Science & Mathematics - 13 November 2007

A physics professor is pushed up a ramp inclined upward at an angle theta above the horizontal as he sits in his desk chair that slides on frictionless rollers. The combined mass of the professor and chair is m. He is pushed a distance x along the incline by a group of students who together exert a constant horizontal force of F. The professor's speed at the bottom of the ramp is v.

Use the work-energy theorem to find his speed at the top of the ramp.

I know W=K2-K1 and K=.5mv'2 but i dont understand

would it be K= .5mv'2 sin(theta)

I also know F=-kx but how would i equate that for this problem/

please help!

2007-11-13 19:04:51 · 2 answers · asked by Anonymous in Physics

Limit as x-->infinity of sqrt(2x^2+1)/3x-5
This is an example in my book and they've divided numerator and denominator by x and then it became Limit as x-->infinity of sqrt(2+1/x^2)/3-5/x

I don't understand why the numerator is sqrt(2+1/x^2). Please explain. That's all I need to know. Thanks.

2007-11-13 19:00:59 · 2 answers · asked by Anonymous in Mathematics

2007-11-13 19:00:36 · 1 answers · asked by Christian 1 in Chemistry

2007-11-13 18:59:56 · 2 answers · asked by Anonymous in Physics

you believe them, but if there is a "wet paint" sign somewhere, you have to touch it to make sure?

2007-11-13 18:59:38 · 9 answers · asked by Anonymous in Astronomy & Space

2007-11-13 18:53:07 · 2 answers · asked by angelonavaro 1 in Zoology

[2 years ago I was staying in Gulf Breeze, Florida.]

"One night I had a dream, which during it felt entirely real. I saw a creature, greenish/blue with large brown/black eyes that showed me "the universe" and all these civilizations and wars, and different types of "beings". This creature did not speak to me verbally, rather I heard in my mind what I can only say would be the creatures' "thoughts beaming towards me".

Towards the end of the dream it was as if I was being "led home" and showed up until the present day, moving-video-multimedia style history lesson."

[upon awakening i immediately recalled the dream as best i could in writing, as above stated. i don't know if this would be considered a "UFO SIGHTING" or "just a dream"? But I am looking for answers: what is your interpretation of this? should I contact anyone about this, to share this experience, or is it best left "a dream of no significance"? thanks for your sincere answers.]

2007-11-13 18:51:15 · 8 answers · asked by Anonymous in Paranormal Phenomena

system but in the rest of the area kitchen there is no sprinkler system , only a hose reel do i have according to NFPA to add sprinkler system in this kitchen , is there any refrence.

2007-11-13 18:50:14 · 3 answers · asked by gamal 2 in Engineering

that collapse upon impact. What is the advantage of this new design?

2007-11-13 18:50:09 · 8 answers · asked by Hu-Li X 1 in Physics

[2 years ago I was staying in Gulf Breeze, Florida.]

"One night I had a dream, which during it felt entirely real. I saw a creature, greenish/blue with large brown/black eyes that showed me "the universe" and all these civilizations and wars, and different types of "beings". This creature did not speak to me verbally, rather I heard in my mind what I can only say would be the creatures' "thoughts beaming towards me".

Towards the end of the dream it was as if I was being "led home" and showed up until the present day, moving-video-multimedia style history lesson."

[upon awakening i immediately recalled the dream as best i could in writing, as above stated. i don't know if this would be considered a "UFO SIGHTING" or "just a dream"? But I am looking for answers: what is your interpretation of this? should I contact anyone about this, to share this experience, or is it best left "a dream of no significance"? thanks for your sincere answers.]

2007-11-13 18:49:28 · 3 answers · asked by Anonymous in Astronomy & Space

2007-11-13 18:47:38 · 13 answers · asked by Hu-Li X 1 in Physics

2007-11-13 18:46:22 · 4 answers · asked by Brian L 3 in Medicine

If V1....Vn are n linearly independent vectors in R^n, and if C1...Cn are non -zero scalars, prove that the n vectors C1V1....CnVn are linearly independent.

2007-11-13 18:43:21 · 2 answers · asked by X Efficient 1 in Mathematics

Are they supporting it in any way? Financially, morally, etc. ? And do they know of the terrible concequences of the shark-fin industry, not only due to the pain the poor marine animals have to suffer, but also on the wider ecological scale?

2007-11-13 18:40:24 · 2 answers · asked by Warrior 1 in Zoology

Is the wavelength or velocity changed?

I think the frequency will change but I don't think the wavelength or velocity will.

2007-11-13 18:37:56 · 1 answers · asked by JQ 9 2 in Physics

2007-11-13 18:37:56 · 7 answers · asked by Anonymous in Zoology

have any of you experienced a paranormal event? I'm specifically interested in appliances and electronic devices that you believe have been influenced by a ghost or other paranormal factor.

2007-11-13 18:33:23 · 12 answers · asked by Richayyyyyy 2 in Paranormal Phenomena

2007-11-13 18:29:18 · 8 answers · asked by navycs2003 1 in Astronomy & Space

I cannot see by any means how this limit is true. How can it not be infinity??

2007-11-13 18:28:21 · 4 answers · asked by Theava 2 in Mathematics

ok, yesterday i bought a black dress
i got home with my 3 yr old son and put the bag on my blue modula lounge and i took out the bread and poly filler from the same bag.
i knew the dress was in the bag so i did my painting and chores.
later that night i wanted to try it on
and i cannot find it.
i have checked the whole house and wheelie bins outside
i have checked absolutely everything and all im doing now is repeating what i have already checked and its driving me up the wall.
black baby doll size 10 dress from target.
give me an inkling idea plzzz

2007-11-13 18:22:49 · 11 answers · asked by dot 4 in Parapsychology

1.Project topics should be related to renewable energy.
2.Preferable if related to biomethanation, pyrolysis, cogeneration..

2007-11-13 18:15:21 · 2 answers · asked by Ramyaa l 1 in Engineering

Given sequence 〈a_n 〉 n=1 to ∞ defined recursively by a_1=√6,a_(n+1)= √(6+a_n )
Prove that sequence is positive and increasing

Also determine whether sequence is bounded above if so exhibit upper bound if not show that n > 0

Based on conclusion you made above answer whether it converges or diverges

Compute lim as n approaches infinity a_n

Report It

2007-11-13 18:07:36 · 1 answers · asked by Anonymous in Mathematics

Describe the microstructure of a piece of steel after rolling in one direction to achieve a 20% reduction by cold working.

2007-11-13 18:04:24 · 1 answers · asked by claudia 1 in Engineering

I cant figure out why this limit is true:
lim x-> infinity (2x^6+5x^4+7x) / (7x^6-3x^5-4x^3+10x) = 2/7

Why? Is L'Hopitals rule somehow involved?

2007-11-13 18:00:05 · 2 answers · asked by Theava 2 in Mathematics

2007-11-13 17:45:30 · 1 answers · asked by triples3989 1 in Mathematics

2007-11-13 17:41:56 · 2 answers · asked by NarAv 1 in Botany

How do I find the degree of these polynomials?

4x^2 + 12xyz

And

3x^4y^2 - 5x^2y + 3

2007-11-13 17:40:24 · 1 answers · asked by Carissa 1 in Mathematics

my friend apparently overdosed on pandole and only threw up and she had about 5

2007-11-13 17:30:54 · 5 answers · asked by musicpurpledogs 1 in Medicine

2007-11-13 17:30:05 · 15 answers · asked by Joseph P 1 in Mathematics

help solving this equation

2z^2 + 2iz -1 =0

2007-11-13 17:22:19 · 3 answers · asked by Anonymous in Mathematics