Science & Mathematics - 14 October 2007

Two blocks are attached to each other. The mass of the first block is 80.0kg and its density is 1071 kg/m^3. The density of the second block is 120 kg/m ^3.

What is the volume of the second block if the arragement is barely afloat in water?

2007-10-14 13:52:45 · 1 answers · asked by Anonymous in Physics

A system contracts from an initial volume of 15.0 L to a final volume of 10.0 L under a constant external pressure of 0.800 atm. The value of w, in J, is

2007-10-14 13:52:44 · 1 answers · asked by cpistone7 2 in Chemistry

My planet is 3000 light years ahead of pluto surround by to black holes and is moving away from the Milkway Galaxy's orbit.

2007-10-14 13:51:14 · 5 answers · asked by Kandai M 2 in Astronomy & Space

2007-10-14 13:50:54 · 1 answers · asked by xvxnishaxvx 1 in Earth Sciences & Geology

Factorize:
(i) 2x^2-x+1/8
(ii) a^2 + 7xy + 12y^2
(iii) 2x^4 - 7x^3 + 3x^2 + 63x - 45

2007-10-14 13:49:20 · 2 answers · asked by besst_gal 1 in Mathematics

An airplain is flying at 240m/s at an angle of 30 degrees with the horizontal. when the altitude of the plane is 2.4km, a flare is realiease. the flare hits the target on the ground, wat is the angle?

How do i even approach this i feel as if there isn't enough info

From a 60m cliff a rocket is launched upwards with Vo = 23 m/s at an angle of 50 degrees with respect to the horizontal. At what point above the ground does the rocket strike the wall of a vertical cliff located 20m away?

2007-10-14 13:48:30 · 1 answers · asked by Anonymous in Physics

An ideal gas is confined in a cylinder at 20 C and a pressure of 4 atm.

1. If the cylinder is surrounded by boiling water and allowed to come to equilibrium, what will the pressure of the gas be?

2. If the gas is allowed to escape until the pressure again reaches 4.0 atm, what fraction of the original gas, by weight, will escape?

3. If the temperature of the remaining gas now returns to 20 C, what is its pressure?

I'm so lost, please explain and show your work so that I may follow.

2007-10-14 13:48:22 · 1 answers · asked by Anonymous in Physics

A 4.5 kg block slides down a frictionless incline
making an angle of 31degrees with the horizontal.
The acceleration of gravity is 9.81 m/s^2
a) Find the work done by the gravitational
force when the block slides 4.1 m (measured
along the incline). Answer in units of J

b) What is the total work done on the block?
Answer in units of J.

c) What is the speed of the block after it has moved 4:1 m if it starts from rest? Answer in
units of m/s.

d) What is its speed after 4.1 m if it starts
with an initial speed of 1.4 m/s? Answer in
units of m/s.

I know it seems like a lot - I'm not asking for answers, just a little guidance on what equations to use - I'm sure i can figureit out then... Thanks so much!

2007-10-14 13:47:41 · 1 answers · asked by Anonymous in Physics

A firecracker is tossed straight up into the air. It explodes into three pieces of equal mass just as it reaches the highest point. Two pieces move off at 120 m/s at right angles to each other. How fast is the third piece moving?

2007-10-14 13:46:28 · 1 answers · asked by Jerry M 1 in Physics

2007-10-14 13:46:16 · 2 answers · asked by Anonymous in Earth Sciences & Geology

How would you find the general term for the linear sequence where a=5 and t8=43.5

2007-10-14 13:45:31 · 1 answers · asked by Anonymous in Mathematics

Can you find a polynomial with integer coefficients with root(3,3) - root(2,5) as root?

By root(x,n), I mean the nth root of x.

2007-10-14 13:44:27 · 1 answers · asked by Brian S 2 in Mathematics

I have to find the coefficient of knietic friction between a shoe and a wooden board. I have managed to get the static friction by placing the shoe on the board and raising it until the shoe starts moving. The only materials I can use is the wooden board, shoes and a metre stick. I have tried one way, but my teacher says it isn't accurate enough, and I haven't been able to devise an experiment that would help me find the coefficient of kinetic friction. If anyone has some tips or ideas on how to do this, I would be very grateful for their help.

2007-10-14 13:43:09 · 1 answers · asked by smiley5671 2 in Physics

2007-10-14 13:43:05 · 1 answers · asked by cnfer657 1 in Chemistry

I will be tested on this in 2 weeks so I am practicing.
For CO2 ,would the carbon be at either a +4 or a +2 because the oxygen is -2 or -1 or would the oxygen be a -4 or -2 because it is two oxygen molecules.

For Na2CO3 , the sodium is 1 x 2 = +2, the oxygen is 3 x -2 = -6 ,so the carbon would have to be +4 to balance it out?
THANKS

2007-10-14 13:39:33 · 1 answers · asked by Boo Radley 4 in Chemistry

Find the vertex either by writing the parabola in standard form or using the vertex formula.

f(x) = x^2-16x +3

2007-10-14 13:33:50 · 5 answers · asked by Anonymous in Mathematics

2007-10-14 13:28:47 · 2 answers · asked by lirael1019 1 in Chemistry

What are the current theories as to why its all over the place? Not "because the more mass you've got the more gravity" but why does mass have gravity in the first place.

Also is it theoretically possible to make energy from gravity? It sound plausible since gravity is like a force... but im guessing the reason this isn't considered much is because it goes against the laws of thermodynamics, i think, right? Or is it a possibility??

2007-10-14 13:28:24 · 3 answers · asked by Anonymous in Physics

I got it from this article: http://news.nationalgeographic.com/news/2007/08/070808-largest-planet.html

2007-10-14 13:24:56 · 3 answers · asked by futuregeek1 1 in Astronomy & Space

are hydrocarbons held togther by ionic or hydrogen bonds? also, are they hydrophic? polar or non polar?

2007-10-14 13:23:10 · 5 answers · asked by noctem55 1 in Chemistry

2007-10-14 13:17:01 · 5 answers · asked by hunedip22 1 in Mathematics

2007-10-14 13:16:23 · 9 answers · asked by hunedip22 1 in Mathematics

It was evening, the sun was starting to set, there was cloud cover, but it was white. Through the clouds we saw a vertical rainbow! It had not rained anywhere as far as we know, and I was just wondering if the moisture from the clouds was enough to form a rainbow.

2007-10-14 13:16:07 · 4 answers · asked by fredsredhead66 4 in Weather

How has modern civilization accelerated this cycle?

2007-10-14 13:14:54 · 5 answers · asked by George A 5 in Earth Sciences & Geology

How do hot spots and plate tectonic theory account for the fact the hawaiian island varyin age

2007-10-14 13:12:36 · 1 answers · asked by Anonymous in Earth Sciences & Geology

I was just wondering how many glaciers are on Mount Baker. If you could also give a souce from where you got the answer from, that would be helpful too.

2007-10-14 13:10:31 · 1 answers · asked by ExpertTechAnswers 2 in Geography

Find the variable and write an equation to model each situation. Then solve.

2 buses leave New York at the same time and travel in opposite directions. One bus averages 55 mph and the other bus averages 45 mph. After how many hours will the buses be 400 apart?






help!

2007-10-14 13:09:55 · 5 answers · asked by robertxlove 3 in Mathematics

Can you tell me how to get...how to get to Sesame Street.

2007-10-14 13:07:58 · 3 answers · asked by Anonymous in Geography

thanks!

2007-10-14 13:07:56 · 4 answers · asked by Anonymous in Astronomy & Space

2007-10-14 13:05:17 · 6 answers · asked by homeworkhelper 1 in Astronomy & Space