Before posting anything, please review the Physics Forums Global Guidelines.
Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,832 
Obviously it has to taper from the fixed end to the most mobile one. Or from the centre (node) of a symmetrical one...

Jun1409 11:47 PM
silverslith

0 
699 
I just have some confusion about whether or not selfinductance will occur in an AC generator.
The current is...

Jun1409 10:12 PM
Yuqing

0 
1,246 
First I apologize if this has been asked before; however, did a google search of the archives and could not find...

Jun1409 08:36 PM
piareround

2 
723 
Is the second law of thermodynamics fundamental? Like Newton's laws for example.
I'm having doubts about the...

Jun1409 04:28 PM
fluidistic

18 
3,273 
In the defining the concept of "work", does it have to a defined as a force being applied to an object over a LINEAR...

Jun1409 12:41 PM
Dr.D

2 
590 
When two magnets are taped together with both north sides touching does the magnetic flux stay in its normal possition...

Jun1409 11:42 AM
wbrad320

9 
2,119 
Thought experiment: a sealed container with water in it, along with a balloon. You are able to control the balloon...

Jun1409 07:42 AM
Stan_Smith

86 
7,413 
Hi..
I´ve been trying to solve this problem for a couple of weeks and I need fresh ideas...it´s a 30 degree piece of...

Jun1309 11:56 PM
Born2bwire

3 
629 
Hi all,
Does anybody know the equations needed to predict the diffraction of electromagnetic waves by a perfectly...

Jun1309 11:52 PM
Born2bwire

7 
1,235 
Can angular momentum change into linear momentum and vice versa? For instance, when a top spins, and it stops, isn't...

Jun1309 11:07 PM
atyy

1 
1,586 
Is there a simple way to understand why the Lagrangian of the classical electrodynamic field is (in SI units)
...

Jun1309 04:11 PM
GiftOfPlasma

2 
1,228 
Hi all, this is my first post to the forum.
I've been thinking about a mechanism that can't work, but I can't...

Jun1309 12:43 PM
Doc Al

3 
743 
Hey
i m a newbie
suppose i drill a hole that passes through the centre of earth and reaches the
other point on...

Jun1309 11:46 AM
Weston

21 
2,337 
Something strange showed up while I was thinking about the following problem: I'd like to prove, by the only mean of...

Jun1309 08:55 AM
Mapes

3 
813 
The path integral of force is the work, something that has a clear physical meaning we can relate to. My question is,...

Jun1309 06:07 AM
maze

2 
1,217 
If a transformer with coil ratios 2:1 creates a voltage twice that of the primary in the secondary coil why is the...

Jun1309 12:50 AM
cabraham

1 
587 
What will be the Gravitaional force between two bodies when the distance between them is zero
e.g., If we place a...

Jun1209 07:54 PM
DaveC426913

9 
3,724 
"A 0.400kg pendulum bob passes through the lowest part of its path at a speed of 3.00 m/s.
What is the tension in...

Jun1209 07:22 PM
diazona

3 
1,215 
I'm running an experiment where I drop a mass (99.7kg) a distance of 1.8m. The load is suspended from a very rigid...

Jun1209 12:51 PM
jimbojones21

0 
1,509 
Why is breaking with the wheels turning more effective than when the wheel locks up?
Is it because there is more...

Jun1209 12:08 PM
russ_watters

9 
944 
how do we say that in a beam bending problem the bean cross section bends(rotates)around the centroidal axis. Why not...

Jun1209 08:16 AM
fdm44241

2 
2,157 
can any one give imput please,i have a problem with Youngs two slit experiment,if i remove the lens from the laser,you...

Jun1209 06:44 AM
kevinfr0st

1 
904 
In Hal Clement's classic tale "Close to Critical" the planet Tenebra has an atmospheric pressure of 800 bar, 3 gee...

Jun1209 03:49 AM
qraal

0 
493 
I need to calculate the tension on a cable. cable comes off a winch, travels up at a 45 deg angle over a pulley which...

Jun1209 12:07 AM
berkeman

3 
2,884 
Hi all,
I hope this is right place to post this question (this is not a homework question).
I wanted to find out...

Jun1109 10:30 PM
Dr.D

5 
1,760 
What is the thermodynamical reason that a car's maximum fuel efficiency is for speeds 5560 mph? (See...

Jun1109 07:48 PM
Bob S

1 
1,456 
In my radiative processes in astrophysics course I'd often see something like this:
I_\nu (\mathbf{r}, \mathbf{k},...

Jun1109 12:07 PM
cepheid

2 
673 
Hi..
I have a question about AC magnetic field, wondering if you can help me understand this.
For a DC solenoid...

Jun1109 12:00 PM
Bob S

11 
13,025 
My physics book says the angle of diffraction is approximately wavelength/length of opening (or obstacle). My...

Jun1109 11:38 AM
ranger275

0 
484 
I have some trouble understanding how changing flux produces a field. For example, I know that a changing magnetic...

Jun1109 12:12 AM
ExactlySolved

6 
3,606 
soo... this is my first post and I'd like to start out by thanking the PF people for existing and helping the resting...

Jun1009 09:05 PM
thepip3r

6 
814 
I'm trying to reconcile some concepts in electrostatics and dynamics to do with electric fields in conductors.
The...

Jun1009 05:25 AM
parsec

0 
1,643 
What is Einstein temperature? I know how to calculate it but I don't understard what it means...

Jun1009 12:52 AM
kanato

1 
1,405 
Why does fly fly? The theory based on Bernoulli's law fail to explain it since the wings of fly are flat, not curved...

Jun1009 12:42 AM
Cyrus

44 
2,700 
if an orbiting electron positron pair is moving through space with net momentum p and the 2 particles then annihilate...

Jun909 04:40 PM
benk99nenm312

48 
6,178 
Hey guys,
There is something I have known and applied for a long time, that the greater the length of an...

Jun909 02:27 PM
DrGreg

2 
773 
If you throw a baseball up on the moon, and it comes down, how is momentum conserved?

Jun909 12:08 PM
Doc Al

5 
861 
when we apply potential difference across any conductor the electric field set up in the conductor which apply force...

Jun909 11:57 AM
Bob S

6 
1,520 
Since the magnetic force on a moving charged particle is qv X B, the work done by a static magnetic field is always...

Jun909 05:41 AM
neha_dodeja

34 
6,541 
so, hey...I'm pretty new to these forums and just needed help understanding a textbook that i'm reading.
I'll...

Jun909 05:21 AM
tinytim

3 
1,845 