Science & Mathematics - 14 October 2006

I kind of know how to start it off:

The Inverse Trig. Function for cos^-1 is -1/ sq root (1-x^2).

So it would be [-1/ sq root(1-cos^2(x))] * d/dx cos(x). d/dx cos(x) is equal to -sin(x).

So then you would have sin(x)/ sq root(1-cos^2(x)).

First off, am I right. Second, isn't my answer an identity?

2006-10-14 21:45:42 · 3 answers · asked by burkehud 2 in Mathematics

The next evolution of humans???
Impact from some other object from space???
Alien invasion (for those that believe)???
Major disease epidemic???
War (possibly nuclear)???
or Other???

2006-10-14 21:44:14 · 27 answers · asked by Forlorn Hope 7 in Other - Science

person who gives me the answer to this question---> 10 points fo u!
(i mean pleaze. im desperate.)

2006-10-14 21:44:01 · 2 answers · asked by sudha 2 in Geography

http://www.pbs.org/wnet/nature/excats/homing.html

Do cats have a reliable homing instinct. Or are they too selfish and independent to be of any use?

2006-10-14 21:38:18 · 21 answers · asked by Perseus 3 in Zoology

I'm prepping for my A2 Physics practical to be held in 4 days' time. I was wondering what's the simplest way to draw effective arrangements of:

(i) a hall probe (e.g. do i just draw two wires protruding from a cylinder shape - probe - connected in series to a 'datalogger' and in parallel to a power supply? or are more wires needed?)

(ii) double light gates (how many wires do i need? where do they go?)

(iii) Geiger-Muller tube (how many wires needed and what to use to determine count rate)

(iv) platinum resistance thermometer and thermocouple thermometer (how would i draw the shapes of them? are they attached to probes? what are they connected to?)

help with any of the above will be much appreciated!

2006-10-14 21:36:37 · 2 answers · asked by Ray M 1 in Physics

plz and thx

2006-10-14 21:33:43 · 13 answers · asked by kh2anime 1 in Physics

2006-10-14 21:33:14 · 4 answers · asked by Anonymous in Physics

Alvin's age is five times as Ralph's. If 10 is added to Ralph and 10 is subtracted from Alvin, their ages will then be equal. How old is each now?

2006-10-14 21:27:27 · 12 answers · asked by double B 2 in Mathematics

Tell me the details of snowstorm!!!!
QUICK!
QUICK!
QUICK!


PLEASE!~!~!~

2006-10-14 21:21:09 · 23 answers · asked by 偌瑤 1 in Weather

You throw a rock of weight 21.0 vertically into the air from ground level. You observe that when it is a height 14.9 above the ground, it is traveling at a speed of 25.6 upward.
Part A
Use the work-energy theorem to find its speed just as it left the ground;
Take the free fall acceleration to be = 9.80 .
m/s





Part B
Use the work-energy theorem to find its maximum height.
Take the free fall acceleration to be = 9.80 .

2006-10-14 21:17:18 · 2 answers · asked by googoosh g 1 in Physics

You are asked to design spring bumpers for the walls of a parking garage. A freely rolling 1300 car moving at 0.600 is to compress the spring no more than 7.40×10−2 before stopping.
What should be the force constant of the spring? Assume that the spring has negligible mass.

2006-10-14 21:15:04 · 1 answers · asked by googoosh g 1 in Physics

2006-10-14 21:12:05 · 5 answers · asked by Anonymous in Biology

About 300,000,000 years ago, some insects were much larger during the late Paleozoic period because Earth's air had an oxygen content of 35%, as compared to 21% during the present age. Dragon flies, for example, had a wingspan of two and one-half feet. How would you like THEM buzzing your picnic table?

2006-10-14 21:11:04 · 4 answers · asked by In Honor of Moja 4 in Zoology

2006-10-14 20:58:52 · 16 answers · asked by michael b 5 in Weather

2006-10-14 20:57:51 · 6 answers · asked by lomna 1 in Physics

Solve each of the following systems of linear equations.
(a)

5x - y = 11
3x + 2y = 4

(b)
3x + y = 2
y = -3x -5

2006-10-14 20:57:04 · 6 answers · asked by Agentj100 4 in Mathematics

2006-10-14 20:56:44 · 4 answers · asked by lomna 1 in Physics

Can electro magnetic waves (including photons) be sent back in time ?

2006-10-14 20:56:06 · 5 answers · asked by rajesh bhowmick 2 in Physics

2006-10-14 20:48:22 · 8 answers · asked by daisuke_azalie 1 in Other - Science

2006-10-14 20:48:16 · 1 answers · asked by pornstar_rockrules 1 in Physics

are fallen angels real or fiction ?

2006-10-14 20:42:34 · 14 answers · asked by sammy199_&& 1 in Astronomy & Space

Could you send me a link or a file about industrial valves please?

2006-10-14 20:32:46 · 3 answers · asked by Anonymous in Engineering

2006-10-14 20:29:34 · 11 answers · asked by sachin 1 in Earth Sciences & Geology

solid, liquid, gas or plasma???

2006-10-14 20:22:58 · 10 answers · asked by rishi 1 in Chemistry

2006-10-14 20:16:43 · 53 answers · asked by Ahmed M 2 in Mathematics

Kansas City and Denver are 600 miles apart. Two cars start from these cities, traveling toward each other. They meet after 6 hr. Find the rate or each car is one travels 30 miles slower than the other?

2006-10-14 20:13:24 · 6 answers · asked by LW 1 in Mathematics

Suppose a system"A" is there whose axis is having "+n" points on its axis & another system "B" identical to system "A" is there on the opposite side of system "A" but apart from system "A" having same "+n" points on its axis.Then there would be an axis joining "+n" of system "A" & "+n" of system "B".What would be the center of such an axis joining "+n" of system "A" & system "B"?
Take "+n" as +1.

2006-10-14 20:12:13 · 1 answers · asked by rajesh bhowmick 2 in Mathematics

What is the name of France's highest mountain?
a.Charles VIII
b.Napoleon III
c.Charles IV
d.Napoléon I

2006-10-14 20:10:50 · 5 answers · asked by ankit g 1 in Geography

2006-10-14 20:10:04 · 3 answers · asked by Jess C 1 in Other - Science

For large bodies which cannot be weighed on one single weighing machine,then how to calculate the correct weight with multiple machines under each support?

2006-10-14 20:09:59 · 3 answers · asked by sehjra 1 in Physics