Science & Mathematics - 30 July 2007

A beam of plane-polarized microwaves is incident upon an aerial which is positioned to give maximum response. The aerial is rotated at an angle of 30 degrees to the plane of polarization about the direction of the incident waves.
Calculate the % reduction in the amplitude of the signal now received from the aerial.

2007-07-30 10:45:49 · 1 answers · asked by polol 2 in Physics

Perform the indicated operation. Simplify if possible.
(2) / ( x + 4) + (9) / (5x + 20 )

(19) / (5x + 4)^2

(11) / (5x + 4)

(47) / ( 5x + 4)

(19) / ( 5x + 4)

2007-07-30 10:43:59 · 2 answers · asked by Anonymous in Mathematics

A compass has a magnetized needle inside of it that points to magnetic north. What keeps the needle from being effected by metal around it? Is it the liquid inside?

2007-07-30 10:41:27 · 4 answers · asked by robertlash19 2 in Physics

Leopard Seal Vs Orca ?

2007-07-30 10:40:41 · 4 answers · asked by Anonymous in Zoology

Can steam be heated to the point in which the steel or iron container would reach it's melting point? I understand that the heat of the steam will increase with pressure, does it turn into plasma at some point?

2007-07-30 10:37:22 · 4 answers · asked by Charles B 1 in Chemistry

Determine the heat of reaction for the decomposition of one mole of benzene to acetylene C6H6(l)-->3C2H2(g) given the following thermochemical equations:

2C6H6(l)+15O2(g)-->12CO2(g) + 6H2O(g) Delta H = -6271kj
2C2H2(g)+ 5O2(g)-->4CO2(g) 2H2O(g) Delta H = -2511kj

2007-07-30 10:33:16 · 3 answers · asked by Anonymous in Chemistry

I love the smell in the air just before it starts raining... but I wonder why the sweetness in it?? Where does it come from??

2007-07-30 10:32:44 · 5 answers · asked by anya 1 in Weather

A highway patrol airplane flies 3 mi above a level, straight road at a constant rate of 120 mph. The pilot sees an oncoming car and with radar determines that at the instant the line-of-sight distance from plane to car is 5 mi the line-of-sight distance is decreasing at the rate of 160 mph. Find the car's speed along the highway.

The answer in the back of the book is 80 mph. I have no idea where to start.

2007-07-30 10:30:58 · 3 answers · asked by salmonella_jr 3 in Mathematics

We just killed an enormous black widow in our gargage. Does that mean there are probably others there that we haven't seen yet?
We don't live in a rural area, and haven't seen many spiders since we moved into our house 2 years ago. 90% of the ones we have seen have been innocent daddy longlegs types.
Does it work the same with spiders as other creatures? Like how if you see one cockroach, that means there are dozens more you haven't seen?
Thanks in advance!

2007-07-30 10:30:23 · 9 answers · asked by eileezy2002 4 in Zoology

2007-07-30 10:22:52 · 10 answers · asked by Anonymous in Mathematics

Should not the creation of such a complex creatures be a clear evidence of the existence of God?

2007-07-30 10:20:40 · 23 answers · asked by Anonymous in Biology

the formula for the surface area of a sphere is 4πr^2 (π is pi by the way, it looks weird here), but i was wondering... what is the radius exactly? would it be wrapping a belt around a ball and cutting that in half or driving a stick through the middle to get through the other side, and taking half of that? (in other words half of the equator or half the axis?)

2007-07-30 10:19:20 · 7 answers · asked by Fundamenta- list Militant Atheist 5 in Mathematics

by throwing Brussel sprouts into the tank tracks? or was it walnuts I can never remember. "Vor sprig dik Ticktock" as they say with a speech impediment.

2007-07-30 10:16:19 · 10 answers · asked by Anonymous in Engineering

2H2O(g) -----> 2H2(g)+O2(g)

2007-07-30 10:13:41 · 2 answers · asked by Silvina M 1 in Chemistry

Is there any real debate among biologists whether life begins at conception? I'm told that the human zygote meets all 7 of the characteristics of a living organism (Movement, respiration, sensitivity, nutrition, excretion, reproduction, growth).

So is there a consensus among scientists? Biologists? Embryologists? Does the majority believe that life begins at conception?

Sources are appreciated!

Thanks.

2007-07-30 10:12:16 · 5 answers · asked by Hilary H 1 in Biology

1. Find the slope of the line that passes through the points (2, 3) and (5, 8).




2. Find the equation of the line that passes through the points (3, -2) and (4, -2).




3. Find the equation, in standard form, with all integer coefficients, of the line perpendicular to x + 3y = 6 and passing through (-3, 5).

1. Simplify and evaluate:
(42x3y-2z-3/x-5y8z-9)2




2. Convert to scientific notation (here you may use x as multiplication):
0.00083




3. For f(x) = 6x – 7, find f(2).




4. Perform the indicated operations:
(-x2 – 6x + 3) – (-9x2 + x – 1) – (x2 + 5x – 2)




5. Use FOIL to multiply:
(8x – 1)(2x + 5)




6. Multiply:
(x4 – 4x2 – 5)(x2 – x + 2)

Thank you so much in advance. I know there are alot of math whizs out here much smarter than me. Please help me out, much love and appreciation!

2007-07-30 10:04:46 · 4 answers · asked by princessmommy05 2 in Mathematics

I am going to start walking around my neighborhood regularly for exercise, because I don't have transportation and can't go to a gym. But the problem is that my neighborhood has taken a bit of a backslide, and it is no longer safe for me to be out at night by myself when it's dark. So, if it's not too much to ask, I would like a year-round schedule (maybe month-by-month?) of when it starts to get dark, so that I can plan my walking routine and avoid being out in the dark by myself. Any help you can offer would be great! Thanks!

2007-07-30 09:58:48 · 1 answers · asked by Deanna 3 in Earth Sciences & Geology

Like, Theoretically, if someone started working on a cyborg, on the basic components of a cyborg in their home, and did not live near a university, what could they do to improve and develop it better?
Websites, links on electronic circuitry, robotics history, resources, universities that specialize in this, models and studies done, etc???

2007-07-30 09:57:55 · 2 answers · asked by Anonymous in Physics

Each star is a sun millions of miles away.If every sun has as many planets around it as our sun is it possibe there is life out there some where. I would like to think so.How about you.

2007-07-30 09:55:49 · 39 answers · asked by Anonymous in Astronomy & Space

I have heard on the grapevine that marble always remains cooler than room temperature. Could someone explain if this is just a myth or fact?

2007-07-30 09:54:49 · 8 answers · asked by tad_pole99 1 in Physics

Solve the equation: -8.2n = -41

2007-07-30 09:54:48 · 4 answers · asked by mathmakesmecrazy 1 in Mathematics

Evaluate: -1.8 - 3.2 + 2.4

* if you could show me how you get to the answer that would help a lot thanks : )

2007-07-30 09:52:25 · 4 answers · asked by mathmakesmecrazy 1 in Mathematics

2007-07-30 09:48:59 · 6 answers · asked by Anonymous in Astronomy & Space

What would be necessary?

2007-07-30 09:48:47 · 18 answers · asked by deucegizzlo1 1 in Astronomy & Space

Is the radiation belt further out than the moon?

2007-07-30 09:47:42 · 8 answers · asked by mandy28227 1 in Astronomy & Space

in what state will you find yourself when you awake?

2007-07-30 09:43:34 · 2 answers · asked by Alexander 6 in Physics

1 mole of COCl2(g) was placed in a 500ml reaction flask. At equ'm the concentration of the product Cl2(g) was 0.7M. The other product is CO(g). Calculate K.

Please show your work! Thanks :D

2007-07-30 09:41:00 · 2 answers · asked by Mickey mouse 1 in Chemistry

Actually i cant undestand that how to do antilog operation on calculator or is tehre anyother way?
For example: [H3O+]= 10 (-7.3)pH
[H3O+]=5.01x10`-8 (-8 is the power) how they get that answer, i found this from books example.

2007-07-30 09:30:25 · 4 answers · asked by chem-mystry 2 in Chemistry

2007-07-30 09:30:01 · 24 answers · asked by Anonymous in Physics

People power?

Think about it. A job. You could like... Run around a huge hamster wheel or run on a treadmill-type-thing or something... I'm sure that would generate a lot of energy plus it would open more job opportunities... Right? Or is this just stupid?

2007-07-30 09:27:58 · 24 answers · asked by Anonymous in Engineering