Science & Mathematics - 17 December 2007

2007-12-17 09:14:31 · 5 answers · asked by Alexander 6 in Mathematics

We have had to build a roller coaster. Now we have to calculate force of friction but I do not know how. Here is the data that I have:

the acceleration of the ball on the initial drop= 6.4 m/s

the average speed of the drop= 1.67m/s

the average theoretical speed of drop = (speed without friction) = 1.73 m/s

theoretical instantaneous speed after drop( without friction)= 3.46 m/s

height of drop = 0.61 m

length (distance) of drop= 0.9 m

mass of marble = 5 g

2007-12-17 09:13:39 · 1 answers · asked by Caroline B 2 in Physics

2007-12-17 09:11:47 · 7 answers · asked by Anonymous in Mathematics

2007-12-17 09:11:14 · 2 answers · asked by Boogie 2 in Mathematics

2007-12-17 09:09:54 · 2 answers · asked by sajeev86 3 in Zoology

Find all of the elements k such that U(25) = . Not sure how to go about this one.

2007-12-17 09:09:40 · 1 answers · asked by Anonymous in Mathematics

1) Which of the following is the correct name for the acid HCN ?

a) cyanic acid
b) cyanous acid
c) hydrocyanous acid
d) hydrocyanic acid

2) If an acid does not contain oxygen, the name of the acid begins with which of the following prefixes?

a) anoxy-
b) peroxy-
c) hydro-
d) mono-


3) What is the name and formula for the anion corresponding to sulfuric acid, H2SO4?

a) SO4-, sulfate ion.
b) SO32-, sulfite ion.
c) SO32-, sulfate ion.
d) SO42-, sulfate ion.

4) The carbonate ion is CO32-. Which of the following is carbonic acid?

a) HCO3
b) H2CO3
c) H(CO3)2
d) HClO3

5) What is the name of the acid with the formula H3PO4?

a) perphosphoric acid
b) phosphoric acid
c) phosphorous acid
d) hypophosphorous acid

6) What is the name of the acid with the formula H3PO3?

a) perphosphoric acid
b) phosphoric acid
c) phosphorous acid
d) hypophosphorous acid

2007-12-17 09:08:54 · 4 answers · asked by :: 561 :: 1 in Chemistry

which of the following occurs during the alteration after translation?

excision of introns
excision of exons
addition of a poly (A) tail
formation of peptide bonds
proteins from a quaternary structure

2007-12-17 09:06:05 · 3 answers · asked by Lina A 1 in Biology

Vitamin bottles generally state on their lables the health benifits you get if you use the product. Every bottle of vitamins sold in the us has a message high lighted on the lable somewhere, by the food and drug administration. it reads....
" These statements have not been evaluated by the food and drug administration. This product is not intended to diagnose, treat, cure, or prevent any disease"
Vitamins have been on the shelves many decades now. Why hasen't the FDA evaluated these statements ? If they haven't evaluated them, then how did they come up with the warning that they're not intended to treat, cure, or diagnose disease. Also this message does not appear on any drug bottles. Why does the FDA refuse to evaluate these statements.

2007-12-17 09:03:54 · 5 answers · asked by Anonymous in Medicine

f(x)= x^3 - 5x^2 + 5x -1

2007-12-17 09:03:00 · 3 answers · asked by BabyG 1 in Mathematics

how does the geography in haiti affect how the people live?

please&&thanks

2007-12-17 09:02:40 · 4 answers · asked by Anonymous in Geography

2007-12-17 09:02:34 · 14 answers · asked by BRETT_DUNLOP 1 in Zoology

Describe clearly the similarities and differences in menopause for females compared to males. Thanks!!

2007-12-17 09:02:32 · 3 answers · asked by beeve.stroganoff 2 in Biology

2007-12-17 08:59:27 · 12 answers · asked by Anonymous in Engineering

The increased cooling that a wind can cause is called the__________.


Thanks for your help.

2007-12-17 08:56:52 · 2 answers · asked by kate 1 in Earth Sciences & Geology

Find the reflection of the point A(3,-2) through the mirror line of y=1/2x-1. Please show every step. Thanks!

2007-12-17 08:53:53 · 1 answers · asked by Tanda 2 in Mathematics

Given that m divides n, how do I find a homomorphism where phi(Z_n) = Z_m ? Please explain...

Please if you have no idea what a homomorphism is, keep your stupid comments to yourself!!!

2007-12-17 08:52:45 · 1 answers · asked by Jamanski 3 in Mathematics

Here are some serious flaws about Evolution.

1. According to the laws of nature and science that which is greater cannot come from that which is lesser. Therefore, it is more logical that existence will come from a Creator rather than for existence to come from an amoeba.

2. There are no transitory species which means we cannot find any species of animal in a halfway changing point. Nor can we find any species with even that potential to change.

3. DNA DeoxyriboNucleicAcid, every creature has the genetic code that God has given it, you cannot change your DNA. A cat cannot become a dog and a monkey cannot become a human.

Although a species may change, there is never an instance of one species becoming a totally other species altogether.

Any thoughts?

2007-12-17 08:49:30 · 21 answers · asked by Anonymous in Biology

Reviewing some questions for test prep, and stuck on this one:

Maximize - z = 5x1 + 3x2 + 7x3
Subject to: 4x1 + 3x2 + 2x3 < 60
3x1 + 4x2 + x3 < 24
x1 > 0, x2 > 0, x3 > 0

Please help, I stuck at linear programming!

2007-12-17 08:48:05 · 1 answers · asked by p_kubhakin1980 1 in Mathematics

Snow is white and I thought ice was clear.

2007-12-17 08:44:41 · 13 answers · asked by joey 2 in Weather

This problem is from the Prentice Hall Geometry book in p. 187.

Three red hats and three blue hats are packed in three boxes, with two hats to a box. There is a picture, which is that the 1st box has two red hats, the 2nd box has two blue hats and the 3rd box has one blue hat and one red hat. The boxes i just described are all labeled incorrectly. To determine what each box actually contains, you may select one hat from one box. Explain how this will allow you to determine the contents of each box. (Hint: List all possible solution; then use logic to solve.) FYI: This is for school

2007-12-17 08:41:59 · 1 answers · asked by Anonymous in Mathematics

Ok, so I was surfing in Maui last week, and I was just sitting on my surfboard waiting for a wave when I noticed a little prick on my leg. I raised my leg out of the water and saw this bug about the size of a grasshopper and it was blackish, I waived my leg around like a maniac and then the bug was gone and the pain settled in. I paddled to shore to take a look at it and there was a stinger about 1/3" long stuck in my leg - my leg had a 1/2" diameter spot that was raised/swoolen and a 2" diameter that was red. About a half hour after I pulled the stinger out, the swelling went down. My brother thought is was a jellyfish until he saw the stinger - someone else thought it was a sandfly, but they don't sting, just bite.

What could it have been - I'm not really worried, just curious...

2007-12-17 08:41:51 · 3 answers · asked by Anonymous in Zoology

Can Ar-40 change back to K-40? Explain your answer, pointing out what procedural part of the experiment supports your answer.

2007-12-17 08:41:36 · 3 answers · asked by Anonymous in Biology

2007-12-17 08:41:33 · 3 answers · asked by sherryyyyyy .A. 1 in Chemistry

match the following

1 nearly 200 F at noon a. temperate forest
2 cold winters:hot very dry windy summers b. desert
3 nearly -100 f at noon c grassland
4 below 0 in winter;hot summers d. rainforest
5 below zero in winter; warm summers (70 F) e taiga
6 continuous mild temp. year round f tundra

2007-12-17 08:39:14 · 2 answers · asked by devilgirl 2 in Earth Sciences & Geology

A beam has an angular velocity of 10 rad/s. After 40 revolutions its angular velocity has increased to 30 rad/s. Find angular acceleration. If the beam has a mass of 10 kg and a force of 10N acting on it. Find F1 which is located at the end of the 5 meter beam.

**I'm not sure if you have to convert rad/s to rev/s?

2007-12-17 08:38:17 · 1 answers · asked by Anonymous in Physics

A + B = C
A + D = B
2C = 3D
B > 0

2007-12-17 08:37:41 · 2 answers · asked by etweety419 1 in Mathematics

A tractor is pulling 2 cars through the mud. The magnitude of the resultant vector is 5000lbs along the x-axis. Find the tension in the tow lines if they make a 15 degree angle with the axis of the tractor. Thank-you in advance for the help i got a big test coming up and need to know this subject. it is my weakest one. thank-you

2007-12-17 08:37:26 · 2 answers · asked by Anonymous in Mathematics

I know quite a bit about space and light, however there is one thing that I have trouble with: How do we know if anything exists if it is so far away? Are we assuming things several million lightyears away still exist? (sorry if this sounds like an ignorant question to some people)

2007-12-17 08:36:55 · 19 answers · asked by luopjiggy 1 in Astronomy & Space

Comparing Accelerations
How does the acceleration of an object traveling eastward slowing down at a rate of 5 m/s2 compare to the acceleration of a second object traveling westward speeding up at a rate of 5 m/s2?

and


At the top of a hill, a rollercoaster is traveling with a velocity of 2.0 m/s downward, but accelerates to 15.0 m/s by the time it reaches the bottom of the hill. If it took 2.0 seconds to reach the bottom of the hill, what was its acceleration?

and

What is the final velocity of an object starting from rest which accelerates at 17.0 m/s2 northward for 3.0 seconds?

2007-12-17 08:36:16 · 1 answers · asked by rayray 1 in Mathematics