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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,810 
is it, cause velocity isn't.

Jan1511 04:12 PM
Mueiz

60 
9,353 
Hi there,
Is hydrogen gas transparent to most radiation or is there a wavelength that interacts with hydrogen?
...

Jan1511 03:35 PM
mathman

3 
964 
A point charge accelerating through space generates an electric field and radiates energy. But how is this influenced...

Jan1511 03:00 PM
haas101

2 
1,716 
I’ve seen this problem phrased several ways and posted several times – a couple of times by me. But I have not seen an...

Jan1511 02:57 PM
RonL

38 
3,704 
Hi,
I write here for the first time and i hope so far i am doing everything properly :rolleyes:
I am writing about...

Jan1511 02:26 PM
Kiquin

2 
3,715 
Ok first let me say compared to most of you I'm an Idiot... lol...
I understand the basic laws of physics and drag...

Jan1511 01:35 PM
RickinMD

4 
874 
So I'm really interested in the field of wave optics, and luckily for my undergraduate program, we get to do a...

Jan1511 09:02 AM
Andy Resnick

6 
1,018 
I know from the movie that paper burns at fahrenheit 451. I guess this refers to the activation energy paper and...

Jan1511 03:07 AM
Borek

3 
1,349 
Hi,
Im trying to understand the relationship between heat released in an energetically favourable chemical reaction...

Jan1411 06:17 PM
Studiot

1 
1,268 
Effect of a volume increase at constant temperature: A constant temperature means that the average kinetic energy of...

Jan1411 02:14 PM
NobodySpecial

3 
914 
Hello there!
I have a situation as follows:
http://img821.imageshack.us/img821/4026/kuglananagibu.gif
I have...

Jan1411 01:53 PM
pinsky

7 
1,756 
Hello all,
I'd like to calculate the inductance of a straight current carrying wire per unit length of wire.
The...

Jan1411 03:59 AM
Phrak

10 
4,546 
as you all know the equation for centripetal force is (m((2 pie r)/t)^2)/r). ok so imagine this. a weight attached to...

Jan1311 09:07 PM
K^2

5 
1,306 
One form of the third law of thermodynamics states that ; in absolute zero temperature,entropy is absolute that means...

Jan1311 06:33 PM
DaleSpam

6 
1,042 
I need the general expression for the lagrangian density of a linear elastic solid. I haven't been able to find this...

Jan1311 05:42 PM
jambaugh

1 
1,111 
Ok, I still don't understand heat. As I see it, heat is the measure of how fast atoms are moving. And energy is also...

Jan1311 02:31 PM
HallsofIvy

6 
1,034 
i have 2 questions regarding magnetic field...
1)if 2 identical charges move parallel to each other(along y axis)...

Jan1311 09:57 AM
kloptok

2 
776 
I have this problem.
Imagine, in 3D space, a rocket that has to go to a certain point in the minimum possible time,...

Jan1311 09:40 AM
pgimeno

8 
1,428 
Lets say we have an infinite current carrying wire and it is wrapped with a dielectric materiel.
Lets say the...

Jan1311 07:30 AM
cragar

4 
1,686 
Hi all,
I'm trying to find which magnetic materials can operate without too much losses at about 2.45 GHz and have...

Jan1311 06:22 AM
D4V1D3

0 
1,253 
What is the reason that there are 4 different thermodynamical potential?
How can I know, which of them should I use?

Jan1311 05:02 AM
pabloenigma

13 
2,012 
Hi
I'm trying to get a better understanding of dispersion in light. Specifically, the relationship between...

Jan1211 07:47 PM
Beermonster

9 
2,671 
Hi All,
I’m new here so please forgive me if this isn’t the right section to post in.
This is a bit of an epic...

Jan1211 06:58 PM
jack action

1 
1,228 
I'm still having trouble with this:
Generically, work = m * d^2 / t ^2 (mass, displacement, time)
If to a 1kg...

Jan1211 06:34 PM
cepheid

6 
1,661 
Basic premise: a pure tone sine wave can be modeled with a pendulum and the rate of amplitude decay can be manipulated...

Jan1211 06:02 PM
dulrich

1 
2,629 
Hello there!
Could someone please help me with setting the starting equations for coupled oscillators. I'm having...

Jan1211 02:13 PM
neelakash

8 
1,508 
Hello
How would you calculate the total force (due to air pressure) on the top face of a prism, which is partially...

Jan1211 11:58 AM
MrMatt2532

1 
2,302 
Hello everyone.
I have a problem...I'm calculating natural frequency of a standing cylinder.
In order to do that,...

Jan1211 07:26 AM
mahavidyas

1 
1,882 
how to obtain the scattering extinction coefficent of a spherical particles illuminated by a bessel beam? thaks!

Jan1211 04:46 AM
soberprogress

0 
1,230 
I'm wondering about entropy, free energy and disorder. I see entropy defined along the lines of "the amount of energy...

Jan1111 08:53 PM
Mapes

9 
1,665 
On the picture below you see the motionless black sphere and the green rod rotating around it. At the Position A the...

Jan1111 03:54 PM
gneill

25 
3,818 
Hello, i don`t understand why it is said that the heat involved in a chemical reaction at constant pressure is the...

Jan1111 01:50 PM
zalook

0 
883 
I want to verify my understanding about skin effect and plane wave of conductor wire.
...

Jan1111 01:48 PM
yungman

6 
1,864 
why the coefficient of friction of screw jack of two pulley is negative in lowering state?

Jan1111 11:56 AM
Andrew Mason

1 
1,650 
Imagine an object is resting upon the floor. The object is pushing the floor with a force mg, which is vertically...

Jan1111 11:11 AM
D H

22 
2,810 
Anyone know of any good papers, research i can view on magnetism, also any equations for working out the force of one...

Jan1111 07:33 AM
Vanadium 50

2 
694 
For plane wave travel in +ve z direction in a charge free medium, the wave equation is:
\frac{\partial^2...

Jan1111 04:04 AM
Delta²

3 
1,727 
 We know that for closed systems, energy transfer between the system and the environment can be in the form of heat...

Jan1011 11:43 PM
AirForceOne

3 
1,933 
Hi all,
I recently read an article on economist about Maxwell's Demon. It is mentioned that someone disproved...

Jan1011 08:50 PM
K^2

21 
3,312 
Consider mass m_{1}and m_{2}with position vector (from an inertial frame) \overrightarrow{x_{1}} and...

Jan1011 05:21 PM
ManishR

4 
633 