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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,892 
http://www.physicsforums.com/attachment.php?attachmentid=67782&stc=1&d=1395173030
Consider the following setup (see...

Apr614 01:26 PM
DaleSpam

54 
1,792 
Greetings,
I fell upon a certain question and it seemed that no matter what I did I was unable to solve it. I wished...

Apr614 10:08 AM
nasu

11 
401 
Given a system's Lagrangian, How can we calculate the equilibrium points corresponding to the system? also how can we...

Apr614 08:12 AM
dauto

1 
189 
Greetings,
I was thinking about bouncing a tennis ball against a wall and how its momentum and kinetic energy would...

Apr614 02:10 AM
drichard

4 
197 
Hi, does somebody know a good website with many exercises about Lagrangian/Hamiltonian mechanics? And I mean problems...

Apr614 01:47 AM
UltrafastPED

1 
214 
Suppose we have two colinear strings under tension, attached far away, and with propagation speed v. Let the strings...

Apr514 03:38 PM
Spinnor

0 
249 
As I understand it, The intensity and extensive thermodynamic system parameters can only be internal parameters. The...

Apr514 01:38 PM
yuiop

6 
380 
I was following along in my Thermodynamic textbook and began playing with some definitions. In the following...

Apr514 07:24 AM
UltrafastPED

1 
207 
Hi
I am using Simple Harmonic Motion in a Matlab/Simulink model. Instead of using a motion for a simple pendulum, I...

Apr514 04:09 AM
T2theB

1 
286 
Momentum of a body can be constant while it accelerates? I mean if velocity increases while mass decreases...

Apr514 01:36 AM
Michael_25

8 
381 
(This is not a homework problem, but is just something I'm curious about.)
If two rocks with different momentum...

Apr414 10:48 PM
cjl

16 
399 
So if I slowly pull the A string first B string will tear apart... Cause the A string will expand and it will pull the...

Apr414 05:31 PM
Ezio3.1415

2 
199 
Hello,
I'm trying to make my own physics engine. I've already made one with momentum and an very easy
collision...

Apr414 01:11 PM
craigi

5 
397 
Hi
I have calculated angular acceleration which changes with time. I also have a moment(torque) which also changes...

Apr414 09:36 AM
james6008

4 
329 
A homogene rod with length "l" is placed vertically, and a nail is stabbed on the top of the rod (now the rod has an...

Apr414 06:43 AM
Andreas

0 
241 
I have just watched a MythBusters episode investigating whether a concrete glider could fly. They conclude that it was...

Apr414 02:29 AM
A.T.

14 
413 
Recently, Facebook suggested solar powered drones could be used to provide internet coverage in remote areas and they...

Apr314 03:02 PM
yuiop

5 
431 
EDIT : solved, thanks :)

Apr314 08:57 AM
CWatters

1 
171 
Is it possible for a magnetostatic field to exhibit vector circulation when no current ( free, bound or polarization )...

Apr314 12:58 AM
UltrafastPED

6 
336 
hey pf!
so i have a small question when deriving the navierstokes equations from newton's 2nd law. specifically,...

Apr214 11:06 PM
joshmccraney

6 
279 
Hi,
I need help with the following equations.
n = r/r (unit vector in r direction)
v =d r/dt = dr/dt n +...

Apr214 07:03 AM
knockout_artist

4 
299 
If you stop cooling a resistor and stop current simultaneously then what happens to the temperature of the resistor in...

Apr214 03:05 AM
256bits

2 
252 
I'm wanting to get the time it would take a vehicle to travel a 1/4 mile coming out of a corner in the ideal world. By...

Apr114 06:06 PM
RedRook

17 
559 
I am trying to use thermodynamics manipulations in order to find \partialP/\partialV (at constant entropy) I tried...

Apr114 04:35 PM
rude man

1 
244 
I am doing a final year project, my Prof gave me 2 prism.
He wants me to do so:
A white laser is shot on a prism...

Mar3114 10:18 AM
athrun200

5 
301 
If I have a pair of coils connected in an antihelmholtz configuration, with current flowing oppositely in both, and I...

Mar3114 09:49 AM
UltrafastPED

16 
378 
On the 2012 AP Physics C Mechanics test, I got confused by the sign conventions for torques on question 3....

Mar3014 11:59 PM
Simon Bridge

1 
231 
I was wondering where the derivation of the formula
Group Velocity = Phase Velocity + K(dVp/dK)

Mar3014 01:55 PM
UltrafastPED

1 
206 
What happens To the force between 2 charges if a metal sheet or a dielectric sheet is kept in between the two charges...

Mar3014 01:52 PM
UltrafastPED

1 
210 
suppose a solenoid has N turns
What is the Flux through the Solenoid?
similarly if a coil has N turns , what is...

Mar3014 08:25 AM
K Dhiraj Bhak

2 
250 
How can I figure out how to calculate the heat/cooling exchange rate of water inside pex tubing? I want to build a...

Mar2914 08:11 PM
Equinefencer

18 
4,700 
Hello,
Question is about equation 5.71 to5.72
All that was done is algebra or trigonometry?
Where do I...

Mar2914 04:22 PM
knockout_artist

5 
472 
Hello,
I'm currently working on simulations in Solidworks of the flow of air (v = 450 m/s)
around a sphere (radius...

Mar2914 03:48 PM
boneh3ad

1 
232 
The period of a satellite revolving around the earth earth at surface height is equal to the period of any mass thrown...

Mar2914 07:26 AM
Ezio3.1415

3 
364 
First post here. This question has two parts. (1) Connecting the dots between the ImpulseMomentum Theorem and the Law...

Mar2914 02:16 AM
jstad

2 
348 
Hello,
Are spectral reflectance curves dependent on the interface between the reflector and surrounding medium? For...

Mar2814 11:50 AM
Andy Resnick

1 
280 
Recently I am reading the papers in the field of PT symmetry systems. What I am confused is that in these papers,...

Mar2814 02:16 AM
UltrafastPED

1 
238 
On page 122 of Born and Wolf's "Principles of Optics" the following equation for the trajectory of a ray of light is...

Mar2814 12:45 AM
PhilDSP

6 
446 
I'm trying to understand why a superdeformed nucleus may be represented as bulging perpendicular to the axis of...

Mar2714 11:05 PM
D H

40 
1,402 
I'm having a hard time understanding why the electric potential halfway between two equal but opposite charges is 0....

Mar2714 09:23 PM
ZapperZ

6 
532 