Science & Mathematics - 15 August 2007

Has there ever been a design that only used magnets as a power source to power a car?
I developed this design(only on paper so far) to power a car using nothing but magnets as a power source. Has this been done yet? If so was it successful, if not, why? The only major problem I can think of so far with this design is metal objects flying across the road being attracted to the car.

2007-08-15 10:01:53 · 5 answers · asked by nick 1 in Engineering

If the answer is irrational, please give the answer as a simplified radical, not as a rounded decimal.

x^2 + 3x = 12




The following equation is in Standard form.

Put the equation in General form by completing the square.

Tell the vertex of the parabola.

Please use ^ for exponents.

f(x)= x^2 - 4x + 7

2007-08-15 09:58:14 · 5 answers · asked by Anonymous in Mathematics

Why do you think chemistry is sometimes called the central science?

2007-08-15 09:52:46 · 3 answers · asked by dude d 1 in Other - Science

3x+3y=12

solve for y

2007-08-15 09:43:26 · 4 answers · asked by JOGOO 2 in Mathematics

Anyone know what the electron geometries of Phosphorus Trifluoride & Phosphorus Pentafluoride are? Also, what are their polarity?

2007-08-15 09:40:52 · 5 answers · asked by Verushka 1 in Chemistry

1. i^5

2. sqrt - 32 (remember to deal with the negative under the radical first)

3. sqrt - 25 - sqrt - 49

4. (-3i)(2i)

5. (7 sqrt -3)(2 sqrt -27)

6. sqrt -24 / sqrt - 2

thank you all so much. if anyone solves all of them i will most definetly award a best answer.

2007-08-15 09:40:18 · 3 answers · asked by Anonymous in Mathematics

2007-08-15 09:40:14 · 23 answers · asked by Anonymous in Weather

2007-08-15 09:38:42 · 6 answers · asked by andrea s 1 in Mathematics

4 students own the following # of calculators

Student A, B, C, D
# of calc 2, 1, 4, 3

-Find the mean and standard deviation:

-2 randon samples where drawn calculate mean and standard dev.

2007-08-15 09:38:42 · 6 answers · asked by Jsmith07 2 in Mathematics

any help would be appreciated

2007-08-15 09:37:02 · 5 answers · asked by Cammy 1 in Mathematics

2007-08-15 09:35:07 · 6 answers · asked by Myia M 1 in Mathematics

2007-08-15 09:35:04 · 24 answers · asked by Anonymous in Weather

I first read this from a book then i asked my freind and he said he heard it before as well and that our days, weeks and years arn't quite right and thats why we have leap years.
So its not the 24 hr day then really...

2007-08-15 09:33:53 · 19 answers · asked by ? 6 in Other - Alternative

Suppose that we have a regular polygon with 'n' sides. 'M' is an arbitrary point in this polygon whose distance from the sides of the polygon are 'x_1', 'x_2', ..., 'x_n'.

Show that this equation holds:
http://m1.freeshare.us/167fs644292.gif

where 'a' is the length of each side.

2007-08-15 09:33:34 · 3 answers · asked by Amir 1 in Mathematics

Can you envisage a future world where humans no longer had to work (they could do some part-time work if they enjoyed it or wanted extra money, but did not have to to get by)? Can you see the positives of a world where computers, robots & machines (which are eventually moslty owned by the state) make and sell products and services earning enough money to pay everyone's basic bills (groceries, tax, rent, water & electricity)? What if ...

2007-08-15 09:21:13 · 8 answers · asked by Wise Kai 3 in Engineering

i am adding vectors and once i do all the junk and get an answer like -82.19, how do i know what quadrant it is in. because i know that q.1, i don't add anything but the other three i do, just how do i know the quadrant?

thanks!

2007-08-15 09:17:59 · 4 answers · asked by Elizabeth 3 in Physics

2007-08-15 09:13:28 · 19 answers · asked by Alexander 6 in Mathematics

In the United States, 8 percent of African Americans are carriers for the sickle-cell allele, while in central Africa the figure is 20 percent. What could account for this difference? Assess.

2007-08-15 09:10:39 · 6 answers · asked by Raphel M 1 in Biology

I live in the US, and I've always wondered if it snows over in the UK. If so, how much?

2007-08-15 09:10:34 · 3 answers · asked by Tikimaskedman 7 in Weather

Martina leaves home at 9 A.M., bicycling at a rate of
24 mi/h. Two hours later, John leaves, driving at the rate of 48 mi/h. At what time
will John catch up with Martina?

2007-08-15 09:09:45 · 4 answers · asked by Anonymous in Mathematics

I never really thought about this before so I was just wondering.

2007-08-15 09:08:34 · 7 answers · asked by Oceangrl03 2 in Zoology

With nuclear weapons, man can surely leave the Earth void of life.

However, can man actually totally destroy the planet?

Could the nuclear blasts take the planet off course, leaving it a barren rock?

2007-08-15 09:06:00 · 16 answers · asked by Paul222@England 5 in Earth Sciences & Geology

Find the pH of lemon juice. Using the pH, show how to find the hydrogen ion content by using the logarithmic formula. Round to 10 decimal places.can you please help?

2007-08-15 09:01:54 · 7 answers · asked by pp1976 1 in Chemistry

When 2x^(2a) + 11(x^a)(y^b) - 6y^(2b) is factored, one factor is:

2x^(2a) - 3y^b

x^(2a) + 2y^b

2x^a + y^b

x^a + 6y^b

none of these

2007-08-15 09:01:41 · 2 answers · asked by piper h 1 in Mathematics

when a solid is heated the mollecules expand and move apart in each stage, therefor when you freeze water, it should shrink as the mollecules get closer together to become a solid. anyone know why it expands instead?

2007-08-15 09:01:31 · 13 answers · asked by Anonymous in Physics

I live there what is it going to do?

2007-08-15 08:57:50 · 7 answers · asked by Anonymous in Weather

How would you prepare 1.00L of a 0.50M solution of each of the following?

a) NiCl2 from the salt NiCl2 . 6H20

I know I have to find the molar mass, as advised by other people, but the problem is that I don't know whether or not to include the 6H2O into it if the question said NiCl2 from the salt NiCl2 . 6H20.

Thank you so much in advance if you can help me out with this question.

2007-08-15 08:56:59 · 2 answers · asked by Andrew 2 in Chemistry

I know animals adapt to their environment, ie the birds in the Galapagos island whos bills are changing shape to suit the food they eat. There are other examples of adaptation like this but no proof as far as I know with evolution, ie an animal changing into another species. Correct me if I am wrong! Also provide proof.

The idea of humans evolving into humans as we know today within the short period of 4 billion years is a hard pill to swallow. Especially when supposidly it would take a single cell organism 150 million years to evolve into a multi cell organism. Then only 26 times longer to reach human stage. That is assuming single cell organisms were here when the earth was made 4 billion years ago. It just doesn't make sense. Where did we come from is the answer everybody wants to know?

2007-08-15 08:56:52 · 21 answers · asked by Halox 3 in Earth Sciences & Geology

in electrical terms

2007-08-15 08:49:34 · 3 answers · asked by biliana 1 in Engineering

dynamic equilibrium
recombination of chromosomes

Plz make the definitions has basic has possible
Any help,much appreciated

2007-08-15 08:45:17 · 2 answers · asked by Skillz 2 in Biology