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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,884 
Hi, i would like to calculate a field after passing through a lens using fresnel integrals.

Sep508 04:48 AM
mdegama

0 
1,366 
what will happen if light passes through changing magnetic field?

Sep508 12:20 AM
atyy

13 
2,369 
My electrodynamics lecturer was talking about how potentials are arbitrary and that's why we have different gauges....

Sep408 02:02 PM
granpa

2 
1,399 
Imagine a hollow sphere made of perfect material.
Its walls are perfectly resistant to any thermal and mechanical...

Sep408 10:09 AM
zoki85

7 
1,279 
Hi,
A simple question:
Is the electric field of a point charge infinite at the charge itself?
Coulomb's Law...

Sep308 06:25 PM
Apteronotus

5 
1,176 
Hi,
I am aware that the effects of a dielectric sphere in a uniform electric field have been done in many...

Sep308 12:36 PM
clem

1 
3,816 
Well i do understand about the 8 fundamental dimensions in physics, but i cannot understand what makes only the...

Sep308 09:52 AM
Count Iblis

5 
1,827 
Hai!!
Can anybody answer to me why the horizontal component of a projectile motion has no net force?Why is it move...

Sep308 08:12 AM
Redbelly98

2 
7,589 
Show that: \left(\frac{\partial z}{\partial y}\right)_{u} = \left(\frac{\partial z}{\partial x}\right)_{y} \left
...

Sep308 06:42 AM
Mapes

3 
4,222 
Hi, just out of curiosity...
Ampere's Law describes that an electric current produces a magnetic field. When...

Sep308 01:39 AM
atyy

42 
6,431 
Four interesting questions:
1: Is there a maximum range of a given electromagnetic field?
2: Is there a maximum...

Sep208 06:40 PM
Constructe

5 
1,130 
Can a wind propelled ice boat have a speed higher than the speed of the wind it is propelled by??
The answer, as i...

Sep208 05:56 PM
rcgldr

3 
1,749 
The other day, my professor mentioned projectiles have a force on them due to their spin. The example he gave is how a...

Sep208 12:53 PM
pimpalicous

4 
3,910 
I wonder if anyone has ever heard this terminology. What is the meaning of a 3vector?

Sep208 12:42 PM
Varnick

6 
5,366 
hello everbody...i got two question about kinetic friction force...
tat is
1. is kinetic friction force of an...

Sep208 12:07 PM
rcgldr

2 
4,143 
My friend and I wondered this in junior high school: since a record (as in the kind played on a record player) or an...

Sep208 07:01 AM
cabraham

13 
7,465 
Hi everyone,
The subject of this topic is what I am looking for. For example if the concentration of a monovalent...

Sep108 08:04 PM
DaleSpam

14 
4,781 
Problem 1.8 from a Goldstein's mechanics text, is (verbatim since it's hard to describe otherwise) :
"A system is...

Sep108 01:03 PM
Peeter

2 
1,964 
What is the reasoning behind defining the helmholtz free energy as F = kT ln Z?
I always wanted to know why it was...

Sep108 12:55 PM
Count Iblis

4 
2,910 
hi there i am studying lagrange and hamiltonian mechanics.
i came about this question from a previous test session...

Sep108 12:51 PM
Count Iblis

5 
1,932 
If one has a diatomic molecule with energy levels
\epsilon_l = \frac{h^2 l(l+1)}{2I}
l = 0,1,2,3,4,5...
...

Sep108 12:42 PM
Count Iblis

1 
1,273 
please explain to me this phenomena (Details in the picture attached)
 after answering my 2 questions , I would...

Sep108 07:30 AM
Doc Al

1 
913 
I have a question about the 3D stress distribution. I need to know the shear stress components on a arbitrary plane in...

Sep108 05:23 AM
litters95

8 
12,152 
Hi
can i say that 100 lines in the same direction represents a higher degree of order then
10 lines in the same...

Aug3108 03:17 PM
Doc Al

5 
8,206 
With:
wavelength = 4 meters
frequency = 30 cycles/sec
period, T, = .033 sec/cycle
wave propagation velocity =...

Aug3008 10:41 PM
morrobay

2 
1,606 
If waves collapse upon detection, how is it that the Friis transmission equation yields accurate results?
Regards,...

Aug3008 04:04 PM
Antenna Guy

5 
1,915 
Hello everyone. Take an object in you hands. Throw it in the air. While launching it, your hands will push on the...

Aug3008 02:03 PM
fisico30

11 
4,478 
I'm searching for an example of how to find out generator function for a canonical transformation, when new canonical...

Aug3008 01:19 PM
RicoB

2 
4,250 
I was wondering about this and can't seem to think of a way this could be done so I have to ask. Is it possible to...

Aug3008 10:57 AM
Defennder

18 
4,592 
My physics book shows the direction of static friction to be opposite to an applied force that is parallel to the...

Aug3008 09:41 AM
i_island0

14 
2,361 
My situation is this. I have 6,560 ft (4 lb) of polyurethanenylon coated #27 gauge round wire wound in a coil with an...

Aug2908 09:10 PM
Redbelly98

1 
11,413 
Given the mean energy of a system in a heat bath is
\bar{E} =  \frac{\partial ln(Z)}{\partial \beta}
Where...

Aug2908 07:08 AM
Narcol2000

2 
1,596 
I know that when a Longitudinal (Sound) Wave spreads in water the displacement
of the water particles is parallel to...

Aug2808 04:58 PM
Carter2x

2 
1,608 
According to Bernouilli's law there is a direct relation between pressure drop and fluid's velocity at the throat....

Aug2808 11:13 AM
FredGarvin

3 
1,152 
I'm trying to track down the rationale for removing the cross product of velocity and magnetic field intensity from...

Aug2808 10:13 AM
Defennder

4 
1,356 
Hi, we are doing an experiment and encountered the following problem
We have two cylindrical tubes connected...

Aug2808 08:22 AM
Andy Resnick

3 
1,762 
In many problems , to change the length of the air column we use water but I dont understand why waves dont pass into...

Aug2808 06:02 AM
Yoni

4 
1,158 
Can anyone validate that phase always decreases in the direction of propagation of wave?
Also if i have a sonometre...

Aug2708 09:49 PM
atavistic

3 
945 
Basic electrostatics (as I've seen it presented) usually starts off with an implicit \mathbf{F} = q q_2...

Aug2708 07:31 AM
PhilDSP

28 
7,125 
How can I prove that newtonian potential of nbody problem is homogeneous function of order 1?
Please help!
...

Aug2708 04:56 AM
AmateurNS

0 
1,399 