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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,866 
I have had similar questions posted, but I am not quite sure on this one and it seems that my textbooks have trouble...

Sep2212 10:22 PM
Simon Bridge

1 
611 
This is not a homework problem, but an example that was demonstrated that I am confused about. Sorry if it should've...

Sep2212 06:22 PM
Qreeus

9 
2,450 
Hello,
I am designing a wireless energy transfer system and would like a formula to calculate the distributed...

Sep2212 03:24 PM
CWatters

1 
653 
This is a conceptual problem which I am facing for many days.
If we convert a scenario in an inertial frame into a...

Sep2212 01:21 PM
ashishsinghal

12 
1,095 
I am trying to selfstudy some physics, and have gotten a little stuck in one of Goldstein's derivations. The...

Sep2212 01:20 PM
mjordan2nd

3 
1,357 
Hi.
I have one general question and one specific question (which is related by example.)
Specific: If I am...

Sep2212 01:32 AM
Aniket1

21 
1,842 
I'm reading this pdf:
www.atm.ox.ac.uk/user/read/fluids/fluidsnotes7.pdf
(specifically equations 7.2 and 7.3 in...

Sep2112 09:45 PM
AngrySaki

0 
1,162 
So if we can one large not moving magnet and a small magnet that is attracted to the large magnet we know that (...

Sep2112 04:47 PM
mfb

11 
1,216 
hi every one :)
i need a small help please ...
we have tow frames and tow observers , let suppose there is a...

Sep2112 01:56 PM
najat

4 
1,005 
A “blackbody heat shield” is used to reduce radiant heat loss in situations where standard low conductivity insulation...

Sep2112 09:46 AM
mfb

3 
1,829 
How to derive the Rotational Inertia for a flat plate.
I do not see any symmetry about the axis of rotation as in a...

Sep2112 09:45 AM
ashishsinghal

4 
713 
I saw a baseball pitching machine that throws baseballs at 4070mph with one wheel... All that wheel does is rotate...

Sep2112 09:39 AM
ashishsinghal

2 
828 
dear all,
as a newbie in solid mechanics modelling, i always come across these few terms,
CauchyGreen strain...

Sep2112 08:11 AM
prerakchitnis

13 
6,083 
How does the first law of thermodynamics apply to the Compression And expansion of a gas at constant temperature ?
...

Sep2112 02:35 AM
Studiot

4 
928 
hi all,
im new at electromagnetics and vector calculus, so facing these trivial problems. The differential form of...

Sep2112 02:35 AM
vanhees71

16 
1,915 
the calculation of many quantities involve cross and dot products in their formulae.
For cross products, i only...

Sep2112 12:12 AM
jedishrfu

3 
924 
Hi fellow members!
I have a serious confusion for light being an electromagnetic wave? since the we know that...

Sep2012 06:35 PM
nsaspook

5 
1,112 
Hi
Not a homework question, just a fool tinkering...
I have been messing around with the concepts of a stirling...

Sep2012 01:45 PM
Andrew Mason

3 
1,489 
I was reading through Lewis Epstein's book "Thinking Physics" the other day, and I came across the problem called...

Sep2012 09:53 AM
Philip Wood

4 
1,299 
http://www.smartphysics.com/Content/Media/Images/Mechanics/06/acceleratingtruck.png
A box rests on top of a flat...

Sep2012 08:15 AM
mfb

1 
4,321 
Can someone please explain in a detailed manner about skin effect in electromagnetism, particularly wanted to know why...

Sep2012 03:10 AM
Blogical

2 
757 
C_{V} = \frac{∂U}{∂T}
This is the specific heat at constant volume so I assume it can only be used at constant...

Sep1912 08:09 PM
Chestermiller

5 
1,484 
Reading about solar panels i came across a peculiar description  "When the panel is short circuited, there is current...

Sep1912 06:08 PM
curiouschris

2 
2,010 
Hi.
Practical situation.
If I have 0.25W of constant Joule loss around a small piece of copper electric...

Sep1912 02:18 PM
mfb

3 
673 
Clever guy that I am, I am writing a small paper on Celestial Mechanics...simplified...really really simplified....

Sep1912 01:31 PM
nasu

12 
946 
Suppose in a piston in which there is a gas, the gas exerts pressure P on surroundings, whereas the surrounding exerts...

Sep1912 08:26 AM
Chestermiller

24 
7,357 
Temperature conversion:
273 + degree Celsius = Kelvin
Actually why is that 273? How does one come up with this?...

Sep1912 08:10 AM
Ken G

2 
763 
I understand the ideal gas law equation and the use of the gamma and it's relationships.
But what happens when a...

Sep1912 08:01 AM
jelanier

2 
738 
hello guys,
i need your help to clear my concept on total internal reflection ....when incident ray angle is...

Sep1912 06:37 AM
nasu

2 
1,034 
Hi! I'm trying to calculated the magnetic susceptibility of a solution. I am using this table to know what the...

Sep1912 05:13 AM
Qreeus

4 
1,103 
Maxwell equations are 8.
we need them to determine electric and magnetic field.
the component of magnetic and...

Sep1812 11:19 PM
cmos

23 
6,322 
Why is the Laplancian's Equation
\nabla^2\phi=0
right for the axisymmetric, imcompressible and inviscid flow?
I...

Sep1812 10:14 PM
Chuck88

0 
707 
In several recent threads the Poynting's theorem was brought up, and the discussion there became a distraction from...

Sep1812 05:49 PM
Darwin123

59 
7,300 
Hey guys. I'm trying to gather some tips that people have acquired that helps them write the Lagrangian for a system....

Sep1812 11:36 AM
Yondaime5685

4 
670 
Hi everybody...
I've been working a bit with models of chemical oscillators and I've run into something that isn't...

Sep1812 10:52 AM
mfb

1 
560 
Maybe someone here will have an idea where I can get some information. I am planning on making liquid nitrogen from...

Sep1812 09:48 AM
f95toli

4 
1,463 
According to the eq. U=mgh the gravitational potential energy should keep increasing with height. But it actually...

Sep1812 07:55 AM
sophiecentaur

18 
2,244 
when we tie a stone to a string and spin it,it does not seem to fall.why does it happen?i mean to say that,no matter...

Sep1812 07:09 AM
utkarsh5

5 
1,069 
I am doing a Laplace's equation in spherical coordinates and have come to a part of the problem that has the...

Sep1812 06:58 AM
vanhees71

3 
880 
Edit: I think I figured it out actually. Left must be negative by the way I introduced the xaxis meaning the force...

Sep1812 04:03 AM
mikeph

1 
617 