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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,885 
Hi all,
I'm working with the heat capacities definition and I have got a confusion. I don't understand why we can...

Jan2812 03:52 PM
dapias09

5 
1,650 
Hello all,
I'm confused with the center of mass concept. Regard the following problem, we have a spring with...

Feb512 12:37 PM
James_Harford

3 
1,184 
Hi,
can anyone help me to understand why the pressure of a ideal solid is zero?. In my class we calculated this in...

Apr1412 03:17 PM
dapias09

0 
736 
Hi all,
Can anyone explain me why the ratio Cp/Cv is infinite for a photon gas?
Thank you in advance.
Diego.

Jun412 12:12 PM
dapias09

0 
1,015 
Hi all,
what do you understand by a hardpoint gas?, I mean in terms of its hamiltonian.
Thanks in advance.

Aug1813 05:10 PM
Jorriss

3 
342 
Hi guys,
I would like to know if the answer given to this thread is correct
...

Sep1513 10:45 AM
dapias09

4 
536 
Hi guys,
I've got a doubt concerning to the minimum mechanical work and the workenergy theorem. Consider the...

Nov2713 03:06 PM
dapias09

2 
642 
Hi guys,
In a scientific paper, I have found the following sentence:
"...given the fact that the system is...

Mar1114 04:48 PM
UltrafastPED

3 
267 
uhm, can somebody help me about this subject? i find it very hard. i'm using foundations of statistical and thermal...

Sep1207 09:59 AM
dareymon

0 
1,497 
Hi . I am making a robot that is supposed to detect a red ball with a camera, and then know where the ball is .
The...

Jul711 06:23 AM
Born2bwire

4 
3,096 
Hi there, does any of you know a place where I can find the derivation of the hydrodynamic equations (navier stokes,...

Jun112 11:38 AM
Andy Resnick

2 
910 
When I was a kid listening to a transistor radio under my pillow late at night I used to wonder whether turning the...

Oct111 06:24 PM
vk6kro

2 
991 
The power generated from the aerogenerator is from the kinetic energy of the wind which pass throught it. So, after...

Aug2904 10:30 AM
Clausius2

20 
4,352 
The situation is there is a ball attached to a string in a car, and the angle that the string makes is measured when...

Nov611 02:15 PM
DarkBlitz

2 
2,053 
Hey,
I came across this question in my text book, and there isnt an answer for it in the back, so I would just like...

Jan1212 12:51 PM
DarkBlitz

4 
1,408 
Hey, I was doing some revison for a test and i came across this question which I cant get my head around
a...

Jan1612 11:18 AM
AlephZero

5 
1,382 
I am having some trouble understanding the concept of electromagnetic waves, I suppose because I expect them to be...

Dec2308 03:38 AM
valleyman

1 
1,248 
I was under the impression that everything was at least slightly, even if imperceptibly, magnetic because all matter...

Jun1110 12:24 AM
netheril96

5 
3,231 
Why do scientists say that certain conditions hold in a vacuum despite the fact that no vacuums exist or are known to...

Jun2311 01:44 PM
I like Serena

4 
1,023 
Hey everyone!
I recently picked up a motorcycle for class/work commutes because walking home at 11pm from the lab...

Apr2709 08:01 AM
Andy Resnick

5 
1,322 
Hello, its my first time in this forum, i've registered because sometimes i have some physics questions during my free...

Aug3111 02:16 PM
DarkFalz

5 
1,936 
Hello,
i have the following questions. Lets assume that i throw a ball with mass 1kg and velocity 10 m/s at a wall...

Mar212 09:39 PM
apb000

2 
736 
Hello, first of all, I must say that I am quite knowledge lacking in the thermodynamics topic, I am just seeking some...

Dec613 01:03 AM
Simon Bridge

17 
1,022 
For several years i have thought about air (fluid) resistance without getting deeper into the formulas that model its...

Jan814 05:14 PM
A.T.

1 
481 
I am in a disagreement with someone on another forum.
There is wheel with a freewheeling hub constrained to roll...

Jun1510 08:33 PM
K^2

15 
3,029 
Hi!
I'm reading this paper on fluid dynamics:
http://jcp.aip.org/resource/1/jcpsa6/v50/i11/p4831_s1
Its equation...

Aug2012 02:07 PM
DarkLindt

1 
418 
I'm writing up a prac that involved LCR circuits.
One part of the prac involved measuring the phase difference...

Sep1110 11:57 AM
Bob S

1 
1,605 
Hamilton's principle is described as
\deltaI=\delta\intL dt = 0
so as the action is stationary.
This...

Feb212 08:00 PM
Darkmisc

2 
1,902 
How did Hamilton work out that action is the stationary quantity for a mechanical system?
I've seen proofs that...

Feb412 04:03 AM
ardie

1 
1,119 
i know triple point is the temp. that water's(here use water as example)
solid、liquid、gas state can be existent .
...

Feb2410 10:46 AM
Gokul43201

2 
861 
Is there any way possible a magnetic field can cancel out an electric field?
Thanks !

May1711 01:30 PM
berkeman

6 
3,739 
is there a way to keep inertia in circular motin?

Oct904 02:44 AM
spacetime

5 
4,323 
Something strange showed up while I was thinking about the following problem: I'd like to prove, by the only mean of...

Jun1309 08:55 AM
Mapes

3 
857 
Hello everyone, I am trying to understand COMSOL 3.5 and I am interested in Photonic crystal fibres and tapered...

Jan1510 01:34 PM
multiphysics

3 
4,218 
Hello,
In this problem: http://www.physics.harvard.edu/academics/undergrad/probweek/prob1.pdf
Two balls are...

Feb1509 04:03 PM
darkSun

2 
1,369 
Let's say we have an electric field,
(ax, 0, 0). (a is a constant)
The divergence of the field is a, so the...

Jul1309 03:22 PM
clem

4 
5,917 
Hello, I have a question about a spinning symmetric top:
When the equations of motion are solved, they are solved...

Aug2710 12:30 AM
darkSun

8 
2,200 
i understand what a sine wave is, as well as the hertz. but im curious as to why all energy travels in a wave and not...

Dec2609 09:35 AM
dE_logics

4 
5,507 
This is the material i read from textbook, and it doesnt make any sense to me!! can somebody plz help me out if they...

Sep2507 06:37 PM
TVP45

4 
4,131 
This is one of the Maxwell's Equations that I cant understand:
\oint E.dl = \int dB/dt .dS
From what I...

Oct407 09:57 AM
vanesch

4 
2,321 