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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,708 
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 
3,299 
Consider mass m_{1}and m_{2}with position vector (from an inertial frame) \overrightarrow{x_{1}} and...

Jan1011 05:21 PM
ManishR

4 
632 
We know basic classical mechanics is timereversal invariant while there is a concept of irreversibility in...

Jan1011 11:42 AM
GeorgeRaetz

7 
1,707 
I am refering to the book "Introduction to Electrodynamics" by Griffiths p317, Energy in magnetic field.
\Phi =...

Jan1011 11:15 AM
kloptok

17 
1,850 
Hello!
I want to know something about how is equation for rolling friction derived. Equation is listed below.

Jan1011 08:25 AM
71GA

0 
699 
Hello i tried to calculate Bernulli's equation myself and i get negative pressures on both sides of equation. What am...

Jan1011 04:43 AM
lalbatros

3 
1,200 
If the velocity of a stone is the same in all cases, what determines how high the water splashes when hit by the stone?

Jan911 07:47 PM
Sniperman724

4 
1,483 
(I have myopia.)

Jan911 06:35 PM
Redbelly98

3 
1,060 
Hello there.
I have some difficulty in understanding the condition for a rigid body standing still (or rotating)....

Jan911 05:01 PM
AlephZero

7 
1,654 
Why cant trajectories in phase space intersect?

Jan911 04:19 PM
Rocky Raccoon

1 
2,091 
Does 1 metre cube of air really weigh 1kg?
This is so hard to believe. So heavy?

Jan911 04:15 PM
russ_watters

7 
997 
Hello:
I am a new member in this forum. :smile:
I have question about this equation  in thermodynamics : {...

Jan911 01:33 PM
rock.freak667

1 
568 
Okay, please don't ask me why I would want to do the following; I'll try to explain..
I am writing a program and...

Jan911 09:34 AM
ProtossHeat

2 
631 
http://oi55.tinypic.com/zmr0k.jpg
Questions are located at the bottom of the diagram..

Jan911 08:51 AM
ProtossHeat

0 
1,621 
Hello,
Im looking at how to find out the Amp meters squared of a multi turn solenoid, preferably with an easy to...

Jan911 05:06 AM
mvan4310

0 
1,656 
Hello all! :smile: You know, I thought I knew something about ideal gas mixtures, but now I am not so sure. I am...

Jan811 11:16 PM
Andrew Mason

1 
1,933 
I'm trying to figure out how to determine how long a spring should be to drop a known weight a known length? For...

Jan811 07:56 PM
Redbelly98

1 
2,524 
Hi guys!
I want to ask something about escape velocity.
I know the definition of EV "escape velocity is the...

Jan811 07:50 PM
MRbrs

6 
1,033 
I thought that the idea that the speed of light is a constant in every reference frame came from the MichelsonMorely...

Jan811 02:50 PM
lavinia

4 
640 
I have just read about the principle of Doppler effect.
However there is a point which seemed a bit tricky. ...

Jan811 10:37 AM
Doc Al

5 
771 
This is a question which I have been been tossing around for some time. By looking at gravitationally induced...

Jan811 10:32 AM
hermitme

6 
5,055 
My Physics teacher yesterday said something that gave me pause. He was talking about the necessity of clearly...

Jan811 09:51 AM
MJay82

2 
1,955 
Why are two (angular and linear) magnifications? Aren't they linearry proportional to each other?

Jan811 06:26 AM
kompabt

0 
1,128 
I am a bit confused about the definition of elastic collision.
What i have studied is, elastic collision is one in...

Jan811 05:51 AM
kalesony

19 
6,680 
do you know any text or reference with extensive treatment on electromagnetic field ,potential & electromagnetic...

Jan711 10:14 PM
Born2bwire

3 
600 
How many watts of power would it take to get a a mass of 1kg up to 300m/s? Leaving out friction, drag, etc.. Just how...

Jan711 04:19 PM
kloptok

10 
3,196 
I'm having a difficult time understanding how the coulomb came to be around as a unit of charge. The definition that a...

Jan711 03:30 PM
nasu

1 
1,614 
I apologize if this is in the incorrect category...
Can somebody please explain the Exponential Model associated with...

Jan611 08:03 PM
FantasyQueen

0 
1,737 
This is interesting...
How will the length and the mass of a golf club affect how far the ball will travel? What...

Jan611 07:46 PM
morrobay

4 
1,745 
When certain quantities are measured, the measured values are known only to within limits of the experimental...

Jan611 11:34 AM
balboa

7 
1,227 
For a body to undergo uniform circular motion, a centripetal force which is perpendicular to the velocity at all times...

Jan611 10:41 AM
I_wonder_why

4 
3,956 
Dear all,
For a computer graphics rendering routine, I'm looking for an efficient way of computing the net Fresnel...

Jan611 07:46 AM
Matthias_H

0 
1,214 
For the digital cameras, is the zoomin is equivalent to move forward the camera? My simple camera gives me 5 level...

Jan611 07:46 AM
Andy Resnick

4 
881 
Ok, there's a bit I don't understand in my lecture notes. The maths doesn't seem to quite work out. Any help would be...

Jan611 06:46 AM
yjx

2 
1,305 
In deriving the plane wave solutions of Maxwell's equations in vacuum, one assumes from the very start that the E and...

Jan611 04:09 AM
Born2bwire

22 
5,260 
What I'm asking is this: I'm researching bridge designs for a balsa wood bridge, but I'm wondering why that the...

Jan611 02:59 AM
Studiot

3 
771 
This is my first year teaching High School Physics and I'm finding there are a lot of questions I should have asked 25...

Jan511 08:58 PM
AlephZero

3 
1,637 
If I apply 1 newton to 1 kilogram (at rest) for one second, it will have accelerated to 1 m/s^2 and traveled 0.5...

Jan511 11:45 AM
Doc Al

11 
2,282 
Like if something is going in a circle of radiues R at speed v with angular velocity w, then w=v/R. Where does this...

Jan411 05:46 PM
platonic

6 
2,269 
So suppose we have two dielectrics in contact and we want to know how \mathbf{D} varies across them, then we can use...

Jan411 04:15 PM
Meir Achuz

13 
2,576 