Science & Mathematics - 2 November 2006

I am conducting an investigation in which I am measuring the period of a pendulum. I know that my timing equipment has an accuracy of plus or minus 33 milliseconds. The pendulum's I am testing usually have a period on the order of one or two seconds. How do I figure out how many trials I have to do with each pendulum to get a mean value within x% accuracy?

2006-11-02 19:36:11 · 4 answers · asked by Noachr 2 in Mathematics

could someone go through the steps of writing 3-3i in trig form?

2006-11-02 19:34:06 · 8 answers · asked by fdsfsjk k 3 in Mathematics

2006-11-02 19:32:37 · 6 answers · asked by OU812 5 in Astronomy & Space

CuSO4
KNO2
Mg[OH]2
CH3COONa
Fe[OH]2
Fe[OH]3
Na2SO4
CaSO4
FeSO4
AgNO3
FeSO4
MgCl2
PCl5
HI
KI
NaI
NaF
AlCl3
MgCO3
HCN
KSCN
Fe2O3
KMnO4
KCr2O7
Cr(OH)3
FeS
K2SO4
Li2SO4
LiOH
NiSO4
AgCl
HBr

2006-11-02 19:27:30 · 2 answers · asked by la montée 4 in Chemistry

2006-11-02 19:25:59 · 7 answers · asked by flavorlicious 2 in Earth Sciences & Geology

An airplane flying parallel to the ground undergoes two consecutive displacements. The first is 75km 30° west of north, and the second is 155km 60° east of north. What is the total displacement of the airplane?

2006-11-02 19:25:39 · 4 answers · asked by Some Guy 2 in Physics

a. one
b. two
c. three
d. four
e. answer not given

2006-11-02 19:23:46 · 5 answers · asked by set2k6 1 in Biology

you can take even only left R-modules

2006-11-02 19:22:21 · 3 answers · asked by bhanu 1 in Mathematics

Thanks for your help....tom science 3

2006-11-02 19:22:10 · 3 answers · asked by Thomas M 2 in Earth Sciences & Geology

What is the centre of mass of hollow cone.

2006-11-02 19:18:38 · 6 answers · asked by elvenprince 3 in Physics

if 52 rooms sell at a price of $90
for every $5 increase 4 fewer peop;e buy a room
there is a max of 56 rooms to sell

at what rate should the rooms sell at?
at that price how many rooms will sell?
&
What is thae max revenue?

Thanks Just need to check the answer I got

2006-11-02 19:16:17 · 4 answers · asked by relms2000 1 in Mathematics

anyone familiar with XTT or done XTT assay before? according to product manual, the more viable cells, the more XTT rings it cleaves and more orange formazan accumulate. therefore when the OD is read, absorbance is higher for samples with more live cells, right? absorbance is lower for the wells with more dead cells right? but my result shows the other way round. the more pathogen protein i put in, the higher the absorbance.
I used a medium with phenol red (although not recommended). i suspect my protein change the pH of medium, thus it change colour. but i also have control wells that contain cells, medium and protein (without phenol red), the protein doesn't chnage the colour(pH) of medium. the readings for the wells (no XTT) is consistant.
Is the graph i got correct (absorbance increase when pathogen protein concentration is increased)?

2006-11-02 19:16:13 · 1 answers · asked by snow_cat 1 in Biology

2006-11-02 19:14:47 · 14 answers · asked by Anonymous in Physics

2006-11-02 19:12:10 · 5 answers · asked by Brittany R 1 in Zoology

A. calculate its momentum.
B. Convert the speed of the truck to km/h.
C. A small dogs runs onto the road ahead of the truck. if the driver reacts in 0.75 s, how far does he travel before applying the brakes?
D. Compare this distance if he had been travelling at 60 km/h

2006-11-02 19:10:59 · 2 answers · asked by Bomer 1 in Physics

To Whom it May Concern,
This is basically the area of the Pacific between the mianland U.S. and Hawaii showing the aviation winds aloft at the varying levels from the ocean surface to 40,000 feet if possible.
The aviation Flight Service Station has these charts with the little arrows but from what I understand it is a paid for site. I am looking for a free site. The winds are usually included on these charts. I have already found the NOAA site with the written numbered winds and temps. Thank you out there. Mark.

2006-11-02 19:09:23 · 4 answers · asked by Mark K 1 in Weather

2006-11-02 19:09:10 · 11 answers · asked by Anonymous in Engineering

i saw it in lord of war

2006-11-02 19:05:03 · 3 answers · asked by krishna s 2 in Chemistry

If so , how? (simply!)

2006-11-02 19:03:21 · 15 answers · asked by Anonymous in Chemistry

i need derivation . this question is placed in www.plus2physics.com but i am unable to open this site

2006-11-02 19:03:18 · 2 answers · asked by Anonymous in Physics

I m having a transformer having primary of 230 vac and secondary of 12 vac.
by using secondary as primary and giving 12vac input can I get 230vac at secondary? is it possible?

2006-11-02 18:57:51 · 5 answers · asked by abhay_akulkarni 1 in Engineering

three friend deside to give a one presant to common friends so they had puchase one item by 75 $ by contribution of 25 $ but shopkipper deside to give a discount for 5$ so shop boy gone for to return 5$,in between shop boy had think to take 2 $ from 5$ at last he give only 3$ to that three friends & they had distribute 1$ each
now costing of presant is
3 friend * 24 $ = 72 $
shop boy had taken + 2 $
---------
74 $
but actualy frist they had expence 75 $ - 74 $
so where is 1 $ ? ? ? ? ?????????????

2006-11-02 18:56:35 · 4 answers · asked by ashishv_patel 1 in Mathematics

Well of course they twinkle at night and we see them like every night. First I wanna say what's the difference between a star and a planet? How are stars different than planets? Are stars always bigger than the sun or earth?

2006-11-02 18:55:53 · 7 answers · asked by Anonymous in Astronomy & Space

I know that you measure the strength of a light in candles.

2006-11-02 18:49:23 · 6 answers · asked by Keith the Christian 1 in Physics

2006-11-02 18:47:01 · 4 answers · asked by Dund pund se 2 in Chemistry

these question about the macroeconomics today and the keynesian model.

2006-11-02 18:45:22 · 2 answers · asked by Noor A 1 in Physics

Two 100 watt incandescent light bulbs failed immediately in a three-way light socket. Three- way bulb worked following failures. Failed bulbs made in Mexico by Philips.

2006-11-02 18:45:10 · 5 answers · asked by zig 1 in Physics

2006-11-02 18:41:42 · 5 answers · asked by Anonymous in Engineering

2006-11-02 18:41:36 · 2 answers · asked by Anonymous in Botany

My bf and I were coming home on the porch was this big bug that was at least 2-3 inches long and had a big fat stomach and back side where it was striped the rest was brown i was frightened didnt get a great look any ideas what it was ?

2006-11-02 18:38:47 · 7 answers · asked by Kat 2 in Zoology