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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
45,931 
So a cube submerged in water will experience pressure on all six sides, and the pressure on the bottom will be greater...

Jul714 06:51 AM
DaleSpam

8 
630 
i was told that progressive waves has no nodes, why is it so? can anyone here explain please?

Jul714 04:30 AM
Simon Bridge

1 
223 
If I hold the top end of a straw filled with water, the water stays in the straw which is due to the atmospheric...

Jul714 12:56 AM
Simon Bridge

3 
337 
Hi guys. I hope this isn't a bad place to post my question, which is:
I'm reading some lecture notes on Lagrangian...

Jul614 10:38 PM
Travis091

4 
382 
So the formula is F=Gm1m2/r^2. Could you substitute one of the mass values for an energy value since gravity attracts...

Jul614 09:32 PM
MrR

6 
375 
Hey guys, I don't know if here is the right section for this question but anyway. So I was looking for the proof or...

Jul614 08:54 PM
UltrafastPED

1 
406 
I am facing difficulty in understanding a key point . Hence I am putting it here instead of Introductory Physics...

Jul614 12:32 PM
Delta²

11 
1,179 
Hey 
I am a bike mechanic with a large interrest in physics. I know that a larger disc brake rotor provides a...

Jul514 12:16 PM
90245

20 
24,030 
Suppose I have such an equation:
A= f(B)
so A is a function of B.
Can I really use the fact that a variation of A...

Jul414 11:08 PM
Matterwave

4 
478 
Hello, I am working on non linear fluid dynamics with my professor. We are trying to model multiphase flows of...

Jul414 08:44 PM
Simon Bridge

1 
428 
I am currently reading "Quantum Physics of Atoms, Molecules, Solids, Nuclei, and Particles" by Robert Eisberg and...

Jul414 06:12 PM
hideelo

4 
624 
How does a moving point charge affect another point charge moving at the same velocity and separated by some distance...

Jul414 03:15 PM
DaleSpam

12 
1,131 
I have two questions that I think are analogous (tell me if they are not).
1. If I have a spring scale and apply 50...

Jul414 01:07 PM
Doc Al

2 
407 
Please watch this video (link: http://www.youtube.com/watch?v=JNA3RryOC8) for reference.
As you can see, the...

Jul314 10:45 PM
Simon Bridge

5 
613 
I've heard that a changing electric field creates a magnetic field and a changing magnetic field creates an electric...

Jul314 08:32 PM
Wittyname6

15 
953 
Dear,
I studied 4f system and I've got a question.
As far as I know, 4f system is optical filtering system (attached...

Jul314 01:18 PM
UltrafastPED

1 
589 
This is one very basic question. But I just need to confirm if I understood it right.
Suppose a particle moves...

Jul314 12:40 PM
Adjoint

2 
612 
sound created by blowing accross the top of the bottle produces sound due to standing waves created on air inside the...

Jul314 03:03 AM
A.T.

5 
755 
when you slide your thinger around the rim of glass it produces resonance
the matter which vibrates is a glass,...

Jul214 03:59 PM
olivermsun

6 
852 
Hello,
I was thinking about how would capillary action change in a tube (classic example) and in a tube fitted...

Jul214 02:03 PM
Alfred1

2 
746 
I got this Lagrangian on the exam and it just seems weird to me:
L = \frac{m}{2}(ẋ²+ẏ²) – eBẋy
What I mean by...

Jul114 02:51 PM
dauto

10 
1,025 
To what I know, surface tension is a force that appear at the interface between 2 bulk phases, and is parallel to that...

Jul114 10:24 AM
quangtu123

2 
643 
Hi to all.
I'm looking for ways heat could be converted directly to electrical energy. I figured out some machinery...

Jul114 06:43 AM
UltrafastPED

2 
764 
I understand that in a two body problem under central force, corresponding to a potential V(r)(assume one body is...

Jul114 05:53 AM
Philip Wood

3 
724 
I'm working on the electromagnetic stressenergy tensor and I've found this in a book by LandauLifshitz:
...

Jul114 01:50 AM
TSC

14 
856 
Can light travels without electromagnetic field ?
Thanks

Jun3014 12:20 PM
Quarlep

7 
1,217 
Hi! everyone...
I'm a building a standing frame for disabled children, the structure in elemental form is shown in...

Jun3014 08:11 AM
Harsh188

2 
755 
I notice on this page at Rice University that regarding Newton's 3rd law it says that...
Surely this is a...

Jun3014 04:49 AM
A.T.

1 
567 
Hi
Let a classical particle with unit mass subjected to a radial potential V and moving in a plane.
The...

Jun3014 04:24 AM
vanhees71

3 
598 
I really want to know if there is a difference between the force from the first impact of water and the force from...

Jun2914 08:44 PM
TumblingDice

10 
1,237 
I am looking for an equation that correlates material failure and collision speed;
so that I can better understand...

Jun2914 07:34 PM
caz

2 
615 
I have problem undestanding newton's III law. When i press the wall the wall react with the same force on me but as I...

Jun2914 04:43 PM
ultrauser

42 
3,072 
Hi  I am currently working on a paper verifying some thermal hydraulic code against experimental test data for...

Jun2914 03:59 PM
Q_Goest

2 
638 
I am working through Leonard Susskinds 'the theoretical minimum' and one of the exercises is to show that...

Jun2914 03:36 PM
WannabeNewton

1 
593 
If the speed of light is changing, does this mean that the permattivity and/or permeability are dynamically changing...

Jun2914 09:38 AM
athosanian

6 
1,174 
Take a closed system of particles. Each has it's own mass, but that's really about it for the sakes of this argument....

Jun2714 05:51 PM
Jano L.

6 
653 
Hey everyone,
A meager pea brain (me) is in need of some help from you fine physics gentlemen.
This is a concept...

Jun2714 03:24 PM
Volkr16

3 
522 
As it's stated in Newton's law of gravitation, every object with mass attracts all other object with a force which...

Jun2714 02:57 PM
Matterwave

12 
1,056 
One page 5 in Landau & Lifshitz Fluid Mechanics (2nd edition), the authors pose the following problem:
The...

Jun2714 10:57 AM
mSSM

6 
632 
Recently on an aquarium related forum, I called out someone for making what I considered to be an outlandish claim and...

Jun2714 09:19 AM
Overflowing

17 
2,529 