Science & Mathematics - 21 September 2007

a scateboarder rolls down a hill with the acceleration of 4.0m/s2(squared). he is on a hill for 4.8s (seconds). what is the change in his speed ?

m-meters s-seconds
explain in full detail formula

2007-09-21 04:18:53 · 5 answers · asked by Anonymous in Mathematics

2007-09-21 04:18:44 · 8 answers · asked by Maya 1 in Physics

2007-09-21 04:16:26 · 15 answers · asked by gumtrunk 2 in Biology

It has been a long time since i took the principles of chemistry and am currently retaking them. i just want to verify.

I am asked:

What ions are present in the compound Mg3N2?

i know that 1 mg contains 2 anions and N contains 3 anions if i am not mistaken. does all this mean that i just multiply the 2 Mg anions by 3 and get 6 anions for Mg and 6 anions for N for a total of 12 anions?

2007-09-21 04:15:13 · 4 answers · asked by john s 3 in Chemistry

I have just seen an unusual Bee fly passed me... it was red in colour and made the same sound as a Bumble Bee... it looked more like Denis the Menis than the English Garden bee any ideas what type it could bee lol?

2007-09-21 04:14:13 · 8 answers · asked by Anonymous in Physics

A few years ago, a small common lizard got stuck between the screen and glass of a window in my house and died. He's been sitting there all that time and we call him the nameless lizard that haunts the window. Recently I'd decided to honor his memory with some kind of artsy project involving the preservation of his skeleton, but I have no idea how to go about doing this!
Could someone help me?
Thanks so much!

2007-09-21 04:11:45 · 3 answers · asked by sadie911 2 in Zoology

2007-09-21 04:10:59 · 4 answers · asked by kylegaston13 1 in Engineering

2007-09-21 04:10:41 · 14 answers · asked by mr_bob 1 in Astronomy & Space

Do they know who they are?Is it an informed decision, not to pass-over?

2007-09-21 04:09:38 · 11 answers · asked by Dr. NG 7 in Paranormal Phenomena

What are each of these Homogeneous or heterogeneous?
Thanks for your help!!!
Orange Juice
Tap Water
Steel
Air
Raisin Muffins

2007-09-21 04:09:14 · 6 answers · asked by Ray 2 in Chemistry

2007-09-21 04:06:39 · 10 answers · asked by not_omniscient_enough 1 in Biology

with the aid od the diagram of the wate cycle explain how water s a renewable resource
would you say something llike
the suns heat evaporates sea water , forming a gas called water vapour, the light water vapour rises into the sky and forms a cloud. sea winds blow the clouds inland where they continue to rise forming rain or sleet rivers and ground water return moist

2007-09-21 04:02:34 · 2 answers · asked by Anonymous in Earth Sciences & Geology

two blocks: b1=3kg, b2=1kg;
frictionless surface; massless pully, massless cord
b1, in a flat surface, force --> = 2.3 N

__b1------------------O <--pulley.
_____________ __`_.
floor_ _____________`b2

b2 is at an angle of 30 degrees from floor to pulley

a) need tension of cord above,

Also, b) what is the biggest value the magnitude of F--> may have w/out the cord becoming slack.

notes: confused about where the Sine goes in the equation for part "a)"

2007-09-21 03:56:56 · 2 answers · asked by Ar J 2 in Mathematics

Alright. I have to convert two decimal numbers into binary. And then add them together. Then I have to show that the sum of the binary numbers is = to the sum of the decimal numbers.

Ok the numbers are 257 & 431. Their sum is 688.

I am sooo close on this but for some reason I'm just one number off. Can you please help me???? PLEASE??

Also am I right in that 688= 1010110000?

THanks in advance.

2007-09-21 03:46:21 · 5 answers · asked by I Ain't Your Momma 5 in Mathematics

Snowballs are thrown with a speed of 13 m/s from a roof 7 m above the ground. Snowball A is thrown straight downward; snowball B is thrown in a direction 25 degrees above the horizontal. (A) Is the landing speed of snowball A greater than, less than, or the same as the landing speed of snowball B? Explain. (B) Verify your answer to part a by calculating the landing of both snowballs.

2007-09-21 03:43:17 · 1 answers · asked by mmeee 1 in Physics

Let's say we went back in time to the beginning of the universe and everything is created in exactly the same way. Then the Earth is formed and it revolves around the sun in the same way, but now everything is randomized. Would the world be exactly the same as it is now? That is to say that is it by some sort of destiny that we are here or rather by random chance of one in a billion odds?

More specifically, would all life require DNA to reproduce? Would the same human inventions be invented at the same time? Would computers use a non-binary system? The possibilities are endless, or are they?

2007-09-21 03:38:42 · 6 answers · asked by James H 2 in Astronomy & Space

What line of latitude divides Earth into Northern and Southern Hemispheres?

2007-09-21 03:30:34 · 6 answers · asked by adbfgav b 1 in Geography

Which of the following statements is/are true concerning orbital overlap bonding, and carbon hybridization.

A. The sp^3 hybrid has one electron "left over" (i.e. not used in the hybrid)

B. The overlap between an electron is a sp^2 hybridized orbital, and an electron in a (s atomic orbital) is called a pi bond.

C. The shape of sp hybridized orbitals dictates 120 degree angkes between bonds

D. In carbon-carbon bonds, the maximum amount of orbital overlap requires that the (p orbitals) are perpendicular to each other.

E. The shape of the sp^3 hydridized orbitals is tetrehedral

F. More than one of the above

G. None of the above

2007-09-21 03:29:41 · 4 answers · asked by Cayden 1 in Chemistry

2007-09-21 03:29:06 · 10 answers · asked by soumyajit paul 14 1 in Astronomy & Space

Suppose atoms at rest emit visible light with a wavelength of 500 nm. At what wavelength would the light from the atoms be observed if the atoms were moving toward the earth at a speed of 20,000 km/s?

2007-09-21 03:21:45 · 3 answers · asked by New Mommy 1 in Physics

Of course you do! So what if current physics laws tell us its not possible.

2007-09-21 03:11:02 · 15 answers · asked by Anonymous in Astronomy & Space

I have a school proyect where i need to collect all these natural things based on the color wheel. For example, Carrot is orange, peas are green color some leaves also contain green colors. These are the colors i have dificulty:
Blue, Gray Blue, blue green

2007-09-21 03:08:58 · 10 answers · asked by Pit 1 in Botany

I know that the electronic ballast can convert the frequency up to a few KHz, but how could I obtain a higher frequency AC source at the MHz Range?

2007-09-21 03:07:58 · 3 answers · asked by nakazawa 1 in Engineering

2007-09-21 03:04:08 · 9 answers · asked by smilek 1 in Astronomy & Space

2007-09-21 03:01:14 · 6 answers · asked by Victor D 2 in Astronomy & Space

2007-09-21 02:57:13 · 5 answers · asked by nickmydog 1 in Mathematics

2007-09-21 02:56:41 · 4 answers · asked by nickmydog 1 in Mathematics

Hi my friend has gall stones but i dnt wanna ask him what is it, cuz i scared it might upset him or something.

Do u know what it is?

2007-09-21 02:53:06 · 9 answers · asked by linetta 2 in Medicine

How far would I be able to fly?

2007-09-21 02:53:00 · 10 answers · asked by Bill W 【ツ】 6 in Physics

Should I trust http://www.quackwatch.org as a Guide to Quackery and Health Fraud?

2007-09-21 02:52:52 · 5 answers · asked by sami 3 in Medicine