Science & Mathematics - 12 November 2007

A pendulum clock with a brass suspension
system is calibrated so that its period is 1 s at 13C.
If the temperature increases to 39C, by
how much does the period change in units of s?

How much time does the clock gain or lose in
one week in units of s?

2007-11-12 14:27:44 · 1 answers · asked by ? 1 in Physics

Let f be a differentiable function and define f2(x)= f(f(x)), f3(x)= f(f(f(x))) and so on. Find the expression for the derivative of fn(x), where n is any integer greater than or equal to 2.

I don't understand how to put this in terms of n! Please help!

2007-11-12 14:27:16 · 1 answers · asked by Jess 2 in Mathematics

This is a tough one. I'm expecting some quality answers here.

2007-11-12 14:25:54 · 8 answers · asked by rpevanic 1 in Other - Science

A specimen of aluminum having a rectangular cross section 10mm x 12.7mm (.4in x .5in.) is pulled in tension with 35,500N (8000 lbs) force, producing only elastic deformation. Calculate the resulting strain.

Note: i've done stress problems but not strain..please help.

2007-11-12 14:25:18 · 2 answers · asked by twiztid642 1 in Engineering

Look at the following list of environmental concerns and answer the 3 questions below (this is a survey):

a) Global Warming (part of "Climate Change")
b) Rising sea-levels (part of "Climate Change")
c) Modern Ice Age
d) Greenhouse Effect
e) Coral Reef Bleaching
f) Animal Extinction (i.e. Panda bears)
g) Depletion of Fossil Fuels (part of "Climate Change")
h) Land pollution (i.e. toxic waste dumps facilities)
i) Air pollution (burning fossil fuels)
j) Overpopulation
k) Water pollution (drinking water, ocean oil spills, etc.)

1.) Among the list, which ones interest you most? (pick AT LEAST one).

2.) Which one do you believe is important? (this can be a different answer from Q.1).

3.) Any other environmental concerns that is not listed on here that you think is of importance / interest?

2007-11-12 14:22:48 · 7 answers · asked by ♣ ♦ ♥ ♠ 3 in Earth Sciences & Geology

2007-11-12 14:21:38 · 16 answers · asked by RICK 1 in Astronomy & Space

I need to find the thinkness of a 35cm squared peice of aluminum that weighs 1.00grams.

Aluminum has a density of 2.7grams/cm cubed

2007-11-12 14:19:16 · 1 answers · asked by Anonymous in Chemistry

The distance traveled by a 75 mph train in 2 hours is 150 miles.
Compare each question with the information above.
a) Begining at a standstill, a car maintains a constant acceleration of 10 ft/sec^2 for 10seconds. What is its velocity after 10seconds? Give your answer in ft/sec and then convert in to mi/h.
b) In a vacuum, light travels at a speed of 300,000 kilometers per second. How many kilometers does it travel in a year? (This distance equals one light-year.)
c) A long distance runner ran in 5 hours, avering 6 mph for the first 3 hours and 5 mph for the last 2 hours. How far did she run?
This is a calculus problem. Please explain the answer in detail if you can.
This is a calculus problem.
I have answers, but I don't know how to get those answers.
(a) 100 ft/sec = 68.08mph
(b) 9.46*10^12 km
(c) 28 miles

2007-11-12 14:16:30 · 1 answers · asked by Anonymous in Mathematics

A searchlgith on a ship 1km from shore casts a spot of lgiht on the shore line. The searchlight is rotating at a rate of 1 rpm. How fast is the spot on the shore mvoing at the point nearest the searchlight? How fast is ti moving when the spot is 250 m father down the shore?

(i'm allowed to use the TI-83 after finding the equation for the answers...)
plz show me how u got the answers plz!!! beggin ya

2007-11-12 14:11:59 · 2 answers · asked by SDGD 1 in Mathematics

2007-11-12 14:10:49 · 7 answers · asked by Anonymous in Geography

I need this for a chem paper. Answer asap would be greatly appreciated!

2007-11-12 14:07:15 · 1 answers · asked by vikingboy1927 2 in Chemistry

The distance traveled by a 75 mph train in 2 hours is 150 miles.
Compare each question with the information above.
a) Begining at a standstill, a car maintains a constant acceleration of 10 ft/sec^2 for 10seconds. What is its velocity after 10seconds? Give your answer in ft/sec and then convert in to mi/h.
b) In a vacuum, light travels at a speed of 300,000 kilometers per second. How many kilometers does it travel in a year? (This distance equals one light-year.)
c) A long distance runner ran in 5 hours, avering 6 mph for the first 3 hours and 5 mph for the last 2 hours. How far did she run?
This is a calculus problem. Please explain the answer in detail if you can.
This is a calculus problem.

2007-11-12 14:03:16 · 1 answers · asked by Anonymous in Mathematics

I'm having problems with all these weird products in Chem problems. I don't see how I could have predicted these. Can someone explain the logic behind these to me. Here are a few examples.

Pure phosphorous burned in air.
P + O2 yields P4O10
Why?

Access concentrated HCl is added to 1.0M solution of CoCl2.
HCl + CoCl2 yields H2 + CoCl3
What the %^#^!?

Solid cesium oxide is added to water.
Cs2O + H2O yields 2Cs + 2OH-
Huh?

A solution of potassium hydroxide is added to solid ammonium chloride.
I don't even know about this one.

And what's up with sulfuric acid?
H2SO4 + anything yields whatever it wants apparently.

I seriously need help.

2007-11-12 14:02:05 · 2 answers · asked by Chris H 1 in Chemistry

what are the similarities and differences ? would be very helpful.. thank you!

2007-11-12 14:01:42 · 4 answers · asked by Anonymous in Earth Sciences & Geology

I have a question for science....I've looked on google, ask.com, everything I can think of...

Does anyone know the answer to this?

It's due Thursday...

2007-11-12 13:59:16 · 7 answers · asked by Anonymous in Earth Sciences & Geology

In a lab we need to separate 3 substances so they come out separtely. The three substances are
1. Salt
2. Sand
3. Iron Fillings

how can i separate these three substances so that all three come out in three diferent piles of differnet substances.

if you dont understand contact me at samusai12@gmail.com

PLZ DONT SEND ME SPAM!!

2007-11-12 13:53:54 · 10 answers · asked by KoolDude574 1 in Chemistry

1.5v-6.5w=3.5
0.5v+2w=3

what am i suppose to do?

2007-11-12 13:53:43 · 5 answers · asked by Anonymous in Mathematics

Give the maximum number of electrons in an atom that can have these quantum numbers.
n = 4, l = 0, m = 0

2007-11-12 13:53:03 · 2 answers · asked by Somerandomguy 1 in Chemistry

How can we find the Fourier Series for f(x) = x^3 without intergrating to find the coefficients, if it is known that f(x) = f(x + 2pi) = x^4 , -pi < x < pi, is (pi^4)/5 + 8pi^2(Sum from 1 to Infinity of: [(-1)^n/(n^2)] cos nx) - 48 (Sum from 1 to Infinity of: [(-1)^n/(n^4)] cos nx)?

2007-11-12 13:52:14 · 1 answers · asked by Jake Tenzel 1 in Mathematics

I'm wondering how they survive year to year

2007-11-12 13:51:28 · 4 answers · asked by Michael N 1 in Zoology

What I mean is, would it be possible to have two planets occupying the same orbit around the sun, and rotating around each other? Kind of like Earth and the moon, only it would be another planet in the moon's place, the same size as Earth.

2007-11-12 13:48:41 · 8 answers · asked by Antique Silver Buttons 5 in Astronomy & Space

You obtain a mean force reading of 2.33 N pulling on an object with a force sensor. During this time the object moves with uniform motion. Then you suspend the object from the hook of the sensor and obtain a reading of 12.2 N. Assuming the force sensor was properly zeroed, what is the coefficient of kinetic friction between the object and the surface?

2007-11-12 13:48:31 · 2 answers · asked by Hades Lee 2 in Physics

2007-11-12 13:48:01 · 2 answers · asked by nickie 2 in Earth Sciences & Geology

if not God?

2007-11-12 13:46:48 · 5 answers · asked by Jackie 2 in Astronomy & Space

Well i am back for some more questions.
I figured out that there is a relationship between mass and volume only when the density(object) is the same.

So now, in my experiment i have to use sample aluminum.
It is just like a round water droplet and NOT the log cylindrical samples.

Ok so my question is:

Lets say i start out with 5 samples i record the data. THEN i add 5 more samples. Record the data. And so on. Will this still show that there is a realtionship between mass and volume. A proportional relatiosnhiop?

2007-11-12 13:45:37 · 2 answers · asked by Anonymous in Physics

I am having trouble finding the physical and chemical properties of Calcium, especially because I dont understand a lot of what I am reading. Could someone please help me out with this?

Thanks soo much. :)

2007-11-12 13:43:00 · 3 answers · asked by Anonymous in Chemistry

Explain everything please!!!??

2007-11-12 13:38:59 · 3 answers · asked by Anonymous in Biology

I'm in the Chicago suburbs. When I was a kid, back in the 70's, it was rare to see a brown ladybug. Now, living in the same area, 35 years later, it seems like it's rare to see a red one.

What happened to all of the red ones? Natural selection? Or, some toxic pollution problem? Do you still have red ladybugs by you? If so, what region of the world do you live in?

2007-11-12 13:38:27 · 48 answers · asked by Maureen 7 in Other - Science

plez help this paper is due and i only have 2 qs left

2007-11-12 13:35:45 · 1 answers · asked by bethany l 1 in Earth Sciences & Geology

What exactly is a maximum bending moment?

Is it the maximum bend a structure (in my case, a sheet pile) can withstand without failure?

Please help! thank you~

2007-11-12 13:34:07 · 2 answers · asked by Anonymous in Engineering