Science & Mathematics - 20 November 2007

submerged in water. What is the density of the object?

Density of water = 1000 kg/m^3

2007-11-20 15:23:39 · 4 answers · asked by Pascal 4 in Physics

pd hasn't been on Y/A (even other sections) in 4 days. Just beginning to get worried about him. Maybe he's just taking a "Yahoo coffee break"! Hope he's o.k. Do you know?

2007-11-20 15:23:06 · 9 answers · asked by Deenie 6 in Paranormal Phenomena

if 1500$ is invested now at 7% per annum compounded annually. when will it reach $3150?

2007-11-20 15:22:40 · 2 answers · asked by Anonymous in Mathematics

Is it possible to force with strength two North(or south) poles of two separate magnet to be touching each other ?
If yes what will happen if we release them from touching ?

2007-11-20 15:21:58 · 11 answers · asked by karta s 2 in Physics

Please tell me if the affects to the human body from exposure to Beta radiation is the same as Alpha or Gamma radiation. If it is not, then please describe the effects of Beta radiation.

2007-11-20 15:20:42 · 2 answers · asked by Asian Boy 2 in Physics

A 0.187 kg mass is attached to a spring and executes simple harmonic motion with a period of 0.27 s. the total energy of the system is 2.5 J. Find the force constant of the spring.

2007-11-20 15:20:23 · 2 answers · asked by Yami 1 in Physics

So I'm trying to make crystals with salt in a supersaturated solution. It seems to work, I DON'T boil the water, but for some reason, all the solution does is sinks down to the bottom like a salt dust. What am I doing wrong? Why wont my crystals form?

2007-11-20 15:19:12 · 2 answers · asked by Lalavava 1 in Chemistry

I really really really really really want to make a wish over a shooting star. When will they come out?

2007-11-20 15:18:37 · 9 answers · asked by Anonymous in Astronomy & Space

2007-11-20 15:17:23 · 3 answers · asked by Ariel B 1 in Mathematics

In the city of Sonoma CA, there is a row of trees on 2nd Street that produce a Fall crop of fruit that is chartreuse and yellow . The tree looks like a Cottonwood tree (not as tall) and the fruit resembles a human brain, varying in size from a softball to a large Grapefruit. It smells like a cross between a pineapple and pine tree. I have trepidation about eating this fruit as I cannot find any reference to it's toxic nature.

2007-11-20 15:15:46 · 4 answers · asked by Kamp 4 in Botany

1. How do intrusive rocks differ in origin from extrusive rocks?

2. How are polymineralic rocks different from monomineralic rocks? Please give examples of each...

last question..... x)

3. How are all rocks ultimately derived from magma?

2007-11-20 15:14:28 · 3 answers · asked by Anonymous in Earth Sciences & Geology

The question is "Solve the equation 4 sin^2 (x) − 3 = 0."

I got to the point sin(x) = +/- sqr(3)/2
Do I solve for the positive or the negative or both??

2007-11-20 15:14:00 · 8 answers · asked by Matt S 1 in Mathematics

2007-11-20 15:11:05 · 5 answers · asked by Anonymous in Physics

2007-11-20 15:10:50 · 8 answers · asked by Anonymous in Astronomy & Space

The tank of radius A contains water that has a max depth H, volume V of water in the tank is V=(1/3)pi(H^2)(3A-H). Now the tank has radius 16 feet and is being filled at rate of 13.37 ft^3/min. What is the rate when the water is rising at H= 4ft

I know how to do related rates and got almost everything down, but I just don't know how to start this problem

2007-11-20 15:06:59 · 3 answers · asked by ahhhhmath 2 in Mathematics

i have a project and i need to know if it will i have to turn in background research to my teacher

2007-11-20 15:04:42 · 1 answers · asked by Anonymous in Chemistry

2007-11-20 15:04:35 · 6 answers · asked by tyar 2 in Physics

y = ce^-2x + e^-x is solution of equation y' + 2y = e^-x

Find constant c so the solution satifies initial condition y(-2) = 5

2007-11-20 15:00:47 · 4 answers · asked by Gills 1 in Mathematics

Asking those that have actual knowledge of the capabilities of the equipment. Not intended to start a moon landing hoax debate. Thanks!

2007-11-20 14:59:48 · 4 answers · asked by Just Me 2 in Astronomy & Space

2007-11-20 14:56:51 · 4 answers · asked by Baby Gurl 1 in Physics

2007-11-20 14:55:16 · 5 answers · asked by klyre s 1 in Physics

a. 1 gram
b. 10 grams
c. 1 kilogram

2007-11-20 14:53:29 · 6 answers · asked by Anonymous in Chemistry

There are two difficulties I'm having. First, the problem itself:

For the following problem, (a) Find the intervals on which f is increasing or decreasing, and (b) Find the local maximum and minimum values of f.

14. f(x) = cos^2(x) - 2*sin(x), 0 =< x =< 2*pi

I've come up with the following critical points: 0, pi/2, 4 - 5(??), and 2*pi. First of all, I don't know what's up with the 4 - 5 interval, I mostly discovered it by graphing, though I think something led me to examine it initially. It seems to hold the absolute maximum. How would I actually analyze and find information about that interval? Secondly, how does one fully analyze a trigonometric function? I see that they put it on an interval, so I assume that one should just work through cases? Obviously at this point I can't just algebraically solve the equation for zero.

Any help is appreciated! Thanks!

2007-11-20 14:50:45 · 2 answers · asked by oatmealia 2 in Mathematics

2007-11-20 14:49:51 · 6 answers · asked by alecxandria f 1 in Zoology

2007-11-20 14:49:32 · 3 answers · asked by Sleepyguy 4 in Biology

Hi, my question is:
x 4 (x to the fourth power) - 625
x4-625

I jsut dont get how to factor fully. Thanks.

2007-11-20 14:44:54 · 7 answers · asked by DeMoN 2 in Mathematics

2007-11-20 14:44:13 · 1 answers · asked by Jesse 1 in Biology

I recently did an experiment and It was affecting the temperature on enzyme activity. one would expect that the graph would increase and then hit a point of denaturation and then decrease. This happened excpet for at the point of 40 C it decreased slightly and then increased again. What could be the cause of this?

2007-11-20 14:42:53 · 2 answers · asked by Anonymous in Biology

A machine gun is attached to a railroad flat car that rolls with negligible friction. If the railroad car has a mass of 6.25 X 10 to the 4th power kg, how many bullets of mass .025 kg would have to be fired at 250 m/s off the back to give the railroad car a foward velocity of .5 m/s?
A. 400
b 2000
c 3000
d 5000

2007-11-20 14:41:04 · 1 answers · asked by S.I.N 4 in Physics

2007-11-20 14:36:42 · 2 answers · asked by aznboi6623 1 in Chemistry