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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,837 
This confusion is about the following problem:
Suppose the entire region below the plane z=0 is filled with uniform...

May1814 09:59 AM
Meir Achuz

5 
302 
Hi, please could someone explain why the magnetic field is stronger at the poles of a magnet. I know that the field...

May1714 08:50 PM
enorbet

3 
346 
http://www.ilrn.com/ilrn/books/spcp07h/Fig_20_14a.jpg
I understand how motional EMF is produced, the magnetic force...

May1714 01:07 PM
BruceW

11 
383 
Hi I'm confused after reading the definitions of physical Quantity and physical property:
Definition from...

May1714 11:00 AM
dauto

3 
414 
Hi, I've read that the speed of em waves in the vacuum is the electric field component frac the magnetic field...

May1714 10:25 AM
mfb

1 
222 
Hello all,
I would like to know a method to trap light. That is, it should be pretty simple and nonelectric. It...

May1714 02:15 AM
albertrichardf

12 
333 
I am trying to make a very strong magnet that will only last for a short pulse, just a fraction of a second, with a...

May1614 10:50 PM
Pharrahnox

2 
237 
When a body is held or rests in equilibrium in contact with a surface (e.g. a slope, the edge of a block etc.) how do...

May1614 05:14 PM
jbriggs444

7 
266 
I am trying to find an equation that tells the strength of a magnetic field a given distance away from the source. It...

May1614 03:04 PM
mfb

22 
22,376 
Hey guys, umm i'm just gonna get straight to the point, why is the notation of dy/dx for example is being abused so...

May1614 10:22 AM
D H

22 
553 
Hi All,
I am thinking about building a simple electrical generator, and I am trying to make sure I clearly...

May1614 05:30 AM
Pharrahnox

7 
519 
When water is vigorously shaken the kinetic energy and, hence, the motion of the molecules increase. Which particular...

May1614 03:05 AM
Simon Bridge

1 
231 
To prepare for a future physics course, I googled Newton’s Laws and then found about the Work Energy Theorem. I can...

May1514 07:30 PM
russ_watters

56 
1,205 
Hello everyone,
I was wondering, is there any way of calculating the time it takes for two objects in thermal...

May1514 07:10 PM
Chestermiller

1 
248 
Hey guys, I've been wracking my brain for a while, and thus I have landed here yet again.
My problem is the...

May1514 12:11 PM
crador

3 
403 
If I have a grounded conducting material, then I know that $\phi=0$ inside this material, no matter what the electric...

May1514 05:42 AM
Simon Bridge

3 
216 
I had a bottle half full of ice and filled it with water and placed it in my fridge. I noticed that the ice was taking...

May1514 04:18 AM
DrClaude

1 
253 
In the semiclassical treatment of the ideal gas, we write the partition function for the system as $$Z =...

May1514 01:38 AM
WannabeNewton

1 
270 
I'm working on research into the feasibility of separating out the infrared rays above 1200 nm in sunlight for solar...

May1414 10:10 PM
SIM77

6 
230 
A new variational principle is presented in this paper: http://arxiv.org/ftp/arxiv/papers/1112/1112.2286.pdf
When...

May1414 02:47 PM
rrhd

1 
203 
To every scalar field s(x,y) there corresponds a 'constant' vector field x = A s(x,y) and y = B s(x,y), where A,B are...

May1414 01:16 PM
UltrafastPED

6 
216 
First, I'm a second year high school physics student so my thinking may be halfbaked. I was wondering what motion a...

May1414 12:24 PM
Agrasin

2 
226 
In a beam of unpolarised light, there are thousands of light waves of all polarisations. At a given point along the...

May1414 11:00 AM
maline

6 
408 
Hello Everybody,
Span efficiency factor appears in the liftingline theory of Prandtl describing Lift and vortex...

May1414 04:07 AM
A.T.

22 
2,087 
I have a question that has puzzled me during the last couple of days. Suppose that there is a system (e.g. a small box...

May1414 01:16 AM
Jano L.

14 
565 
Suppose we have a collection of conductors for which the voltage is specified on some conductors and the surface...

May1314 03:01 PM
komdu

2 
192 
Hey,
It's a simple question (hope so). How do you know (analitically) wether angular momentum is conserved based...

May1314 01:49 PM
stevendaryl

12 
531 
I am trying to calculate the maximum current drawn from a capacitor that is connected to a resistor of a very low...

May1314 02:37 AM
Pharrahnox

4 
270 
Hi,
In EM theory to derive the 'wave equation for electric field in a conducting medium' we make ρfree to be zero,...

May1114 02:55 PM
Shan K

18 
474 
Hi everyone,
I have recently been trying to make a nanoemulsion of an aqueous solution by means of Electrospray....

May1114 02:14 PM
Taylor

4 
235 
Afternoon all,
I am interested to hear any and all suggestions as to how one would go about modelling the rise in...

May1114 02:09 PM
Chestermiller

4 
281 
In griffith's intro to electrodynamics (4rth edition), ch. 3, pg. 121.
here is the second uniqueness thrm for the...

May1114 12:20 PM
WannabeNewton

3 
353 
Hi
1) I am reading Pippard's Classical Thermodynamics and was confused by one of his examples in the attachment.
...

May1114 09:51 AM
rkmurtyp

68 
2,708 
Has anyone ever "fired" an electron down the center of an evacuated tube (horizontally) to see if the electron follows...

May1114 09:20 AM
Vanadium 50

5 
398 
For any ensemble
##dw=f(p,q,t)\frac{dp dq}{h^{3N}N!}##
I do not understand this definition. ##f## is probability...

May1114 03:22 AM
LagrangeEuler

0 
226 
Hello,
It is said that any process accompanied by dissipating effects is an irreversible process.For...

May1114 01:57 AM
rkmurtyp

34 
1,275 
Good afternoon,
I am making way through this paper and I am having trouble "seeing" how the linear velocity AE is...

May1014 11:41 PM
HomogenousCow

7 
347 
Hello, I am having one question about whether we can realize we are moving in a system, or we think that everything...

May1014 05:10 PM
Matterwave

1 
256 
Hello, I am interested in knowing what happens ta wire trough which current is flowing, when an external magnetic,...

May1014 12:35 PM
UltrafastPED

5 
250 
here are the two equations i'm dealing with:
Eq. 1: $$W=\frac{1}{2}\sum_{i=1}^n q_{i}V(r_{i})$$
Eq. 2:...

May1014 02:00 AM
Jano L.

7 
342 