Science & Mathematics - 24 September 2006

2006-09-24 08:47:35 · 5 answers · asked by khan94@sbcglobal.net 1 in Other - Science

I've read in a book that sounds are heard more clearly at nights and it was because of total internal reflection of waves going up.But I think the explanation is wrong because sound travels faster in denser medium than in rarerr medium.Please explain.

2006-09-24 08:44:01 · 12 answers · asked by pavan 1 in Physics

if it was possible how long would it take from one point on earth to walk foward and reach the same point?

2006-09-24 08:43:27 · 3 answers · asked by Arroyo R 1 in Physics

Could somebody explain me the Mendelian laws...with examples, and also, linkage group

2006-09-24 08:42:53 · 1 answers · asked by ABC 4 in Biology

2006-09-24 08:42:06 · 2 answers · asked by fajrmuhammad 1 in Earth Sciences & Geology

I have a 30 unit insilin syringe and need to administer 272 mcg

2006-09-24 08:42:05 · 2 answers · asked by Dobergirl 1 in Medicine

Have there been any studies of radiation from wireless routers hurting animals? I know EMFs can slow reproduction rates, and cell phones cause brain scarring. I'm doing a science fair project to see how it affects Planaria's regeneration, so any information would be a huge help. Thanks! (-=

2006-09-24 08:40:57 · 7 answers · asked by Anonymous 2 in Biology

if a tree falls in the middle of a rainforest, does it make a sound?

2006-09-24 08:38:53 · 10 answers · asked by Anonymous in Earth Sciences & Geology

2006-09-24 08:33:01 · 7 answers · asked by Anonymous in Biology

2006-09-24 08:31:22 · 6 answers · asked by poetic_lala 5 in Mathematics

just wanting to know if it is wise to run around during a snowstorm

2006-09-24 08:29:07 · 16 answers · asked by daniel.gzmn 2 in Weather

Your Professor is tired of having to use 9.8m/s^2 all the time to do his calculations concerning gravity. He wants to use a nice round number 10 m/s^2. How much mass would have to be added to the Earth to make this happen? What would the new radius of the Earth be? Assume that the density of the Earth will remain the same. Where could you get the mass needed?

2006-09-24 08:28:44 · 5 answers · asked by Shane W 1 in Physics

2006-09-24 08:26:59 · 2 answers · asked by maz 2 in Biology

Ok, here's the problem...

"The specific heat capacity of ice is about 0.5cal/g x degrees celsius. Supposing that it remains at that value all the way to absolute zero, calculate the number of calories it would take to change a 1-gram ice cube at absolute zero (-273 degrees celsius) to 1 gram of boiling water. How does this number of calories compare with the number of calories required to change the same gram of 100 degree celsius water to 100 degrees celsius steam?"

I've stared at this problem for a while, and I have no idea where to even start. Am i supposed to use the formula Q = mcDT? I have no idea! Please help!

2006-09-24 08:26:28 · 5 answers · asked by Anonymous in Physics

i need some ideas on the scientific method...

2006-09-24 08:26:13 · 1 answers · asked by Anonymous in Other - Science

I can't figure out how to get the answer for this constant of proportionality. HELP !!!

2006-09-24 08:23:42 · 1 answers · asked by heather d 2 in Mathematics

Any explanations? I did save it.

2006-09-24 08:21:51 · 8 answers · asked by MaximumFunds4US@aol.com 2 in Zoology

HCl(aq) + NaOH(aq) ---> NaCl(aq) + H20(l)
CH4(g) + 2O2(g) ---> CO2(g) + 2H20(g)
2Na(s) + 2 H20(l) ---> 2 NaOH(aq) + H2(g)
Zn(s) + MnO2(s) +H2O(l) ---> Zn(OH)2 (s) + Mn2 O3 (s)

2006-09-24 08:21:51 · 3 answers · asked by ChaseMakesMeSmile 2 in Chemistry

What is the charge of a neon ion?

2006-09-24 08:17:35 · 4 answers · asked by Anonymous in Chemistry

help with this problem please...a spherical raindrop evaporates at a rate proportional to its surfacce area. write a differential equation for the volume of the raindrop as a function of time?

2006-09-24 08:16:11 · 2 answers · asked by Anonymous in Mathematics

The 2 vectors 3i-7j (no k) and 2i+3j-2k define a plane (its the plane of the triangle with both tails at one vertex and each head at one of the other vertices).
Which of the following vectors is perpendicular to the plane?
a 4i+6j+13k
b -4i+6j+13k
c 4i-6j+13k
d 4i+6j-13k
e 4i+6j

I did the cross product and got
=i(AyBk-AkBy)+j(AkBx-AxBk)+k(A...
=14i+6j+23k

How do I go from here?

2006-09-24 08:15:50 · 3 answers · asked by dutchess 2 in Physics

When magnesium metal is burned in air, two different products are made. One is magnesium oxide and the other is magnesium nitride. What are the formulas of these two compounds? What type of bonding exists in each.

2006-09-24 08:15:43 · 3 answers · asked by Anonymous in Chemistry

im a chaos girl myself

2006-09-24 08:13:36 · 7 answers · asked by Anonymous in Other - Science

Why can't scietists alter the genetic make-up of a dog's DNA to make they're aging process the same speed as it's human owner? I have a 13 year old dog and I I've accepted the fact that she may not be around for Christmas coz she has Congenitive Heart Failure. Dogs are man's best friend so why can't we help them live longer. I have a younger dog and I'm starting to regret getting her coz I know that I'll go through the same thing a few years from now when she's old too.

2006-09-24 08:10:19 · 14 answers · asked by blued79 3 in Biology

2006-09-24 08:06:41 · 5 answers · asked by Anonymous in Chemistry

1. An object weighs 45g its denisty is 12.9g/cm. When measured its height is 7.43 cm and width is 3.45. How long is the object?

2. Solid sodium chloride has a denisty of 2.16g/cm/ A chemist needs 56.1 mL of sodium chloride. How many grams should the chemist use?

2006-09-24 08:03:50 · 3 answers · asked by Anonymous in Chemistry

2006-09-24 08:02:13 · 5 answers · asked by aganjegelaga 1 in Biology

How can you get 2 x 5 - 1/2 x 10 x 9 to equal 45? If it can, can you tell me how and show me all the work? Thank you.

2006-09-24 07:59:25 · 7 answers · asked by Jae 2 in Mathematics

2006-09-24 07:57:55 · 19 answers · asked by snowpatrol161 2 in Biology

Write a recursive formula for each sequence. Use U0 for the first term given...

0, 20, 36, 48.8,....

2006-09-24 07:57:42 · 2 answers · asked by Anonymous in Mathematics