Science & Mathematics - 19 November 2007

A vertical spring with k = 480 N/m is standing on the ground. You are holding a 5.1 kg block just above the spring, not quite touching it.

(a) How far does the spring compress if you let go of the block suddenly?

(b) How far does the spring compress if you slowly lower the block to the point where you can remove your hand without disturbing it?

(c) Why do your answer differ?

2007-11-19 17:38:18 · 2 answers · asked by Anonymous in Physics

2007-11-19 17:37:44 · 2 answers · asked by Anonymous in Mathematics

2007-11-19 17:37:30 · 6 answers · asked by Frank Le 1 in Chemistry

2007-11-19 17:36:47 · 4 answers · asked by naenae 1 in Earth Sciences & Geology

I need to make 100 mL of Mg( NO3)2 and I need to know how much magnesium I need.

I have HNO3 which is 16 M (molarity). I need to know how much Magnesium I need to dissolve in the nitric acid (HNO3) to make 100 mL of Mg(NO3)2, which should have a molarity of .1 M.

1) I wrote out the balanced equation

Mg+ 2HNO3= H2 + Mg( No3)2

2) I calculated the amount of moles of Mg(No3)2

.100 L *.1 M= .01 mol Mg( No3)2

since M1V1=M2V2, there are also .01 mol of HNO3

3) .01 mol HNO3* 1mol Mg/2Mol HNO3*24.31g/1 mol=

.122 grams Mg

ok so my answers is .122 grams. other people though got .24 grams! am i right? or maybe to write out the balanced net ionic equation? i dont know

2007-11-19 17:34:33 · 4 answers · asked by Anonymous in Chemistry

A car dealer is preparing to sell 100 cars on an auction day. He sets the price for a SUV for $1250 and a Matrix for $850, how many cars of each type should the dealer stock in order to get the greatest profit at the end of the day?

2007-11-19 17:30:40 · 3 answers · asked by Anonymous in Mathematics

I asked a question on here a few days ago about a dream I had. One answerer told me about an eerily similar dream she had about a "purification"

Im wondering who believes there is a chance we are in the middle of a "purification".... or some kind of "ethnic cleansing"... our gov't in th US is giving vaccines that cause illnesses & break our bodies down. Our gov't is not supporting natural births, and leaving women no option but to put their children on formula milks (no natural immunitites from breastmilk, also food in cans is incredibly vulnerable to contamination). We are using "anti" bacterial products on everything and there is an increasing number of resistant bacteria, diseases, fungus, virus, plants, etc. The meat/dairy/egg industry is filling animals full of hormone/anti biotics and those travel to the consumer. The military is under scrutiny for vaccine deaths/reactions...

Why are people so hesitant to believe something is going on here?? What could be going on?

2007-11-19 17:25:47 · 7 answers · asked by Anonymous in Paranormal Phenomena

Suppose the total cost (in dollars) of manufacturing x units of a certain commodity is
C(x)=3x^2+16x+300
At what level of production is the average cost per unit the smallest. ___________________.
At what level of production is the average cost per unit equal to the marginal cost. ________________

2007-11-19 17:22:16 · 3 answers · asked by Ksyha 1 in Mathematics

2007-11-19 17:17:10 · 1 answers · asked by Anonymous in Mathematics

2007-11-19 17:13:59 · 4 answers · asked by casey s 1 in Botany

Using a highly sensitive parabolic sound collector, Tom records the frequency of a tuning fork as it drops into the Grand Canyon. He drops the vibrating tuning fork from rest at t=0. He records a frequency of 1653.0 Hz at t=4.870 s. What is the natural frequency of the tuning fork? Use Vsound=343.0 m/s.

anyone have any equations that relate these values?
thank you

2007-11-19 17:11:36 · 1 answers · asked by Zmik 3 in Physics

home". What purpose does it serve? I hear but don't listen to criping except to get a take on where the "mind set" is functioning/ (get me on that grammar. I confess, not so good.) Sinking in the problem seems, well, redundent. I am not a Rocket Scientist. I hold no Akolades in Any Area. I am not called upon for my opinion or "take".

I am questioning our motives. I am questioning things that simply don't make sense. We can accept complience and apathy forever. The forever part will be short lived but it will be what we allowed, (accepted). My question? Does anyone have the goal of fixing "real problems"? Acceptance and Apathy are Kicking Our Butts. Everyone knows it but noone stands up, votes or questions any of it. Why? That is my question. Why? I have my answer already. Please do not respond with antagonist, mean-spirited remarks. None needed. I want Answers or Solutions. I want "Helpers". Thanks.

God's Speed and Grace,
Nancy
nme1022@yahoo.com

2007-11-19 17:08:00 · 6 answers · asked by Nancy E 2 in Other - Science

I heard that following the rythm of "The Bee Gees song " Staying Alive " gives the right amount of rythm for CPR

2007-11-19 17:07:12 · 4 answers · asked by yeah 2 in Medicine

For ex, would this be absolutely convergent or divergent
inf
E (-1)^(n-1) ((5n^2+2) / (4n))
n=1

2007-11-19 17:03:35 · 2 answers · asked by swt16 1 in Mathematics

if there r two different gases in the same container with the same # of moles, do they have the same pressure?

like, H2 and O2 have the same # of moles. do they have the same pressure when they'r in the same container?

2007-11-19 17:00:39 · 3 answers · asked by Ganbatteru 3 in Chemistry

Find the dimensions of a rectangle whose perimeter is 46 cm and whose area is 120 cm square.

2007-11-19 16:55:40 · 10 answers · asked by Cesar F 1 in Mathematics

2007-11-19 16:50:52 · 10 answers · asked by Jose T 1 in Geography

Hi i need help with these simple algebra questions , these are the only ones i am stuck on. It is for Algebra II. We are currently on the topic of simplifying radical expressions.


1. sqrt(40 a^3 b^4)

2. 2 * sqrt (24m^4n^5)^ (1/3)
( which reads as 2 multipled by the third root of 24m^4n^5)

3. sqrt( (1/32)w^6 z^7) ^ (1/5)
( which reads as the fifth root of 1/32 w^6z^7

2007-11-19 16:50:12 · 2 answers · asked by ique4life 1 in Mathematics

Is the statement, "In most biology expieriments, the relationship between independent and dependent variable can best be described as cause and effect," True or False?Why

2007-11-19 16:49:30 · 1 answers · asked by Tony 1 in Biology

2007-11-19 16:46:54 · 4 answers · asked by Goodfriend 1 in Other - Science

...Please

2007-11-19 16:45:58 · 5 answers · asked by Duchess 2 in Mathematics

2007-11-19 16:44:48 · 3 answers · asked by Deepa 2 in Physics

find the area under the standerd normal curve between z=0.53 and z=1.24

2007-11-19 16:43:09 · 4 answers · asked by jim k 1 in Mathematics

2007-11-19 16:40:12 · 5 answers · asked by surreal_j04 1 in Biology

What do you think of the testimonials given by people who had NDEs and all the interesting research based on it?

2007-11-19 16:40:03 · 13 answers · asked by mitchchan 5 in Paranormal Phenomena

at 345 volts dc, how much current can a standard size paper clip have running through it?

2007-11-19 16:37:46 · 3 answers · asked by Alex 3 in Engineering

I'm talking power wise

2007-11-19 16:37:31 · 3 answers · asked by Anonymous in Biology

2007-11-19 16:35:28 · 2 answers · asked by I want my two dollars? 3 in Physics

2007-11-19 16:34:52 · 5 answers · asked by **Smalls** 1 in Biology

2007-11-19 16:34:46 · 5 answers · asked by Anonymous in Astronomy & Space