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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,684 
force between two charges is it electric force or electromagnetic force?
And force between the atom nucleus and the...

Aug2408 03:00 AM
mite

2 
1,228 
An antenna behaves like an RCL circuit.
The R is the radiation resistance corresponding to energy actually radiate....

Aug2308 06:36 PM
fisico30

2 
3,739 
Hello:
In Classical mechanics, the lagrangian of a system is defined as the kinetic energy minus the...

Aug2308 05:55 PM
Troponin

1 
1,238 
I'm trying to solve the question b) in this linkhttp://i36.tinypic.com/2h3wmtx.jpg
My reasoning is
dK = dm v^2...

Aug2308 10:12 AM
Mårten

1 
1,549 
Hi this is my first post here so I hope it's in the right place!
I am doing a computer course and we are using...

Aug2208 09:58 PM
Andrew46826

0 
1,956 
Dear All,
Please excuse my ignorance of physics. According to some Russian research 1 mW of microwave radiation could...

Aug2208 07:18 PM
mgb_phys

3 
1,552 
Hello, please forgive my ignorance. I need help coming up with a formula I can't seem to find on the internet. ...

Aug2208 02:57 PM
clem

1 
1,283 
Starting with the equation of motion kx = ma , it is said that integrating this with respect to x gives the equation...

Aug2208 11:18 AM
Narcol2000

2 
2,014 
How would I go about calculating the resonant frequency of a tube with a slit cut out from its length. I'm looking for...

Aug2208 11:04 AM
phdpe

0 
1,020 
prove this claim in landau ...
Closed systems have lagrangians which do not contain time explicitly

Aug2208 08:33 AM
pardesi

0 
1,242 
It is a wellknown consequence of classical electromagnetism that any accelerating charged particle must radiate (not...

Aug2108 05:35 AM
Shooting Star

24 
5,383 
Hello,
I want to know how long time a running runner needs to reach a point, when he is initially running in the...

Aug2108 03:03 AM
ManuTOO

0 
1,217 
Hi.
What is a ¨charge¨ ? What does it mean that an electron has a negative charge?
What is modified in particle...

Aug2008 10:56 PM
Defennder

1 
970 
Im trying to calculate energy of the turbines to lift an airplane , by this way, calculating potential energy...

Aug2008 10:49 PM
rcgldr

6 
1,759 
According to Coulomb's law we have that the force between two charged particles could be described by
(1)~~~F = k...

Aug2008 03:59 PM
Mårten

35 
4,376 
So I was doing this one problem in which there is a sphere of radius r and charge density row and there is a spherical...

Aug2008 10:21 AM
atyy

15 
2,573 
Dear Experts,
Are there any effects that could be induced with electrity in a microgravity environment that can...

Aug2008 07:29 AM
Andy Resnick

1 
1,369 
I am doing an experiment on the pendulum, and i wanted to do something on the damping, i understand a little as i have...

Aug2008 06:29 AM
amppatel

3 
2,156 
I have a statics question. In my book under a picture it says.
"To save material the beams used to support the...

Aug2008 02:18 AM
rdbateman

5 
1,660 
Hello, good afternoon.
I would ask you for the help of my work in physics.
As you well understand, I'm not North...

Aug1908 01:21 PM
azimovas

6 
2,711 
hi..i'm an undergraduate student.i'm working on my final year project. i've been looking for the permittivity and...

Aug1908 11:59 AM
antenna

2 
1,249 
Hey all,
Just a bit of background info:
I'm doing an investigation on low temperature plasmas and one of the...

Aug1908 08:40 AM
DaleSpam

1 
2,285 
My boss and i were considering he following problem (see attached image):
2 unequal masses rotate an equal...

Aug1908 08:36 AM
jasc15

3 
5,290 
I have posted this question earlier also. But i am changing my sentences a bit.
This is regarding conservative and...

Aug1808 10:15 AM
i_island0

16 
1,810 
is there another way of considering the specific heat capaciaty of a material (many gas) other than with respect to...

Aug1808 03:56 AM
gemt

4 
1,489 
Suppose an object is suspended above the Earth, then released. It immediately accelerates to 32.2 f/s^2. There should...

Aug1708 06:35 PM
TVP45

55 
8,359 
Hello,
I've come up with a simple, imaginary situation that bugs me. Could someone help resolve my confusion?
...

Aug1708 05:09 PM
DaleSpam

2 
1,290 
** edit: did I forget how to use tex, or is there a system bug? I'll type the formulas normally below the tex
I'm...

Aug1608 04:09 PM
tony873004

2 
1,162 
Hi all,
I'm having some difficulty with electric flux.
Does electric flux stay the same if you double the...

Aug1608 04:07 PM
atyy

6 
2,544 
With all the mechanical forces in statics problems I can assume the sense and I might get a negative answer which...

Aug1608 11:22 AM
merryjman

2 
1,222 
Hi all, new guy here. I am trying to understand the laws that govern a diesel motor. I know it compresses air at about...

Aug1508 10:07 PM
DaleSpam

1 
1,205 
Hi,
I was wondering about the path a charge placed in a solenoid that was flown through by alternating current...

Aug1508 05:10 PM
h0dgey84bc

1 
1,338 
hello
I just can't swallow the idea of mechanical advantage.
* if you have a 10 KG mass , you need , say , 100 N...

Aug1508 04:08 AM
ali171

6 
1,671 
I have a simple lever with two points of equal force, each at a different distance from the fulcrum.

What I...

Aug1408 08:43 PM
russ_watters

25 
3,278 
Looking for some pointers on how to approach this problem:
I'm considering a system like the following  two...

Aug1408 10:08 AM
matematikawan

5 
8,244 
I know a reference frame moving at constant velocity is a inertial reference frame.
Is a reference frame that is...

Aug1308 02:31 PM
DieCommie

3 
1,672 
what would be the speed of a bullet on decline fired from a pistol. firing angel is 45Deg. What would be the speed of...

Aug1308 04:31 AM
tinytim

1 
1,338 
In an electric current there must be forces that push electrons in a general direction (current). My question is, what...

Aug1308 12:09 AM
Phrak

12 
2,596 
Part of my early morning ritual involves making myself a nice cup of coffee.
I pour my aromatic brew into the cup...

Aug1208 06:26 AM
Aquafire

0 
971 
I recently caught a question that I realized was far more difficult than expected. Someone asked how hard they would...

Aug1108 06:37 PM
Topher925

10 
3,238 