Science & Mathematics - 20 September 2006

2006-09-20 10:38:20 · 7 answers · asked by keith321a 1 in Geography

2006-09-20 10:37:17 · 6 answers · asked by Ali 2 in Other - Science

How do I find tan theta=.6873 in quadrant III? I need to round my answer to the nearest tenth of a degree

2006-09-20 10:36:15 · 3 answers · asked by yeppperz 1 in Mathematics

SERIOUS ANSWERS ONLY

Thanks!

2006-09-20 10:34:28 · 2 answers · asked by c90 4 in Chemistry

(i) Show that x^3 - (1+cos@ + sin@) x^2 + (cos@sin@ + cos@ + sin@)x - sin@cos@ = (x-1)(x^2 - (cos@ + sin@)x + cos@sin@)
and deduce that the cubic has roots 1, cos@, sin@

(ii) Give the roots when @ = pi/3

(iii) Find all values of @ in the range 0 <=@<2pi such that two of the three roots are equal

(iv) What is the greatest possible difference between two of the roots, and for what values of @ in the range 0<=@<2pi does this greatest difference occur?

2006-09-20 10:34:00 · 3 answers · asked by Math_Guru 2 in Mathematics

Sc(CrO4)3
Mg(NO2)2


It has been awhile since I've done this stuff. Help me out ;)

2006-09-20 10:32:34 · 6 answers · asked by Anonymous in Chemistry

i need to no for class plz help me!!!!!

2006-09-20 10:29:53 · 13 answers · asked by Anonymous in Earth Sciences & Geology

how do you factor and how do you find the zeros of:
x^3 - 3x^2

would i need to fill in the missing places, i.e. x^3-3x^2+0x+0 ?
thanks for your help.

2006-09-20 10:29:43 · 7 answers · asked by shih rips 6 in Mathematics

this is a hw question. 10 pts to the right answer

Plate Tectonics Worksheet:

What often happens at the boundaries of the plates? Are these internal or external forces?

explain please

2006-09-20 10:28:27 · 6 answers · asked by Anonymous in Earth Sciences & Geology

2006-09-20 10:26:12 · 7 answers · asked by sharank105 1 in Other - Science

2006-09-20 10:25:44 · 20 answers · asked by Alicat 6 in Biology

I have a test 2morrow and I am having problems with the wording of this practice problem... can someone please explain and or walk me through it...

What peak to peak sinusoidal voltage must be connected to a half wave rectifier if the rectified wave form is to have a dc value of 6 V ? Assume that the forward drop across the diode os 0.7 V.

Am I looking for Vpr (peak value of rectified waveform), or Vpp (peak to peak voltage)... Do i have to do anything with Vrms? I am so confused

2006-09-20 10:24:51 · 7 answers · asked by Oo 2 in Engineering

In 1895 J. C. Bose gave his first public demonstration of electromagnetic waves, using them to ring a bell remotely and to explode some gunpowder. In 1896 the Daily Chronicle of England reported: "The inventor (J.C. Bose) has transmitted signals to a distance of nearly a mile and herein lies the first and obvious and exceedingly valuable application of this new theoretical marvel." Popov in Russia was doing similar experiments, but had written in December 1895 that he was still entertaining the hope of remote signalling with radio waves. The first successful wireless signalling experiment by Marconi on Salisbury Plain in England was not until May 1897.

http://www.tuc.nrao.edu/~demerson/bose/bose.html

2006-09-20 10:23:44 · 8 answers · asked by Anonymous in Engineering

both use lenses, right?

2006-09-20 10:22:49 · 3 answers · asked by this isnt my name. 1 in Other - Science

2006-09-20 10:22:38 · 12 answers · asked by Navita 3 in Other - Science

2006-09-20 10:21:57 · 3 answers · asked by AnswerBlaster 2 in Biology

2006-09-20 10:20:46 · 10 answers · asked by Navita 3 in Other - Science

i need a map!!!!!

2006-09-20 10:19:05 · 8 answers · asked by camila <3 3 in Other - Science

2006-09-20 10:18:36 · 5 answers · asked by Anonymous in Mathematics

i've noticed up to 5 pounds difference before and after a bath

2006-09-20 10:18:17 · 20 answers · asked by Anonymous in Biology

2006-09-20 10:17:51 · 8 answers · asked by Navita 3 in Other - Science

Why does the Shuttle roll after take off (it rolls about 100 degrees or so just after clearing the tower). Why does it do this - and what would happen if it didn't? Thanks.

2006-09-20 10:16:15 · 9 answers · asked by paulmurphy42 1 in Astronomy & Space

So im determining the amount of Na2CO3 in a sample of soda ash by titrating it with HCl. I need help coming up with the equations. This is what I know:
The reaction occurs in 2 stages the first titration with one indicator and the second titration with another indicator. Theres supposedly 6 equations including the complete and net ionic equations...I know that the final equation would be this:

Na2CO3 + HCl = H20 + NaCl + CO2
because the H2CO3 is not stable or w/e so it changes to CO2. I need help coming up with the other different equations for each stage I started with stage 1 and tried this:
Na2CO3 + HCl = NaCl + NaHCO3
but i dont know if thats correct and i dont know where to progress from there to stage 2. Please help! Thanx!

2006-09-20 10:13:37 · 1 answers · asked by swejedi7 1 in Chemistry

A swan on a lake gets airbourne by flapping its wings and running on top of water. (a) if the swan must reach a velocity of 6.00 m/s to take off and it accelerates from rest at an avg. rate of 0.350m/s^2, how far will it travel before coming airbourne? (b) How long does it take?

2006-09-20 10:13:20 · 4 answers · asked by cheertee1126 1 in Physics

I have read that it has to do with larva, but my jumping beans are several years old and jump when put under a light. However, they only jump when the clear plastic case around them is closed. So how do these beans jump?

2006-09-20 10:13:03 · 9 answers · asked by Anonymous in Other - Science

Please

2006-09-20 10:11:41 · 10 answers · asked by Chuck B 2 in Earth Sciences & Geology

2006-09-20 10:06:43 · 3 answers · asked by nani_nela 1 in Chemistry

2006-09-20 10:05:02 · 4 answers · asked by Anonymous in Mathematics

A few books I have read about medieval times suggest putting raw meat (generallt red meat) over a bruise to help it heal. It is generally on the face. I was wondering whether there was a scientific reason or whether it was just to reduce the swelling as they didn't have frozen peas in those days. Something to do with zinc or iron in the meat perhaps? It's just I thought they salted meat to preserve it as they had no cooling devices.

2006-09-20 10:04:42 · 8 answers · asked by bushgirl2cool 1 in Medicine

it is part of my haomework an di need help

2006-09-20 10:04:27 · 8 answers · asked by kymberlee 1 in Mathematics