

If the answer is already found, why the world scientists are not conducting gene correction to imbibe 'honesty' in every living brain?

2007-09-25 17:48:21 · 1 answers · asked by viswamvishnu 3 in Medicine

hi I was thinking about the speed of light and Albert Einstein's theory of relativity. Now im not really into books and stuff and i go to an art school so this is totally out of my rage.But ill give it a shot .So lets assume that a space ship is going from point A to point B and the distance between is 1 year light.So the ship has to go at the speed of light to make it for one year to point B!! but since the theory don't allow the ship to go at the peed of the light because x factor ,,the ship will be going 70% the speed of light and it should be able to get to point B for little over a year but as the theory says ;time passes faster on earth than the space ship which is traveling at 70% the speed of light .I don't have the skills to figure it out how many years have passed on earth but a guess is 10 years.now imagine we can see the ship for all the distance it did and the ob vies answer is that we see the ship going 10 times slower than the speed of light . So what do u think????

2007-09-25 17:46:03 · 11 answers · asked by sardi p 1 in Astronomy & Space

What is the domain? How did you get it?

2007-09-25 17:40:35 · 4 answers · asked by Meowmix 2 in Mathematics

How does one substrate react at the enzyme's active complex without another substrate? Does it react with the enzyme?

But I thought enxymes are defined as catalysts that AREN'T used in the reaction itself...? So there are 3 reactions that occcur before the product is finished?

HELP ME!!

cofactors, coenzymes ahhh it's all so confusing!

Thanks =)

2007-09-25 17:40:09 · 3 answers · asked by justmyinput 5 in Biology

If anyone could explain how the following is done, it would be greatly appreciated!

Prove that in any primitive Pythagorean triple (a,b,c) either a or b must be a multiple of 3.

2007-09-25 17:38:26 · 3 answers · asked by Teah 1 in Mathematics