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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,906 
A parallelplate vacuum capacitor has 8.28 J of energy stored in it. The separation between the plates is 2.30 mm. ...

Oct308 10:02 AM
physstudent1

5 
8,685 
Hi,
When exactly does the phase change of \pi occur when a EM wave reflects from a surface? I notice that it...

Oct308 01:05 PM
Doc Al

1 
2,694 
Does anyone knows why it is impossible to obtain an odd order equation of motion from a Lagrangian? I recently heard...

Oct308 02:16 PM
lasm2000

0 
1,167 
hi. i was wondering on how to do this integral. W=  integral Pdv. what is the integral of dv ?

Oct308 02:38 PM
jasc15

2 
1,197 
p=momentum=(mass*volume)
delta px = pf  pi
mvf  mvi
mvx  (mvx) <<<< where does this second negative come...

Oct308 08:01 PM
lukasz08

3 
1,469 
If we have a system for which the Liouville's tm holds, can we automaticly say the Poincare's recurrence tm also...

Oct408 11:52 AM
Andrew Mason

1 
1,254 
Hello,
I need a calculation that can tell me how many Volts and Amperes a magnet passing through a coil will...

Oct408 01:36 PM
Type_R

1 
938 
this really is a physics question! (I think)
so, when you measure blood pressure, you wrap a cuff around the...

Oct408 06:08 PM
schroder

3 
949 
Hey,
I just wanted to clear up some confusion I've been having regarded which is which of these.
If I have the...

Oct408 06:54 PM
Antenna Guy

8 
17,037 
Hi all, my question is very basic and i am unable to digest it. Actually while explainiing the mechanism of joule...

Oct508 08:17 AM
GAGS

0 
1,422 
Is the lagrangian always K.EPE?????
I dont think so???
so WHAT REALLY is the physical significance of the...

Oct508 08:58 AM
quantumfireball

0 
955 
I think there has been floated the idea that the space elevator tether may be a ribbon. I think it will fail if it...

Oct508 02:11 PM
Topher925

2 
1,477 
Hello everyone,
if an electric field in a medium with permittivity eps_1 moves at an angle into a material with...

Oct508 02:58 PM
fisico30

0 
1,388 
Hello everyone,
a wave propagates at a speed (group of phase speed), less than the speed of light, no matter what...

Oct508 05:06 PM
Mapes

1 
2,379 
Hi, I'm in first year engineering and I have trouble understanding where this formula comes from in determining the...

Oct508 05:41 PM
Zerius

10 
833 
I know that Moseley's experience with XRay showed up the relationship between Z (atomic number) and the frequency...

Oct508 08:25 PM
squadri

0 
1,023 
Hi together
I want to calculate an electrical field between a sphere and a plate, where the sphere has a certain...

Oct508 09:27 PM
Ben Niehoff

17 
1,898 
I am currently working on a bimetallic thermometer using alumium and brass.
The coefficient of linear and...

Oct508 10:16 PM
gavin_gj

8 
7,307 
What is meant by a ray of light?

Oct608 07:59 AM
Andy Resnick

14 
4,547 
A simple question
How can one talk of a Plane Electromagnetic wave, when it moves within 3 dimensions, i.e. E and B?

Oct608 08:02 AM
Andy Resnick

1 
2,881 
I'm having a difficult time figuring out how to find length and area elements for Gauss's, Ampere's, and BiotSavart...

Oct608 03:37 PM
HallsofIvy

2 
891 
can somebody tell me all the easiest ways to generate heat, it doesnt have to be a lot but some. thanks in advance.

Oct608 04:06 PM
stewartcs

19 
1,976 
I know the formulas for efficiencies e of heat pump (it is e<=Tmax/(TmaxTmin)) and refrigerator...

Oct608 05:07 PM
russ_watters

2 
2,088 
what would the magnetic field of an infinite plane of current look like. its either zero or 1/d. I cant tell which.
...

Oct708 10:02 AM
granpa

6 
4,322 
I know very little about physics, so I hope this is a pretty easy question.
Action is always acting and reaction is...

Oct708 06:26 PM
Andrew Mason

107 
10,866 
Note: This is not a homework question. I have constructed this question to help me understand a concept.
If I have...

Oct708 07:39 PM
Doc Al

3 
2,174 
Hello everyone.
If a static charge is placed inside a metallic box, there is going to be an E field inside the...

Oct708 10:52 PM
atyy

19 
1,753 
Hey, everyone. Just a quick question here. If I have the following circuit, with it's switch initially opened, what...

Oct808 06:28 AM
DaleSpam

3 
8,915 
Hello everyone,
I would just like to know these few things, since I'm trying to build my own little variation of a...

Oct808 08:52 AM
Donny

15 
2,449 
hi..i know the faraday's electromagnetic induction e=dФ/dt...supposing there is an coil of wire and i am accelerating...

Oct808 09:21 AM
Count Iblis

20 
3,107 
http://hyperphysics.phyastr.gsu.edu/hbase/electronic/diodgate.html
Could someone please explain to me why these...

Oct808 05:47 PM
chroot

4 
1,761 
given a current loop, centered at the origin, and tilted 90 degrees so that it enters at x=1 and exits at x=1,...

Oct808 07:33 PM
Ben Niehoff

9 
2,937 
what is generator?
does it have an definition?
what is it used to do?
thanks

Oct808 08:21 PM
jomoonrain

10 
1,209 
hello, just a simple question about power dissipation in the form of heat.
If a conductor has infinite...

Oct908 07:18 AM
fisico30

5 
15,890 
In fox mcdonald  6th edition page 83...i read that the free surface profile is independent of any property of liquid....

Oct908 06:30 PM
Andy Resnick

1 
1,078 
I already took 3 quarters of EM and I'm ashamed to say I didn't learn anything the final quarter, where we covered the...

Oct908 08:31 PM
Antenna Guy

5 
2,685 
I have seen maximum work is achievable when the process is carried out reversibly. Is it correct?
For example, if...

Oct908 09:43 PM
adianadiadi

4 
2,253 
1.what are the the constants of motion of a free fall body(treat this as a onedimension motion,so there are two ...

Oct1008 04:09 AM
atyy

1 
3,753 
Faraday's law is ∫ E dl =  ∂Ф/∂t
if we take sqaure root on both sides,
√∫ E dl = √ ∂Ф/∂t
√∫ E dl = i √ ∂Ф/∂t
...

Oct1008 02:57 PM
ArjenDijksman

14 
1,644 
Can you measure a force?

Oct1008 04:32 PM
russ_watters

6 
1,374 