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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,893 
Everyone here should be familiar with the office toy known as Newton's Cradle where a ball collides with a group of...

Jan1310 10:11 PM
Prologue

8 
10,178 
I am trying to understand how the concept of moment was introduced in physics. For example I don't understand how the...

Jan910 05:21 AM
tinytim

7 
4,051 
Hi
I am trying to work through the solution to the attached problem (see attachments). Now, I can't understand...

Jan810 05:43 PM
vertices

17 
2,457 
Dear all,
As I understand the venturi effect, if a flow of water passes through a constriction, its velocity...

Jan1310 01:38 PM
amrbekhit

1 
15,595 
Hi. There is just this one thing in mechanics which is lagrangian that I just simply can't grasp physically. I'm...

Jan910 02:43 PM
fluidistic

13 
1,037 
I have a motor I wish to evaluate.
I wish to measure the Joules input and output.
I believe I am making several...

Jan1010 05:16 AM
nickec

5 
1,414 
In general what does a Lagrangian for a system consisting of interacting fields and particles look like?
It can't...

Jan910 09:26 AM
pellman

1 
740 
I understand why a heavy item and a light item both fall a given distance in the same time  in a vacuum, etc.
What...

Jan1110 06:58 AM
Gerenuk

3 
1,012 
Looked at Maxwell's eqns after quite some time,and was wondering, what happens if we apply an alternating flux to a...

Jan1010 11:05 AM
GRDixon

4 
2,081 
Gentlemen,
I am a retired (after 35 plus years) secondary, college art teacher. For the last eight years I have...

Jan1010 02:27 AM
Danger

13 
6,611 
Hi.
I'm beginning to study thermodynamics. I'm told that an adiabatic process is a process that is thermally...

Jan1110 08:40 AM
DocZaius

12 
2,167 
Hello everyone.
Que: Is there a reason for water flowing from a faucet to be narrower at the bottom then the top??...

Jan1010 11:26 AM
Prologue

4 
902 
Consider that we have ice and water together ( no heat exchange with surrounding ) and
qi1 = heat required by ice to...

Jan910 06:13 AM
HallsofIvy

1 
1,082 
is the distance between electrons in an electron beam constant

Jan910 07:07 AM
ZapperZ

1 
639 
Hello
Does anyone know where can I find a derivation (or approximation) for Huygens principle from more "basic"...

Jan1210 02:01 AM
Claude Bile

7 
1,805 
I'm setting up an experiment where I have a circular cathode releasing electrons to an outer circular anode. The tube...

Jan1010 03:46 PM
Bob S

6 
2,765 
first off, sorry if this isn't the correct section for this question
maybe if it's not, someone could move it to a...

Jan910 04:57 PM
freenode5

0 
942 
I know this is getting really ridiculous but I have yet another question on Lagrangians...
This is our Lagrangian:...

Jan1210 01:13 AM
diazona

5 
1,040 
Hi. I'm a student in AP Physics this year and we started the E&M portion this week and we learned about electric...

Jan1010 04:23 PM
Durin

6 
2,997 
(Sorry for my poor English, Please, forgive mistakes, if any.)
Dear Friends
Not doubts about what is to be meant...

Jan1110 07:51 AM
BarbaraDav

5 
1,261 
Let's assume that electron is moving around the unit circle. Using Maxwell equations show what is the frequency of...

Jan1110 10:07 AM
GRDixon

6 
661 
Please see the attachment. There I have derived Kirchhoff's Voltage law from Faraday's Induction law. Reply me if I...

Jan1110 09:53 AM
emroz92

4 
1,167 
If we have a Lagrangian which looks like this:
L=\frac{m}{2}g_{ij}(x)\dot{x}^i\dot{x}^j
where:
...

Jan1110 12:41 AM
Prologue

5 
871 
I have an electrode that I'm trying to model. It's got v=0 at z=0, and v=V at z=H. I've been playing around with the...

Jan1210 06:19 AM
clem

2 
1,748 
If a force is applied to an object, will the object always experience the same linear momentum change regardless of...

Jan1110 07:35 PM
Gerenuk

9 
4,251 
If Light is EM wave, and antenna can emit EM wave, then can an antenna emit light? Is this a matter of designing the...

Jan1110 12:19 AM
saltine

2 
806 
Say you have a charge distribution in the picture, and you want to find the potential THEN the electric field at P,...

Jan1110 07:52 AM
Identity

4 
792 
Setup
Closed tube with a hole at each end. Microphone at one end attached to computer. Clap noise made at the other...

Jan1210 05:23 AM
Stonebridge

1 
2,464 
I'm interested in calculating the capacitive current when the electric field across a capacitor is given by a random...

Jan1110 05:36 PM
berkeman

3 
2,907 
inertia is the state of an object at rest and a body in motion will move at constant velocity unless influenced by an...

Jan1210 03:16 PM
GRDixon

3 
910 
If you have a sphere of metal electrically isolated by a vacuum, and continuously add negative charge to it, the metal...

Jan1110 09:24 PM
Born2bwire

1 
901 
(Sorry for my poor English, Please, forgive mistakes, if any.)
Dear Friends
A system of second order, in normal...

Jan1210 08:40 AM
BarbaraDav

0 
1,151 
When an apple falls to the ground does it not exert some gravity of it's own on the earth and thus shortening the...

Jan1210 11:04 AM
mtasquared

3 
647 
I asked my professor, but he had no idea. Not really important, I guess, but I'd like to know.

Jan1210 10:36 AM
supijt

0 
3,097 
Hi.
I differentiated the equation of kinetic energy
E(v) = \tfrac{1}{2} mv^2
and I got:
E'(v) = mv.

Jan1210 04:04 PM
GRDixon

8 
8,382 
Hi, I understand that a conservative force cannot depend on velocity, because by changing velocity we can do different...

Jan1310 01:24 PM
Gaudium

2 
627 
In the attachment, I have tried to bring out Doppler effect a bit differently than our normal textbooks. Please see...

Jan1310 01:45 PM
emroz92

0 
830 
I have to design a small aerator in the middle of a larger project . Therefore I need to have some design equations. ...

Jan1310 02:21 PM
Derulz

0 
591 
Hi Everyone,
I'm trying to find the eigenfunctions and eigenvalues for a quantum spinless particle within two...

Jan1310 07:21 PM
aurelio

0 
732 
i am now reading the book by goldstein on classical mechanics
classical mechanics is always a difficult subject for...

Jan1410 04:03 AM
wdlang

0 
746 