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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,911 
Hello, is it possible to figure out how much force in newtons is created when a compressed gas expands?

Dec2607 03:55 PM
russ_watters

6 
7,087 
we know that during inelastic collision momentum remain conserved but kinetic energy of system does not
some part of ...

Dec2607 03:19 PM
Shooting Star

12 
2,425 
do gravitational field lines always need to be straight, cant they be just curves
if yes then please tell an...

Dec2607 12:56 PM
sadhu

2 
1,637 
What does the term "Action" means in physics?

Dec2607 12:04 PM
belliott4488

9 
2,007 
how does a transformer work?

Dec2607 01:00 AM
rbj

5 
3,946 
Does anyone know of an experiment that shows that the electrostatic and/or magnetostatic forces have a finite speed,...

Dec2607 12:46 AM
rbj

2 
1,789 
When they say K=1/2mv^2 does K mean the change of kinetic energy? because Wtotal= the change of kinetic energy...

Dec2507 10:59 PM
sadhu

2 
1,770 
hello all, i've been researching a bit of info on lens optics (image propagation mostly), but have only found...

Dec2507 08:27 PM
infamous_Q

0 
2,007 
Hi all,
I was giving a class on dilatation and I have proposed to the students a problem where two pieces of wire...

Dec2507 06:16 PM
DaTario

30 
3,511 

is it true that when the net force...

Dec2507 01:54 PM
Shooting Star

2 
1,836 
I want to find a solid argument why entropy always increases and even more important why it is
S=\sum_i p_i \ln p_i...

Dec2507 08:09 AM
Gerenuk

0 
1,797 
The Ampere's Law is \nabla \times B = \mu J and Gauss's Law is \nabla \cdot E = \frac{1}{\epsilon} \rho
Since J...

Dec2407 06:17 PM
G01

5 
2,224 
Hi! I am new user to this forums and on the start I have one question:
"If I increase the speed of the electrons,...

Dec2407 08:16 AM
Physicsissuef

2 
2,602 
Hello experts,
I hope you can help me with the following problem.
There is one huge pipe (diameter about 3 meters)....

Dec2307 04:30 PM
LURCH

7 
1,237 
Hi all,
I'm a bit confused about ferromagnetism (and I've come to realize that I'm not the only one)! I'm currently...

Dec2207 08:51 PM
marcusl

1 
2,590 
I am trying to figure out a problem. When hydrogen and nitrogen are mixed, the entropy of the gas tends to mix them...

Dec2107 09:43 AM
lilrex

7 
1,382 
if there is a decrease in pressure at constant temperature will there be an increase in entropy?

Dec2007 04:31 PM
Andrew Mason

7 
5,713 
Hi there.
I'm having a problem explaining the physical meaning of the symbols in the equation for an underdamped...

Dec1907 10:06 PM
Cyrus

4 
1,712 
Hey Guys,
I know that this has been posted before, but mine is slightly different.
Our instructor only provides:...

Dec1907 08:16 PM
pervect

6 
13,170 
Can entropy change be zero for a closed system in an irreversible process? If yes under what conditions? Thanks!

Dec1907 12:02 PM
Shooting Star

2 
8,907 
Why do all rays coming from far off distance from a source(may be planar)... converging at a point need to travel the...

Dec1807 12:56 AM
pardesi

4 
1,059 
I am reading Introduction to Mechanics by Kleppner and Kolenkow. I am now reading the articles dealing with...

Dec1707 11:27 AM
arildno

5 
2,835 
Please see this link first: http://en.wikipedia.org/wiki/Precession#Classical_.28Newtonian.29
How do they get to...

Dec1607 06:27 PM
JolleJ

10 
4,276 
having problems trying to understand and derive the equation for intensity in the doubleslit interference pattern. ...

Dec1607 05:28 AM
St_LightStorm

42 
4,455 
My teacher asked us too prove that Hamiltons principle proves that newtons equations of motion hold for N particles....

Dec1607 12:00 AM
frenchyc

4 
2,012 
Voltage = Current * Resistance
Power = Current^2 * Resistance
Magnetic field magnitude of a solenoid = magnetic...

Dec1507 06:39 PM
DaleSpam

5 
3,065 
I conjecture that only spherical symmetric mass distribution can produce radial gravitational force field (according...

Dec1507 04:22 PM
mma

11 
3,131 
Bulb with volume of 5 liters is filled with nitrogen n = 3 molls. The bulb is set in space, the bulb cracks and the...

Dec1507 12:10 PM
Privalov

25 
2,073 
In the chapter on radiation (Chapter 11), Griffiths notes that an electric monopole does not radiate, but also that a...

Dec1507 06:14 AM
Shooting Star

1 
1,159 
Hi all,
If we take the integral of tau (the resultant torque) times the angular displacement theta, with respect to...

Dec1407 09:17 PM
Shooting Star

18 
2,534 
Let's say we have a sphere, radius R, which has a uniform volume charge density. Then we wrap it around with a...

Dec1407 03:28 PM
mda

2 
1,420 
Is it possible that the the small vibrational energies that make up "heat", are caused by the pull of electrons...

Dec1407 02:57 PM
Ben Niehoff

8 
1,127 
We have a springmass system which oscillates in one dimension on a frictionless horizontal surface. We act an...

Dec1407 09:40 AM
olga11

6 
5,594 
Hi all,
I would like to know in which circunstances the third law applies just in the weak form.
Thank you
...

Dec1307 11:09 PM
Shooting Star

6 
1,396 
I have been trying to find the explaination why the wavelength of a wave is the limit of the resolution of an image...

Dec1307 05:42 PM
Claude Bile

1 
10,215 
Light in a vacuum has momentum \hbar k but when the light enters a dielectric medium, fx. glass, the momentum of the...

Dec1307 02:32 PM
clem

2 
2,261 
Hello,
Is it always true that (EB) = 0 ?
If the answer is "no". In which cases is it true ?
Thank you !

Dec1307 01:10 PM
DaTario

1 
997 
As I understand it, conductors interact with EM waves (light) in such a way that
prevents transmission through the...

Dec1307 09:24 AM
silverrose

8 
2,663 
I went for a run and measured time and distance. I wanted to estimate how many calories I used.
Suppose a ran a...

Dec1307 07:17 AM
Shooting Star

1 
2,532 
i found this in a text book.
at a high altitude the temperature of the atmosphere is 500 degrees centigrade. yet an...

Dec1207 06:56 PM
russ_watters

4 
2,280 