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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,826 
My physics book says that the magnetic field is caused by moving electrical charges, acts only on charges with a...

Apr2309 05:43 PM
Bob S

7 
858 
How does Hubble Space Telescope (HST) reorient itself; and what is an underlying mathematical description?...

Apr2309 04:50 PM
mgb_phys

1 
815 
I was wondering about the problem of having a "ramp" defined as y=f(x), and a ball (or other object) beginning at...

Apr2309 10:59 AM
coddy

6 
1,182 
I am working on a ballistics model, and have been trying to find some material on impact forces. Does anyone have any...

Apr2309 09:57 AM
tuoni

0 
734 
I understand that chromatic aberrations occur because the different wavelengths of light are separated, but I don't...

Apr2309 07:50 AM
Andy Resnick

15 
2,585 
I am currently trying to get my head round RG in the context of statistical mechanics and am not succeeding! I would...

Apr2309 03:38 AM
tun

3 
770 
Dipole in an Uniform Electric Field:
torque is calculated about the position of either charge has the magnitude...

Apr2209 11:27 PM
Born2bwire

1 
1,922 
This is a conceptional problem I'm dealing with.
when no external forces act on a system momentum is conserved,...

Apr2209 11:11 PM
Dweirdo

5 
1,021 
I thought I understood this matter, but the more I think about it the more confused I am becoming.
Suppose I have a...

Apr2209 08:37 PM
snoopies622

7 
1,168 
Hi,
Im looking for a new laptop battery.
Something thats confusing me is the number of cells in a battery; what...

Apr2209 08:07 PM
swraman

3 
683 
I am looking for the simplest possible derivation of the diode equation. I need it to reference to it in my advanced...

Apr2209 06:17 PM
cabraham

5 
18,681 
I'm working with Maxwell's equations, and I have found the curl of a magnetic field at all points. How can I figure...

Apr2209 12:01 PM
Savant13

16 
1,630 
lets say i have a block of material, measures a,b,c (length width height) and two wires running in from the top, both...

Apr2109 11:19 PM
Born2bwire

2 
993 
Hello, i am trying to remember the name of the guy who created a water fountain that seemed to recycle its own water...

Apr2109 11:13 PM
russ_watters

15 
11,584 
Hi all,
I am a bit confused about the relation between the thermodynamic potentials and
the partition function....

Apr2009 12:55 PM
FranzDiCoccio

6 
1,556 
I'm doing a problem in thermodynamics that deals with sound waves and the bulk modulus B and it got me thinking. Since...

Apr2009 12:31 PM
Andy Resnick

5 
2,934 
Hello,
Could somebody help me with this equation?
The Seebeck coefficients of each material are: Selenium; ...

Apr2009 04:19 AM
matthewgill

0 
3,581 
Right, I'll try to get this question across.
Say you have 2 bar electromagnets, aligned so when you turn them on they...

Apr2009 12:03 AM
Born2bwire

1 
920 
I've been presented with these concepts, and the first time i saw them i thought they were just mathematical...

Apr1909 06:20 PM
quantoshake11

5 
3,627 
This is the paradox discussed in chapter 17 of "Feynman Lectures on Physics  Vol II"
...

Apr1909 02:13 PM
Shan Ravi

3 
2,317 
I need the Seebeck calculation explained to me:
If I have 1000 degC at one junction and 3 degC at the other, how...

Apr1909 08:39 AM
matthewgill

0 
4,304 
If you accept that the 2nd law of thermo tells you that the
Work_{net} = Q_{in}  Q_{out}
it's easy to see...

Apr1809 08:17 PM
quantoshake11

4 
911 
I'm a bit confused here with determining the tension of a rope. A very simple example will do in this case. Lets...

Apr1809 04:30 PM
gmax137

17 
10,527 
Hi Folks,
I have a quick question about the BiotSavart Law, I know what it is, but I dont know how to derive it....

Apr1809 08:47 AM
Cyosis

6 
2,120 
If an object receives heat from a heat reservoir, is it necessary for the heat receiver to release heat?
Can the...

Apr1709 07:37 PM
Mapes

13 
1,114 
The degrees of freedom associated with the possible orientations of the spins of the magnetic atoms constitute a spin...

Apr1709 06:57 PM
orthovector

3 
751 
I am currently doing experiments with polarizing optics and reflection from metal surfaces. However it's not as simple...

Apr1709 07:56 AM
Andy Resnick

3 
824 
I was reading Michio Kaku's book Prallel Worlds recently and I believe I saw it say that Maxwell's equations for...

Apr1709 04:28 AM
Phrak

7 
1,408 
Hello,
How can I measure how much torque I'm exerting on a lever?
Can it be done with a torque wrench? Or do I need...

Apr1709 04:12 AM
Phrak

6 
3,458 
Suppose \phi is a scalar function: R^n\to R, and it satisfies the Poisson equation:
\nabla^2...

Apr1609 04:06 PM
JANm

10 
3,733 
Hi ,
Please help me to solve following problem.
If 20 KJ are added to a carnot cycle at a temperature 100 degree...

Apr1609 02:46 PM
arya_jsr

5 
3,883 
Hey, first of all, I wanted to know that if you pass an electric current through an iron rod, for example, then what...

Apr1609 02:05 PM
potmobius

10 
5,094 
Hi,
As I read, A Causal signal is defined in electrical eng. context as
f(t) = \{^{f(t), t\geq{0}}_{0, t<0}
...

Apr1609 09:36 AM
Andy Resnick

5 
3,148 
Hi All  If I have a potential energy surface with two energy states, one higher than the other, where I can make the...

Apr1609 07:45 AM
DanPhysChem

1 
709 
Hi! I'm a new user of this forum, although i've been reading a few threads for a while...
Mi question is this: in...

Apr1609 06:47 AM
laharl88

5 
679 
If there's a point charge at the origin, I want to find two closed surfaces such that the flux through one of them is...

Apr1609 06:35 AM
dx

1 
619 
is it possible to convert internal energy into mechanical energy? is there some real life example which can explain...

Apr1509 09:04 PM
maverick_starstrider

2 
702 
Hey all,
First off, thks to everyone here on physicsforums, this is such a great resource for anything...

Apr1509 08:55 PM
DaleSpam

14 
1,716 
If an object slides down a slope at a constant speed is the coefficient of static friction the same as the coefficient...

Apr1509 02:26 PM
rcgldr

4 
2,102 
Consider this situation.
A nonrotating wheel is cruising through space such that its velocity vector is at some...

Apr1509 02:13 PM
rcgldr

14 
1,689 