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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,849 
Hello PF'ers,
Why is it that two lightbulbs produce twice as much brightness as a single lightbulb would? If we...

Aug2614 08:24 AM
ViolentCorpse

4 
205 
I want to construct 5 sided dice in the shape of a squarebased pyramid.
When rolled, I want the die to have equal...

Aug2514 09:09 PM
Haborix

12 
377 
hi,
I'm a student and i have an electromagnet and a bar magnet paced head on coaxially and i want to calculate the...

Aug2514 07:16 PM
Meir Achuz

32 
846 
I cannot seem to visualize how this compression and rarefaction occurs for example when I clap my hands, I know I move...

Aug2514 07:09 PM
hongiddong

4 
201 
Hey!
I need to calculate the electric field on the axis of a circular plate of radius a with the following charge...

Aug2514 03:24 PM
loops496

2 
144 
Hello,
I am having trouble understanding collision frequency in following discussion from Kubo,...

Aug2514 08:46 AM
AirTycoon

2 
124 
Hello,
I am a PhD student in chemistry, and need to determine the pressure of a reaction to be carried out
I...

Aug2414 11:32 PM
Chestermiller

5 
200 
I am having trouble wrapping my head around the idea of a piston/cylinder type arrangement where the piston has a...

Aug2414 05:54 PM
ullrtech

7 
268 
I know that delta h(Enthalpy) is heat and it is also the total kinetic energy of the system.
Temperature is the...

Aug2414 02:13 PM
Andrew Mason

11 
414 
While deriving lagrangian equation using D'Alembert's principle, in Goldstien, they defined a variable called "virtual...

Aug2414 10:08 AM
USeptim

1 
212 
My question relates to entropy generation in a closed system
ΔS=dQrev/T for a reversible process
ΔS=dQ/T + Sgen for...

Aug2414 09:54 AM
Chestermiller

12 
259 
Just read in Taylor that in general the kinetic energy can depend on position as well as velocity. I believe him, but...

Aug2414 09:47 AM
USeptim

9 
321 
How magnetic field associate with mass........
from the experiment we know that this is due to electric charge........

Aug2414 06:39 AM
ChrisVer

3 
249 
We know that a steam power plant is basically a heat engine with steam as the working fluid.
According to the...

Aug2314 11:35 PM
Soumalya

8 
1,012 
when a magnetic field exert force on a moving charge the work done by it is 0.But bar magnet do work.And i read that...

Aug2314 04:52 PM
DaleSpam

83 
2,115 
I am not sure if this is the right forum for this question, but I arrived at the question while studying the principle...

Aug2314 03:18 AM
A.T.

9 
280 
In my theoretical mechanics class, we went over some very basic conservation laws (namely momentum) and talked about...

Aug2214 03:37 PM
Orodruin

1 
178 
Hi all,
I am preparing for my "second chance exam" in analytical mechanics.
It is a graduate course i.e. based on...

Aug2214 11:38 AM
samalkhaiat

2 
234 
Divergence of electric field is 0 for the field produced by a point charge at origin at points other than origin is 0;...

Aug2214 12:43 AM
Delta²

1 
220 
In vector form,
L=Iω.
I am trying to show that for a point particle, this reduces to L=rxp, but am getting an...

Aug2114 06:05 PM
jtbell

1 
161 
I was going through "Engineering Thermodynamics" by Cengel & Boles studying exergy analysis of a closed(non flow)...

Aug2114 01:36 PM
Soumalya

3 
198 
For a uniform, hollow cylinder, why is this derivation wrong?
M = mass of whole solid cylinder
m = mass of missing...

Aug2114 12:42 PM
BrainSalad

3 
194 
I'm given an expression for the pressure of air with height z, as
P(z)=P(0)e^{(mgz/k_bT)}
Where m is the...

Aug2114 11:09 AM
Greg Bernhardt

1 
236 
Hello Forum,
Resolution is an angular distance (measured in fractions of an 1 degree angle). The lower the...

Aug2114 09:52 AM
fog37

3 
207 
I hope this is posted in the correct thread.
When I was still in my physics class, we learned that a loop of wire...

Aug2114 02:06 AM
Simon Bridge

15 
366 
According Pascal law we get force high and low to the applying force.....why fluid not behave like ideal solid body...

Aug2114 02:02 AM
rcgldr

15 
275 
Reference to Griffith electrodynamics question: 1.16
Compute the divergence of an inverse square vector field.
...

Aug2114 12:07 AM
porcupine137

2 
182 
I have already balanced beam both side two same mass at same distance and it is pivot on its center of...

Aug2014 08:22 PM
D.R.U

7 
193 
For example, it could be said that the equation ∇*B= 0 is based on the observation that there are no magnetic...

Aug2014 03:17 PM
newton_1372

4 
268 
Hi everyone,
I am about to enter a local Science Fair and my project revolves around creating plasma in a...

Aug2014 02:29 PM
Physicist50

2 
173 
Hello,
We read very often that wave propagation électromagnetism is the result of an interaction between electric...

Aug2014 01:33 PM
USeptim

23 
406 
Good day! I am a beginner in Finite Element Analysis and Structural Mechanics. I have problem in understanding the...

Aug2014 09:01 AM
shawn

2 
161 
http://cognizantwire.net/HTMLKHSL/ELECTRON/MAGNETIC/MoveCharge.GIF...

Aug1914 07:47 PM
DaleSpam

12 
268 
Does anyone know how the mathematics/formulae of SHM (say a particle in a force field, with the standard a=d) changes...

Aug1914 05:27 PM
DaleSpam

4 
212 
Where is the glitch?
1. Let a single free electron move along x axis with constant speed Vx. It encounters magnetic...

Aug1914 04:25 PM
DaleSpam

46 
1,533 
Hello everyone,
as I know the regular precession of torquefree symmetric top is such a cliche, I'll try to keep...

Aug1914 03:01 PM
D H

13 
452 
an air wave takes place in volumes of air, water takes place in volumes of water... but u can have an electromagnetic...

Aug1914 10:57 AM
WannabeNewton

1 
186 
Please help me with this,
In Reheat Rankine cycle, we first Expand the steam partially in a high pressure turbine...

Aug1914 02:05 AM
tduell

1 
154 
I just start to read Mathematical Methods of Classical Mechanics by Arnold. And I am sort of very puzzled by all the...

Aug1814 11:40 PM
fisicist

13 
294 
When watching some videos about neodymium magnets, I came upon a very interesting phenomenon. Namely, the maker of the...

Aug1814 10:31 PM
Simon Bridge

5 
281 