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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,701 
As a way to express the complex poynting is F = P + j2ω(Wm − We), whats the magnitude and the phase of it based on the...

Oct2912 08:27 PM
xnoiz

0 
405 
NVM, Wrong section.

Oct2912 11:49 AM
Torald

0 
445 
Please see the attached photo.
I am not sure how to proceed. I do not know Mi or M2, nor do I have enough...

Oct2912 09:09 AM
emKhairol

3 
1,094 
I love physics, but I find that I am ignorant about some of the more basic concepts, so forgive me if this question...

Oct2912 08:53 AM
jtbell

4 
922 
Hello,
I am having difficulty understanding the paragraph in my textbook explaining why no other engine can be more...

Oct2912 08:36 AM
jtbell

2 
907 
hi .. ...
i am entering a sumobot competition..weight limitation 1kg..dimensions 150mm*150mm...what is more important...

Oct2912 04:00 AM
rcgldr

4 
588 
Not sure if I am doing this correct and do not have answer available...
A heat pump takes on 30,000BTU/hr of heat and...

Oct2812 11:41 PM
Andrew Mason

1 
799 
I having a bit of trouble understanding Joos's treatment of virtual displacements. I am referring to pages 114 and...

Oct2812 05:01 PM
Hetware

4 
594 
Alright so I have a question on the work done with constant acceleration up a hill. I was working an example problem...

Oct2812 04:16 PM
Physics_5

2 
760 
Here's the textbook way of calculating the work done by an ideal gas in an isothermal case.
PV=nRT
P.dV=(nRT/V).dV...

Oct2812 12:03 PM
metalrose

3 
1,067 
So, I know that it has been sort of asked in other forms before, but they mostly deal with human beings and so I've...

Oct2812 11:38 AM
wagonseast

10 
1,457 
I am confused why the heat capacity at constant pressure can be different from the heat capacity at constant volume.
...

Oct2812 11:28 AM
Woopydalan

2 
847 
Hi,
It seems that there is no much examples of this particular case.
OK, we all know how to write the general...

Oct2812 11:06 AM
phys_student1

2 
1,062 
If we consider the kinetic energy of say a car like Nissan Leaf moving at its top speed we have :
K.E. = 0.5 x M x...

Oct2812 10:45 AM
Jay_

13 
1,741 
Hello
Please, if you UNDERSTAND WHAT IS MOMENTUM, tell me.
I want to know, why do I need momentum, why was this...

Oct2812 09:11 AM
MaisaraWD

5 
624 
I understand that if two points are inside a conductor they're at the same potential. I also understand that if two...

Oct2812 08:16 AM
andrien

2 
471 
When we consider a magnet, usually we perceive the field lines to come out of the north pole. But since the poles of a...

Oct2712 06:39 PM
Lasand

4 
889 
A little while ago I asked: why does wind feel cold. The molecules are moving faster so it should feel hot. The...

Oct2712 06:19 PM
Chestermiller

5 
850 
Earlier I asked for help about a high voltage power supply, and I was told not to worry too much about 20k volts...

Oct2712 06:02 PM
harrylin

21 
1,665 
When we strike a match which is made of sulfur against a hard surface (I don't know what the surface is made of) a...

Oct2712 04:51 PM
DaTario

5 
1,091 
Hello,
I am reading through my textbook and cannot wrap this idea around my head yet
Basically, when a molecule...

Oct2712 03:27 PM
mfb

1 
732 
Can this wave in any way be considered circularly polarized?
\overrightarrow {E}\left( z,t\right) =\left E_{0}\sin...

Oct2712 01:17 PM
Qreeus

4 
777 
Hey,
during last lecture of thermodynamics we did polytropic processes, and with no
discuss teacher said, that...

Oct2712 04:39 AM
lakmus

0 
600 
Imagine Two cylinders One inside another with air in between them.There is a cutout made in the Outer cylinder.The...

Oct2712 02:50 AM
sriram123

0 
564 
In classical mechanics,
p = mv
L = Iω
These correspond to linear and angular momentum, respectively. They're...

Oct2712 12:38 AM
morrobay

5 
4,167 
So we're currently covering multipole expansion techniques in my EDM class. The multipole expansion is a summation of...

Oct2712 12:33 AM
ToothandnaiL

3 
4,433 
The Gibbs energy is used to determine the spontaneity of a thermodynamic process under isobaric conditions.
The...

Oct2612 07:30 PM
Dickfore

3 
738 
Hi, I am trying to play around with magnets on my free time, I ordered some neodyum magnets and I've been thinking of...

Oct2612 07:01 PM
_Bd_

6 
894 
Let's say I have the electric potential as a function of x, y, and z: V(x,y,z)
Now I want to find the x component...

Oct2612 05:58 PM
tinytim

1 
653 
Wavelength of a sinusoidal wave is defined as the spatial period of the wave, which can be measured between any two...

Oct2612 02:59 PM
Naty1

2 
657 
what is the literal meaning of vector product? how could two vectors perpendicular to each other form a new vector...

Oct2612 02:17 PM
BobG

7 
1,057 
I am having difficulty understanding what a state function is. Yes, I know its a function of the state of the...

Oct2612 11:17 AM
Studiot

10 
3,007 
BOUNDARY CONDITION PROBLEM
I have came up with matrix for numerical solution for a problem where chemical is...

Oct2512 05:50 PM
AlephZero

3 
736 
Hi,
I'm new to working with gratings. From using the basic grating eqn., I'm able to model the diffraction angles...

Oct2512 04:07 PM
Khashishi

3 
665 
if you have a magnet that pulls 40lbs of force if you broke that into 2 how much force will each magnet pull.
i...

Oct2512 03:59 PM
Khashishi

4 
938 
We can know about distant stars temperature,its elements etc by observing its spectra... But that star has a velocity...

Oct2512 03:54 PM
Ezio3.1415

10 
2,571 
So having been through translation and rotation I can conclude that my book has found 3 conserved quantities in...

Oct2512 09:09 AM
Studiot

6 
691 
Hello,
I'm trying to calculate the resonancefrequencies of my multilayer samples by solving the lagrangian. For...

Oct2512 08:05 AM
bck

0 
519 
Dear Physics Forums readers
Let a two dimensional rectangle R1 carry a surface charge \sigma and be placed next to...

Oct2512 06:35 AM
mzh

11 
1,040 
I am working with interference which pattern I want to magnify to a CCD. The question is how can I determine the...

Oct2512 04:35 AM
AJ Bentley

3 
478 