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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
48,204 
I just read this, from a site dedicated to popularizing science:
" ...think of air as being like water. If you...

Sep1413 10:19 AM
boneh3ad

5 
1,124 
I was looking at a site which described the classic demonstration to illustrate how water pressure increases with...

Sep1413 09:27 AM
voko

3 
515 
Torque, in particular, is always a concept that has confused me.
Can the rules related to torque be derived or are...

Sep1313 10:15 PM
BrainSalad

16 
1,597 
Can an electromagnetic wave be deflected by electric or magnetic field.

Sep1313 04:06 PM
berkeman

4 
389 
My mechanics prof today said when setting GMm/r2 = ma, the canceling of the small m is actually a bit nuanced because...

Sep1313 12:59 PM
mfb

2 
503 
hi,
I'm having trouble understanding what the difference is between the B and H fields. What my understanding is, if...

Sep1313 11:21 AM
rebel rider

107 
33,965 
Howdy everyone, I'm sorry if this is in the wrong forum, but since I believe it is mostly a thermodynamics problem I...

Sep1313 08:52 AM
Scratchy

6 
702 
In my lab I have a TEM00 laser, so there is no electric or magnetic field in the direction of propagation (call it z...

Sep1313 07:43 AM
Claude Bile

4 
536 
Why do we use phasor representation in physics..For example,why we need maxwells equation in phasor form as well??

Sep1313 07:38 AM
Claude Bile

5 
670 
Hi all, as a physics student, I seldom use Fourier transform but from my understanding, given a periodic function you...

Sep1313 07:35 AM
Claude Bile

12 
808 
Hello everyone, My Name is Dwayne McIntosh.
I am not that good at Physics or Mathematics however i do have a...

Sep1313 12:09 AM
quawa99

2 
545 
A glass bulb contains air at room temperature and at a pressure of 1 atmosphere. It is
placed in a chamber ﬁlled with...

Sep1213 09:59 PM
Andrew Mason

1 
730 
Hello everyone,
I've run across an interesting Newtonian physics problem that I'd like some input on. The problem...

Sep1213 06:53 PM
Doc Al

1 
611 
Hello,
I don't know if this is the right place to ask this, but here it is:
Does the brake pad/rotor temp effect...

Sep1213 06:20 PM
CWatters

8 
567 
Hi,
In the case of dielectric in electric field E0, we have E1 = E0 outside crystal and E2 = E0  P inside, so that...

Sep1213 04:00 PM
Anthus

0 
371 
Hello,
I'm trying to imagine how Coulomb would've measured the force between electrically charged objects, but...

Sep1213 11:23 AM
Nugatory

1 
499 
Hello!
Promising that I will not make other new questions in the next days :smile:, I have a doubt about the meaning...

Sep1213 08:47 AM
EmilyRuck

9 
1,584 
Im given this question by my Physics teacher while disscusing thermodynamics. How to Prove that Tv^gama1 = Constant ?...

Sep1213 08:20 AM
dauto

1 
596 
Hi, i would like to know, why the motorized control valve have to fixed at chilled water return pipe but not in...

Sep1213 04:07 AM
cktan22

0 
370 
Hi All,
Thanks again to all the great mentors and contributors to this forum.
I wanted to ask a question about...

Sep1213 03:56 AM
UltrafastPED

2 
449 
How would I go about calculating the pressure of supercritical water at an arbitrary temperature in a closed container?

Sep1113 08:43 PM
Chestermiller

2 
555 
Hello all,
So the total internal energy of a gas as far as I've been told is 3/2(NKT) but it can also be written as...

Sep1113 08:38 PM
Chestermiller

2 
564 
I have a question for which I am intensely confused.
Lets say a car was pushing a big truck from behind. And the...

Sep1113 06:22 PM
DaleSpam

14 
1,110 
I am consistently getting this wrong. To me, in the picture below, it would make sense that the structure would be...

Sep1113 05:07 PM
sherrellbc

2 
599 
In Landau Volume 2 (page 71) an expression for determining the entire electromagnetic Lagrangian is given. What would...

Sep1113 05:03 PM
bolbteppa

4 
530 
So lets say a gas is doing some work against a piston and decreasing its internal energy. Does the gas also do work...

Sep1113 12:02 PM
dauto

2 
422 
How do I calculate the surface temperature of a shipping container's roof over 24 hours? All weather and sun...

Sep1113 07:41 AM
woody726

3 
619 
I was reading the derivation on Wikipedia:
http://en.wikipedia.org/wiki/Group_velocity#Derivation
Why is the...

Sep1113 05:01 AM
chingel

2 
588 
Does anyone have an intuitive explanation for why torque depends on the perpendicular distance from the axis of...

Sep1113 02:53 AM
A.T.

2 
705 
I have a mass (m) at the end of a rigid link of length r, pivoted at the red circle (below).
m is acted on by a...

Sep1013 11:41 AM
DrBwts

3 
494 
The centripetal acceleration of a circle is: a_c = \frac{v^2}{r} * u_n. The acceleration of an ellipse is different. ...

Sep1013 05:03 AM
D H

14 
1,614 
Hi !
I've been thinking this problem a whole and I could not find an answer. I want to solve the following problem:...

Sep913 11:14 PM
ebrattr

0 
489 
So I am probably understanding something wrong but would gauss's law \frac{Qinside}{\epsilon0} for a sphere...

Sep913 07:15 PM
Jolb

1 
655 
Without air resistance, bodies travel in a parabola.
What is the curve that is travelled when air resistance is...

Sep913 05:33 PM
arildno

11 
837 
What is the electric field due to a current carrying wire? In a Griffiths EM problem, he treats the E field outside a...

Sep913 02:54 PM
mikeph

5 
942 
The book that I use (Concepts in Thermal Physics by S. and K. Blundell) states the second law in two ways. The way...

Sep913 10:20 AM
ASmc2

4 
806 
Where can I find a proof for the Ampere Circuital law? Wherever I look, I just find a proof for an infinitely long...

Sep913 08:33 AM
vanhees71

11 
1,558 
Hi,
I am trying to gain a better understanding of the classical model of electrodynamics, so what I mean by this...

Sep913 04:29 AM
voko

1 
516 
Hi,
I've been toying with a thought experiment, and I was wondering if it had any basis in reality. Is it possible...

Sep813 08:51 PM
ajdecker1022

8 
597 
Please help me, what are micro and macrostates, what are accessible states?

Sep813 08:49 PM
DennisN

1 
807 