Science & Mathematics - 31 October 2007

2007-10-31 13:50:01 · 5 answers · asked by Anonymous in Zoology

not just your normal large house variety, not just the smaller half-size ones... but also these TINY tiny 1/5 length of a grain of rice miniscule ones that live near my bed, that could easily crawl into my nose or ear when I'm sleeping.

What can I do??

2007-10-31 13:49:10 · 4 answers · asked by Anonymous in Zoology

Ok so I've heard prolly 10 different reasons why ppl think the world will end in 2012. But my question is....whats the hype? I mean why do ppl think that an alignment of the center of the galaxy and our sun would end anything! It makes no sence and just doesn't add up!

2007-10-31 13:48:00 · 13 answers · asked by Lorah 2 in Astronomy & Space

basically i am given an invasive species (african giant snails..they were imported to hawaii)
can any one please give me a ROUGH idea of how the following experiment could possibly be cairried out please?
how can you tEST a hypothesis (not in real life though..only for school...) that this species truly is invasive ? any CREATIVE, original brilliant ideas would be so greatly appreciated, you have no clue!!
thanks!!

2007-10-31 13:47:59 · 1 answers · asked by Anonymous in Zoology

In a mixture of Ne and H2 gases, the partial pressure of Ne is 0.150 atm. The total pressure is 0.405 atm. The temperature is 36.0oC. If the total volume of the gas mixture is 433 mL, what is the mass of H2 in grams?

2007-10-31 13:45:57 · 3 answers · asked by Anonymous in Chemistry

Fairgoers ride a Ferris wheel with a radius of 6.00 m (Figure 4-18), the bottom of which is 1.75 m above the ground. The wheel completes one revolution every 28.0 s.

Figure 4-18


(b) If a rider accidentally drops a stuffed animal at the top of the wheel, where does it land relative to the base of the ride? (Neglect air resistance.)
m

2007-10-31 13:45:40 · 2 answers · asked by Chris B 1 in Physics

A player passes a 0.6 kg basketball downcourt for a fast break. The ball leaves the player's hands with a speed of 7 m/s and slows down to 4.9 m/s at its highest point.

How high (above the release point) is the ball when it is at its maximum height?

2007-10-31 13:38:45 · 1 answers · asked by =P 6 in Physics

I’m stuck on some problems for a lab report. Here are the questions, and my thinking on them so far:

A) Each of the following samples contains only one of the two chemicals indicated. What reagent would you use to identify which of the chemicals is present that you would use to distinguish between the two chemicals? Explain your choice.

1) Na2SO4 and NaI (Reagent: BaCl3 or FeCl3)

Leaning towards BaCl3, because it produces a precipitate with NaI only.

2) Fe(NO3)3 and Zn(NO3)2 (Reagent: NH3 or K4[Fe(CN)6])

NH3, because the other introduces Fe whether or not it is already present?

3) K3PO4 and Na2CO3 (Reagent: (NH4)2MoO4 or HCl)

I’m at a loss for this one.

B) How would you go about testing for the presence of SO4 in the presence of NO3?

Add a base first, or something else to react with the NO3 before you add the BaCl2, so that the Ba isn’t all used up in the formation of soluble barium nitrate. Maybe just excess BaCl2?

Tips and/or answers greatly appreciated!

2007-10-31 13:37:09 · 2 answers · asked by Anonymous in Chemistry

What is the wavelength in meters of the photon emitted when this highly excited hydrogen atom of hydrogen makes its transition from the n = 9 to the n = 8 state?

2007-10-31 13:36:29 · 1 answers · asked by Anonymous in Chemistry

The bright-red color of highway safety flares comes from strontium ions in salts such as Sr(NO3)2 and SrCO3. Burning a flare produces strontium ions in excited states, which then emit red photons at 606 nm and several wavelengths between 636 and 688 nm. Calculate the energy (in Joules per mole) of the 684-nm emission.

2007-10-31 13:35:40 · 1 answers · asked by Anonymous in Chemistry

Im looking for a telescope for my dad.
I dont want it to be too expensive but i want a really good one.
Thank You !

2007-10-31 13:33:02 · 5 answers · asked by Anonymous in Astronomy & Space

2007-10-31 13:31:11 · 1 answers · asked by mr. murf 1 in Weather

2007-10-31 13:30:06 · 15 answers · asked by benedict n 1 in Botany

2007-10-31 13:27:01 · 1 answers · asked by John S 1 in Chemistry

2007-10-31 13:26:26 · 3 answers · asked by Q 1 in Mathematics

v^2 = u^2 + 2as ?

This formula is used for what? I was looking through the book just now when I came across this formula that I have never seen before...Please help me by telling how to use this formula and when to use this formula...What's impt is that you can tell me how do you derive this formula cos I HAVE NEVER SEEN IT BEFORE? Thanks

2007-10-31 13:19:19 · 1 answers · asked by Anonymous in Physics

So apparently that's why the Mayan Calandar stop on Dec 21, 2012, cause because of a polar shift, they can no longer make the calculation.

At this date, the earth and sun, will be in a perfect alignement with the center of our galaxy (something happening only once every 26000 years).

Apparently this will cause major problem with our planet, a possible polar shift. Do you believe in that ? It has been proven that earth poles shift on several occasions before and they will do it again.

2007-10-31 13:15:55 · 16 answers · asked by Kaynos 5 in Astronomy & Space

Writ an equation of a parabola with the given focus and directrix.

2007-10-31 13:15:39 · 1 answers · asked by Anonymous in Mathematics

Please provide explanation. My guess 1/-0.4 but I think only integers count as fractions?

2007-10-31 13:15:28 · 3 answers · asked by Selene 1 in Mathematics

2007-10-31 13:14:45 · 2 answers · asked by Anonymous in Physics

A machine is rolling a metal cylinder under pressure. The radius of the cylinder is decreasing at a constant rate of 0.05 inches per second and the volume V is 128pi cubic inches. At what rate ios the length h changing when the radius r is 2.5 inches? [hint: V = pi(r^2)h]

please explain the problem. just an answer wont help

2007-10-31 13:14:42 · 4 answers · asked by NEEDSHELP 1 in Mathematics

I've made a lot of changes and have avoided old friends who I had nothing in common with anymore.. Its Halloween and I'm feeling kinda lonely cuz I'm not doing anything.. can you give me advice

obviously I'm asing psychics

2007-10-31 13:13:39 · 15 answers · asked by Anonymous in Paranormal Phenomena

what is the answer? im just testing someting, its an expiriment

2007-10-31 13:13:30 · 2 answers · asked by Jamie K 1 in Mathematics

4 + 4 = ,6 x 6 = ,12 + 12 = ,24 x 24 = ,48 + 48 = ,96 x 96 = .

2007-10-31 13:09:50 · 10 answers · asked by Simon 3 in Mathematics

math

2007-10-31 13:06:45 · 5 answers · asked by Shannon R 1 in Mathematics

Read my question carefully because it's difficult to explain. I'm in the northern hemisphere (about 35 degrees north lattitude). Late in the evening (Halloween) I saw the moon was up about 45 degrees. It's a half moon. What's weird is that the line between the dark half (top) and the light half (bottom) wasn't parallel to Earth's horizon. I would expect the sun to be south to the equator so the line through the moon would go from the top right (left is Earth's north) to the bottom left. Instead, it was the other way as if the sun was even farther north than I am. Why is that?

2007-10-31 13:06:31 · 2 answers · asked by Anonymous in Astronomy & Space

2007-10-31 13:05:48 · 18 answers · asked by Anonymous in Earth Sciences & Geology

If you have a semi-circle, which the flat side is 50cm, what is the area of the smallest possible square which the semi-circle will fit into? I got 1250cm, but feel as this is wrong. Any help?

2007-10-31 13:05:38 · 6 answers · asked by glassharlequin 2 in Mathematics

A projectile is fired horizontally from a gun that is 41.0 m above flat ground, emerging from the gun with a speed of 250 m/s.
It remains in the air for 2.9 seconds.

1.) At what horizontal distance from the firing point does it strike the ground? (m)

2.) What is the magnitude of the vertical component of its velocity as it strikes the ground? (m/s)

2007-10-31 12:59:42 · 3 answers · asked by Chaz 3 in Physics

Since the human brain is so big - sometimes causing female pelvics to break - wouldn`t natural selection work against humans evolving to have bigger brains?

BTW - I`m an atheist that does not deny that evolution is a fact. This question is merely a gap in my understanding - it is not some creationists attempt to prove the theory wrong.

2007-10-31 12:57:57 · 8 answers · asked by Future 5 in Biology