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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
48,224 
will it be correct if i define head on collision something like this:
When, in a particular reference frame, the...

Sep2208 12:22 AM
i_island0

3 
871 
I'm having a problem with a project I've been kicking around for some time now.
This arose out of a discussion with...

Sep2108 09:32 PM
gettinlate

4 
1,239 
Hello Everyone.
I understand that the taylor series approximate a function locally about a point, within the radius...

Sep2108 04:24 PM
atyy

2 
1,354 
Consider a hot pizza from the oven. Why do you tend to burn your tongue on the cheese, but not the crust?

Sep2108 03:38 PM
marcusl

10 
2,384 
Ok, while rummaging through the internet, trying to find out the magnitude of water's pull on charged objects, I came...

Sep2108 10:17 AM
phox2

2 
1,729 
Hi Guys,
I know that the compressible Euler Equations are:
\partial_t (\rho \mathbf u) + (\mathbf u \cdot...

Sep2108 09:06 AM
dcs23

1 
1,896 
Hello!
I have a couple of questions concerning Lagrangian and Hamiltonian mechanics.
First of all, are...

Sep2108 04:34 AM
Heirot

10 
1,992 
Hi,
I understand the motion of a gyroscope through considerations of torque and angular momentum, I have no issue...

Sep2108 01:49 AM
granpa

3 
1,967 
I'm having trouble understanding fictitious forces, so I looked up the wiki for it...

Sep2108 01:07 AM
putongren

0 
1,570 
Hi all,
I'm a little stumped with how the dielectric increases capacitance. The general solutions all involve using...

Sep2008 06:27 PM
kcodon

4 
21,713 
I know that the force of friction is the (coefficient of friction) x (normal force). My question is, why isn't area...

Sep2008 01:33 PM
chandangang

10 
10,947 
Hello,
I know this has already been asked (unfortunately without answer)... learning once again for an exam...

Sep2008 06:38 AM
flix

9 
6,315 
Currently reading over some lecture notes on Hertzian dipoles and I want to confirm my understanding on why the...

Sep1908 06:43 PM
Antenna Guy

4 
2,915 
Hi everyone! Im a UK grad student working in acoustics. My own background is in EE, so i am largely self taught in...

Sep1908 10:38 AM
stephen_E

5 
1,377 
Hi, all. A friend challenged me to prove that F = grad(U), and now that I did, I'm thinking of submitting it to the...

Sep1908 02:38 AM
atyy

5 
7,215 
Hi All,
I would like to know what is the precise meaning of the internal resistance of a DC source of voltage. ...

Sep1908 01:26 AM
shreason

1 
1,053 
Anyone know where I can find the Symon's Mechanics exercices solved?

Sep1808 11:34 PM
jtbell

2 
7,988 
How would you define headon collision? I am having confusion in definition itself
Among the following, which one...

Sep1808 07:44 PM
i_island0

15 
3,272 
I have an ordinary differential equation of second order. I am looking for the Lagrangian(s) for which this equation...

Sep1808 06:59 PM
atyy

2 
1,630 
I figured with how big the internet is, there would be an entire forum on magnets somewhere out there for me to ask my...

Sep1808 05:58 AM
clem

1 
1,030 
If you go down a mineshaft, gravity reduces because the pull of gravity is due only to matter between r=0 and the...

Sep1708 11:23 PM
olgranpappy

8 
1,348 
Hello!
I'm trying to grasp the "intuitive" meaning of the thermodynamical potetials E,F,H and G, or at least of...

Sep1708 06:29 PM
sisife

5 
1,710 
Hi All,
I am new here and this is not a homework question... I'm turning 40 this year and my retention of physics...

Sep1708 04:13 PM
microguy

2 
1,042 
Hey all,
I trying to get somewhere with the following problem and am not having much luck. Any tips or suggestions...

Sep1708 01:53 PM
Doc Al

1 
1,585 
the fundamental basis of the lagrangian formulation is the fact that the virtual displacement are perpendicular to the...

Sep1708 01:27 PM
Machinus

4 
15,581 
How does a cathode heater work? Can't seem to find a straightforward explanation anywhere.

Sep1708 05:54 AM
ZapperZ

1 
1,406 
Hi,
John Baez has written an interesting article on a subject I was looking for the answer to (...

Sep1708 04:36 AM
atyy

8 
8,909 
Hi guys,
I'm trying to implement the enthalpy equation in C++ converting it from an excel macro I found on this...

Sep1608 11:49 AM
Mike222

1 
1,725 
Hello,
I have to learn about the classic Perturbation Theory.
I'm looking for guides, text books etc about...

Sep1508 12:09 PM
Theherod

2 
1,120 
I know it when I see it but what is the exact definition of a wave? what makes a wave a wave?

Sep1408 09:04 PM
skydancer46

18 
3,268 
I'm just learning about linear momentum in classical mechanics and I have a question about it. I'm not sure I...

Sep1408 12:56 PM
fluidistic

2 
981 
Hello people,
In an AC circuit, how is RMS current and Mean current defined as?
What is the practical meaning of...

Sep1408 03:28 AM
Andrusko

1 
1,344 
Would it be possible for a symmetric axial vector torque to be equivalent to the shear stress of two uniform...

Sep1308 05:07 PM
tinytim

1 
2,511 
Does anyone have the following book:
"Problem Solving in Electromagnetics, Microwave Circuit, and Antenna Design...

Sep1308 02:35 PM
fisico30

0 
1,008 
If two dielectric materials with dielectric constants k1 and k2 and thickness d1 and d2 are within two copper plates,...

Sep1308 12:58 AM
atyy

6 
2,452 
Anyone can tell me why there is a ve for the z= r cot theta for the picture shown below? thanks!
...

Sep1208 11:36 PM
Defennder

1 
3,366 
Wind turbines / hydroelectric turbines  I think the same fundamental Physics applies to my question. The fluid...

Sep1208 06:25 PM
rcgldr

9 
2,863 
hi!
I have a question regarding work done lifting an object vertically upwards, under water.
I am aware that work...

Sep1208 06:02 PM
Andy Resnick

7 
3,495 
I guess this question is very easy, but after it occurred to me, it has been torturing me for quite a while.
I...

Sep1208 11:43 AM
tinytim

6 
1,997 
May I know what does polarization direction for linearly polarized plane waves mean?
In general, does the...

Sep1108 10:33 PM
felicity87

2 
1,975 