Science & Mathematics - 14 October 2007

how would i balance this:
HNO3 + SO2 + H2O --> H2SO4 + NO

please include your steps (algebriacally) to help me understand it a bit more

thanks in advance

2007-10-14 02:08:35 · 5 answers · asked by Jenny K 1 in Chemistry

I'm taking AS physics, and this was on a GCSE recap test, and was the only one I got wrong, so it's been annoying me.

A mass of 5 kg is raised 20m into the air, and this takes 4s. What was the power used?

I have 2 different equations for power -

Power = mass/velocity

and

Power = work done/time

I used the first one, worked out the velocity as 5ms-1, and got the power as 1 watt. But this was wrong. Since I have used the second one and got 125 watts (im not sure if this is right), and I really dont think it is relevant, but in the previous question I found that the potential energy of the mass from 20m in the air is 1000J.

Can someone please go through this step by step, and explain where Im going wrong with having two different power equations. Thankyou.

2007-10-14 02:07:30 · 3 answers · asked by honourableone 3 in Physics

Why are the amplitudes of intensity of the pattern generated by single slit diffraction different (gradually decrease as you go away from the center) and yet with double-slit diffraction the intensity of maxima are constant regardless of distance from the center?

2007-10-14 02:05:36 · 1 answers · asked by thatnaweedguy 1 in Physics

when ammonium thiocyanate & barium hydroxide are mixed what substances can you detect from the smell?& what is the balanced equation?(NH4+ & SCN-)please help

2007-10-14 01:43:02 · 1 answers · asked by ping 1 in Chemistry

a resource centre has 4 copies of a particular film for rental over 1 week perod the demand by borrowers per week is a poisson distribution with mean 3
A) find the expected number of copies that will be rented out in a week

2007-10-14 01:39:17 · 2 answers · asked by ice i 1 in Mathematics

what is the blanced equation of copper sulfate(solution) + steel wool?please help

2007-10-14 01:38:56 · 1 answers · asked by ping 1 in Chemistry

2007-10-14 01:37:06 · 2 answers · asked by shivington 2 in Biology

2007-10-14 01:36:24 · 10 answers · asked by Anonymous in Mathematics

2007-10-14 01:33:04 · 7 answers · asked by Emma S 1 in Mathematics

2007-10-14 01:29:38 · 12 answers · asked by Mavis 4 in Zoology

2007-10-14 01:27:22 · 9 answers · asked by aldrin p 1 in Astronomy & Space

Please HELP!

2007-10-14 01:24:09 · 10 answers · asked by snickernikki727 1 in Mathematics

2007-10-14 01:20:57 · 2 answers · asked by Anonymous in Physics

2007-10-14 01:19:07 · 3 answers · asked by Ashlie P 1 in Earth Sciences & Geology

I was thinking, sure there's been freak incidents of freefall being survived here and there, but has there ever been a device or stunt where a human has been allowed to fall at full speed and strike the ground, AND survive with little to no damage afterward? I am thinking as an example the Pathfinder landing where it bounced for miles, and also the egg drop contests held in every high school. Weight and volume not a problem, only speed as it cannot be slowed down like a parachute or retro rockets. Has there ever been or can there ever be a device, like a hollow geodesic sphere or balloon, that can cushion a human going 200 miles an hour?

2007-10-14 01:18:52 · 1 answers · asked by Jacob L 1 in Physics

2007-10-14 01:15:23 · 8 answers · asked by singh n 1 in Earth Sciences & Geology

we know that......when light ray refracts wavelength changes.....we also know that colour is related with wavelength.......so when a red light ray refracts does it change into another coloured ray?????

2007-10-14 01:11:53 · 6 answers · asked by Anonymous in Physics

The collision between a hammer and a nail can be considered to be approximately elastic. Estimate the kinetic energy acquired by a 15 g nail when it is struck by a 550 g hammer moving with an initial speed of 3.5 m/s.

This is a practice problem from my physics book. So I didn't copy the question incorrectly. It indeed says elastic...

2007-10-14 01:10:56 · 3 answers · asked by Anonymous in Physics

related to surfactant..in monolayer studies..
pls help..

2007-10-14 01:00:03 · 2 answers · asked by summeR 2 in Chemistry

Matrices-calc project please please help?
any form of help is appreciated!
note: i dont know how to make matrices on computer so each of these is a 2 by 2 matrix...just in one set of brackets. numbers before comma are top row, after comma are bottom row

1. Consider matrix M= [2 0 , 0 2] calculate M^n for n= 2, 3, 4, 5, 10, 20, 50. Describe in workds any pattern observed. use pattern to find general expression for matrix M^n in terms of n

2. Consider matrices P=[3 1, 1 3] and S= [4 2, 2 4]
P^2=[3 1, 1 3]^2 =[10 6, 6 10] = 2[5 3, 3 5] ; S^2= same type of thing as P
Calculate P^n and S^n for other values of n and describe any observed patterns

3. Consider [k+1 k-1, k-1 k+1]
steps 1 and 2 contain examples of these matrices for k=1, 2, and 3. consider other values of k and describe any patterns you observe. generalize these results in terms of k and n

4. use technology to investigate what happens when further values of k & n. state scope of limitations of k and n

2007-10-14 00:59:11 · 6 answers · asked by suryakant p 1 in Mathematics

Hi There, Can anyone solve this problem? you can also email me your answers. qaviliom@yahoo.com
Any comments is extremely appreciated.
Regards,
Qaviliom.


Why for m greater than 7 we have:

2^m=< LCM(1,2,3,4,...,m)=< e^m

2007-10-14 00:51:01 · 4 answers · asked by Curious 1 in Mathematics

Does it have something to do with the earth's magnetic field?

2007-10-14 00:44:03 · 7 answers · asked by kai_raitei007 3 in Astronomy & Space

This is with respect to the previous question by me - " prove that there is no positive integer between 0 and 1"

I couldn't find a reply button in the post I made to reply to the posts. Can someone first tell me how to reply to posts in one's own thread?

Secondly, I got this theorem and proof from the book on "Number Therory" by Thomas Koshy..

I have posted the proof as it is in the book. I have no intention to establish the proof. I just thought the author's proof is flawed. If that was not the case I was wrong. Just wanted to confirm that.

Thanks to all of you for your answers :)

2007-10-14 00:43:12 · 2 answers · asked by scw_0611 1 in Mathematics

At which growth stage do you think cyanogenesis would be most appropiate as a defence mechanism in plants

2007-10-14 00:29:11 · 3 answers · asked by Anonymous in Biology

2007-10-14 00:26:42 · 3 answers · asked by Anonymous in Zoology

2007-10-14 00:22:38 · 4 answers · asked by Anonymous in Astronomy & Space

Find the polynomial functionof lowest degree with integral coefficients which has the following zeros.


2, 3+- sqrt of 2

2 + 3to the sqrt of 3
thanks

2007-10-14 00:20:13 · 1 answers · asked by xah8 1 in Mathematics

2007-10-14 00:19:55 · 4 answers · asked by andy 1 in Botany

2007-10-14 00:12:39 · 23 answers · asked by Anonymous in Other - Science

The sum of two numbers is 50. The sum of ¼ of the first number and 2/3 of the other is 25. What are the numbers?

2007-10-14 00:11:04 · 6 answers · asked by isay cute:) 1 in Mathematics