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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,943 
Hello all.
I am having a substantially difficult time with what should be, actually, a very simple problem.
I...

Jan1408 02:45 PM
mda

1 
4,546 
Greetings,
I would think this question belongs in a "Electromagnetics" section, if it is not relevant in this...

Jan1408 01:18 PM
Troels

4 
6,205 
Newton's 2^{nd} law states that:
Let us assume that a train of 1000 tonnes is moving with a constant velocity...

Jan1408 08:27 AM
awvvu

2 
11,054 
The Hamiltonian, H=\frac{1}{2}\vec{\varsigma}K\vec{\varsigma} is given.
With K being a 2n \times 2n matrix with...

Jan1408 03:18 AM
jarra

0 
1,527 
Hey guys,
I'm trying to figure out how the pulley system / gearing works on something like this ...

Jan1308 08:37 PM
anchange

1 
3,686 
Could someone PLEASE explain tension to me? Even a link to another site than can explain it would be great. For some...

Jan1308 07:10 PM
Twilit_Truth

4 
2,701 
if ice is heated to say 20C so it melts (done so slowly) is work done during the melting process equal to the latent...

Jan1308 06:15 PM
DaleSpam

22 
3,971 
Hello! I'm doing a research work about projectiles and i thought of crossbow system. I am currently studying using...

Jan1308 03:43 PM
eXniTheR

1 
1,582 
I read that em waves get generated by oscillating and/or accelerating charges. I am confused on how this occurs....

Jan1108 01:41 PM
torquerotates

6 
3,966 
Here's a simple question. Anyone who knows the answer can save me from some effort by telling the answer.
For...

Jan1108 04:23 AM
jostpuur

7 
2,362 
Hello. This is a first post for me.
Do Maxwell's equations alone allow for propagating waves in charge/current...

Jan908 08:43 PM
olgranpappy

10 
2,552 
The textbook I'm using states Kepler's first law in the following form: all planets move in elliptical paths with the...

Jan908 07:13 AM
Shooting Star

3 
2,332 
I realise that there has been a post recently concerning this sort of thing but i think it went a bit off topic for me...

Jan908 06:13 AM
pkleinod

2 
1,918 
Simply, all I want to know is the value of the relative permeability of lead??
Can I assume this value to 1??

Jan908 05:45 AM
shatou

2 
4,093 
I'm completely confused because of a previous post on Newtons second law and magnetism! Can someone help me to find a...

Jan908 02:45 AM
Troels

4 
1,567 
I once read an article that said the average weight of a cloud is equal to eight elephants. I know that they are very...

Jan908 01:03 AM
CaptainQuasar

3 
2,401 
I just read the following from http://www.physicstoday.org/vol57/iss10/p11.html. Could anyone shed some details...

Jan708 10:30 AM
Tanja

7 
2,408 
If I have 2 electrical adapters for a specific device, which has the following information on them:
1...

Jan708 08:40 AM
Shooting Star

6 
2,137 
We have bees flying in a jar, not touching it. Jar is closed and air in it has standard atmospheric pressure. Here is...

Jan608 05:35 PM
russ_watters

43 
24,189 
consider a symmetrical solid body. we say its centre of mass is at its geometric centre. that is, for uniform density...

Jan608 12:29 PM
arildno

1 
12,429 
The General Information about the game:
The law of the Football game says that the ball should be a sphere of leather...

Jan608 11:11 AM
vidhatanand

0 
6,439 
Hi Newbie here so please go easy on me..!
To keep this within my ability to understand can we please live in the...

Jan608 09:45 AM
44HP

6 
1,988 
Hi,
I am having two doubts about the fringing field capacitance.
1) In most of the formulae, the fringing...

Jan608 03:55 AM
Dekar

0 
11,246 
I've unsuccessfully been looking for a decent proof of Chasles' Theorem which states that any rigid body displacement...

Jan508 09:51 PM
EFuzzy

4 
6,676 
Hello
I've been reading optics (both the cartesian and real/virtual sign convention) and I have some queries:
1....

Jan508 03:02 AM
zimrock

14 
3,447 
Can anyone tell me how to i can calculate the amount of load an electromagnet will pull. the electro magnet has 3...

Jan508 12:56 AM
amit_sarda

3 
1,521 
There was an interesting problem that appeared in POPTOR 2005:
A generator consists of a parallelplate capacitor...

Jan308 07:38 PM
Troels

3 
4,031 
I heard that one can solve 2D problem with conformal mapping of complex numbers.
Is it possible to use this method...

Jan308 03:22 PM
marcusl

3 
3,719 
Hi, the physics department at my (undergrad) college is looking around for a good Thermodynamics book for next...

Jan308 01:22 PM
mbrmbrg

1 
3,254 
I've only just completed high school, but I have a decent grasp on basic undergrad maths/physics. After hours and...

Jan308 01:57 AM
Shooting Star

28 
3,205 
Is there any physical law that prohibits the continuous generation of a reactionless torque using a series of...

Jan208 04:33 PM
russ_watters

1 
3,363 
what exactly is the cutoff ratio, in physical terms?

Jan208 03:57 PM
brewnog

2 
3,954 
I searched for this and get conflicting results. I have setup a demonstration that has a erlymeyer flask with a one...

Jan208 01:11 PM
paul k

10 
3,414 
I have a simple question about work. Work is force times distance, in the direction that the force is applied. So...

Dec3107 08:47 PM
Robert100

10 
7,377 
Why is the above notation used instead of Sum_x Exp(b H(x))? Does the "Tr" notation above have anything in common...

Dec3107 04:37 PM
YaroslavVB

12 
3,428 
can anyone proove "kelvin plank" statement of second law of thermodynamics or atleast show that it is always followed...

Dec3107 07:47 AM
sadhu

4 
3,273 
Hi all,
I'm posting here because I see an apparent paradox between what intuition and equations tell me. I'm sure...

Dec3107 02:11 AM
animalcroc

7 
2,538 
Hello, I was recently browsing through on of my physics books, and I came upon the following statement:
"Newton was...

Dec3007 06:19 PM
Integral

2 
1,885 
So.. we've got a 2D crystal, corresponding an infinite square net with +e0 charges in each one (see the atached...

Dec3007 04:40 AM
Istvan

2 
3,255 
why is there a factor of 1/4 in front of the two tensors? Is it formulated that way for convenience?

Dec2907 11:29 PM
Parlyne

1 
3,857 