Science & Mathematics - 5 February 2007

Please explain your work. . .

2007-02-05 13:37:49 · 8 answers · asked by mistersponge 2 in Mathematics

I've tried this problem but no success, can someone please explain? Thanks

For a movie scene, an 85.0 kg stunt double falls 12.0 m from a building onto a large inflated landing pad. After touching the landing pad surface, it takes her 0.486 s to come to a stop. What is the magnitude of the average net force on her as the landing pad stops her?

2007-02-05 13:37:21 · 2 answers · asked by oscarv_56 1 in Physics

2007-02-05 13:36:19 · 6 answers · asked by whatsinaname07 1 in Biology

2007-02-05 13:35:03 · 3 answers · asked by whatsinaname07 1 in Biology

2007-02-05 13:35:02 · 3 answers · asked by Anonymous 3 in Biology

What is the mass of 38.2 ml of dry air at STP?

I figure I need to use PV=nRT (solving for n)

[(760)(.0382)] / [(.0821)(273)]
= 1.30 mol (rounded)

but, I don't know where to go from there to finding the mass...

Any help is appreciated!

2007-02-05 13:33:29 · 1 answers · asked by Jess S 1 in Chemistry

I need an inequality, I can find my way after that.

A candidate needs 5000 signatures on a petition before she can run for a township office. Experiece shows that 15% of the signatures on the petitions are not valid. What is the smallest number of signatures the candidate should get to end up with 5000 valid signatures.

2007-02-05 13:33:22 · 6 answers · asked by Anonymous in Mathematics

"What happens to contrast and resolving power when the aperture of the condenser of a compound light microscope is decreased?

2007-02-05 13:33:13 · 1 answers · asked by whatsinaname07 1 in Biology

"In order, list the lenses in the light path between a specimen viewed with the compound light microscope and its image on the retina of the eye."

2007-02-05 13:31:17 · 2 answers · asked by whatsinaname07 1 in Biology

2007-02-05 13:29:34 · 2 answers · asked by Thorny 1 in Astronomy & Space

2007-02-05 13:28:32 · 7 answers · asked by walkin_blues02 2 in Zoology

2007-02-05 13:27:53 · 2 answers · asked by in 30mins 3 in Other - Science

I need to prove that a Quadrilateral with the length of the sides being a,b,c and d, with an area of S, that 4S is less than or egual to (a+b)(c+d), somehow using twice the area of a triangle is absin Theta where theta is the angle between the sides of lengths a,b and sin theta is less than or egual to 1,with equality if theta is a right angle.

2007-02-05 13:27:49 · 3 answers · asked by rolifer@verizon.net 1 in Mathematics

The temperarture is supposed to be 212 F...

2007-02-05 13:27:40 · 1 answers · asked by kiLLah 1 in Chemistry

I am an open-minded Christian who believes God created the heavens and the earth, but I was wondering what theories are out there, being the science geek that I am. :)

2007-02-05 13:27:39 · 8 answers · asked by biblethumpinmaniac 2 in Astronomy & Space

like in regards of air...or on land and space and stuff????

2007-02-05 13:27:26 · 7 answers · asked by rhea777 2 in Astronomy & Space

Large trees? conduction
turbines? convection
windows? convection
white paint? radiation
drapes-convection
tint?-radiation
boxing (house)- radiationC

2007-02-05 13:26:54 · 3 answers · asked by ghettoco 1 in Earth Sciences & Geology

Assume the half-life of the substance is 34 days and the initial amount is 116 grams.

Whats the formula in terms of t? A=?
How long would it talk to decay to 2.3 grams.

Thanks

2007-02-05 13:26:29 · 3 answers · asked by J R 2 in Mathematics

how do u find the amount of force I would need with each turn of the handle and total amount of force for a screw jack or jack screw to raise books at a distance of 20 cm?
pitch=2 cm.
books=10 kg
distance=20 cm.
force=circumference of about 150 cm.

to find input force- 10kg*20 cm./2*3.142*radius (75)
so that with be 200/471= 0.42

to find the total amount would be 471/0.42=1121.43

if i used the same about of books with a pulley system. which of the machines has a greater mechanical advantage?

pulley system would be ?

2007-02-05 13:23:09 · 1 answers · asked by ghettoco 1 in Physics

Suppose that f(x)=ax+b, where a and b are real numbers. Given that f(f(f(x)))=8x+21, what is the value of a+b?

2007-02-05 13:21:56 · 8 answers · asked by Anonymous in Mathematics

do u use prefixes in ionic compounds?
are molecular and covalent compounds the same?
when must parentheses be used in writing formulas?

2007-02-05 13:21:04 · 5 answers · asked by mike 1 in Chemistry

Solve Solve Using Addition Methed
(1) x+13y=14 (2) 2x+2y=19
5x+y=14 2x - 2y=5

(3) a -b=2 (4) 2x - y=8
a +b=2 4x + 3y=36

2007-02-05 13:20:11 · 2 answers · asked by hajileluv69 1 in Mathematics

2007-02-05 13:20:06 · 2 answers · asked by Ali 5 in Geography

Just curious. I live in SW Wisconsin, and it was MINUS 18.9 degrees Farenheit this morning at 6AM.

2007-02-05 13:19:47 · 48 answers · asked by awanderingelf 4 in Weather

I need help with these combined factoring problems:

1. a^3 +16a^2 + 64a

2. w^5 - 10w^4 + 25 w^3

3. 5a^2 + 10ab - 40b^2

4. -3xy^6 + 3xy^2

Thanks for the help!!!

2007-02-05 13:19:44 · 7 answers · asked by Mia16 3 in Mathematics

it is 4 a home work assignment. i need to know about coyotes

2007-02-05 13:17:51 · 3 answers · asked by furisded 3 in Zoology

we were doing a lab today and i got stumped by this:
when you heat a can over a flame for a few seconds and then put it into a tray with water, why does the water get sucked into the can when before, when not heated, it floated??

2007-02-05 13:17:21 · 1 answers · asked by Anonymous in Chemistry

2007-02-05 13:17:00 · 9 answers · asked by MaryBeth 7 in Weather

In the space to the left, write the letter of description in red that best fits each term. You will not need to use all descriptions.


1. nucleus
2. chromosome

3. DNA

4. gene

5. cytoplasm
6. enzyme
7. photosynthesis

8. selectively permeable

A. takes place in the chloroplasts
B. a section of the DNA molecule that codes for a specific enzyme or other protein
C. allows some molecules to pass through but not others
D. the control centre of the cell
E. the molecule that contains the genetic instructions for the cell
F. applies pressure to the cell walls
G. consists of one DNA molecule and a variety of proteins
H. a protein that speeds up a chemical reaction
I. a material in which the nucleus and organelles are suspended

2007-02-05 13:16:51 · 5 answers · asked by ronni_macaroni 1 in Biology

2007-02-05 13:16:43 · 3 answers · asked by Anonymous in Earth Sciences & Geology