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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,728 
I think the title is selfexplanatory. The first theorem states that gravitational forces (1/r potentials in general)...

Dec2013 02:53 AM
mathnerd15

8 
1,493 
Hello Forum,
potential energy is a form of energy that something has in virtue of occupying a certain position in...

Nov813 02:39 AM
codgerpool

8 
5,009 
I am doing a simple steel ball drop test on glass to see if the glass passes the standards.
We are dropping 1.18...

Mar2514 09:54 PM
Tlowe999

8 
4,656 
Suppose a cylinder is resting on a horizontal platform on plane xy with its axis parallel to the y axis, and the...

Oct613 11:56 PM
ash1262

8 
523 
I am currently trying to carry out the construction of the generalised Hamiltonian, constraints and constraint...

Oct713 01:22 PM
Bobhawke

8 
469 
I'm curious how large(dimensions) and how heavy/massive a steam(or other gas) turbine needs to be to extract a given...

Oct1213 12:04 PM
SteamKing

8 
487 
say you have spherical metal conductor with a cavity with a positive charge inside, the field inside the cavity isn't...

Oct2813 03:14 AM
mathnerd15

8 
572 
What is the criteria in choosing infinity as zero potential ?
e.g. an infinite plate with uniform charge density.
...

Oct2413 12:09 PM
rude man

8 
465 
Hello  first post to PF. I was making my iced coffee this morning as usual by pouring hot, freshly brewed coffee...

Oct2113 11:26 PM
SteamKing

8 
377 
How can you tell the difference between kinetic energy and momentum? I know KE is a scalar and momentum is a vector...

Oct3013 09:24 AM
timthereaper

8 
623 
Suppose I want to make a good acrylic lens, with very few bubbles. Could my eyes tell the difference between...

Oct3113 03:57 PM
Stargazer19385

8 
419 
I'm trying to get my head around this scenario:
http://i40.tinypic.com/2yjrmfs.png
The blocks are at rest,...

Nov913 06:49 PM
Simon Bridge

8 
642 
Hi,
I am working on a problem where my goal is to predict the location of pedestrians with certain constraints. So I...

Nov1513 01:37 PM
Jilang

8 
771 
\frac{d\textbf {r}}{dt} = \textbf {ω}
\frac{dθ}{dt} = ω
\lvert\frac{d\textbf {r}}{dt}\rvert =...

Nov1113 09:51 AM
vanhees71

8 
462 
Hello,
Imagine I have an infinite wire with a DC current. Around it there two rings of ferromagnetic material, not...

Nov2013 08:20 PM
Jano L.

8 
655 
Was reading my old copy of Surely You're Joking Mr. Feynman again; ran into the anecdote about the Feynman sprinkler....

Nov2313 02:28 PM
A.T.

8 
741 
Hi, I'm sorry if this is the wrong section. My Dad keeps telling me that light takes the path of most time elapsed...

Nov2213 11:42 AM
Vanadium 50

8 
493 
Hello. In my textbook by Jose Saletan called Classical Dynamics: A Contemporary Approach the author talks about TQ,...

Nov2913 06:18 PM
mjordan2nd

8 
358 
Why is the magnetic flux density uniform at the center of the circular loop ?

Jan214 01:51 AM
kira506

8 
389 
Hello,
F=G m1.m2/r^2
whereas g=Gm/r^2
Now, I found reading that, the Mass of Earth, radius from the center r...

Dec2313 11:28 PM
shounakbhatta

8 
493 
http://i.imgur.com/QFRCRZr.jpg (the black numbers are just so i can make references throuhout this thread, they're...

Dec2813 11:34 PM
Simon Bridge

8 
430 
Hi guys I'm having difficulty understanding why the boundary conditions lead to dX/dx = 0.
Why must Bx = 0 at x = 0...

Jan114 03:24 PM
Meir Achuz

8 
342 
If I comb my hair with a rubber comb, the comb can be used to pick up small bits of paper on a desk. This says that...

Jan314 11:43 AM
Doc Al

8 
415 
Hi,
I compute sum of energy in a cycle and I don't find 0, could you help me to find the error ? I started an...

Jan1714 07:45 AM
DaleSpam

8 
340 
I am curious how to tell how centripetal accel. changes with radius since there are two equations I can look at
a =...

Jan2014 12:39 PM
knattagh

8 
319 
Are there any realistic scenarios for which center of mass is not almost exactly equivalent to the c.o.g., i.e. they...

Jan2714 12:07 PM
BruceW

8 
357 
Consider a conducting loop with resistance R and area A suspended by a nonconducting wire in a magnetic field ...

Feb514 05:08 AM
Shyan

8 
248 
I have a disagreement with a Quantum mechanical scientist about a double slit experiment with polarizers, which gives...

Feb514 08:21 AM
DParlevliet

8 
242 
My high school teacher told me that internal forces of a system do not change the Centre of Gravity of a system. I...

Mar1414 09:01 AM
A.T.

8 
259 
Does a body rotating about an axis also rotate about any other axis?
Eg. Cars on a racetrack may be rotating about a...

Feb1014 12:31 PM
D H

8 
283 
The 2nd law of thermodynamics state that entropy increases with time and entropy is just a measure of how hard it is...

Feb1714 05:36 PM
japplepie

8 
296 
why should we use a convex lens to focus the rays at the point on the screen.why is at an angle instead of being...

Feb1614 04:39 PM
Philip Wood

8 
223 
Hello everyone,
I'm trying to find the exact velocities of three balls in the plane after they collide...

Mar714 11:26 AM
Unit

8 
336 
I would like to know if a a inductively coupled power transfer system also emits electromagnetiv waves.
The system...

Mar1314 11:20 AM
BaPF

8 
230 
If a group of point charges as a whole, has positive potential energy, what does that mean? What will happen if the...

Mar2214 03:03 PM
jonathan.15

8 
275 
To calculate the detected frequency from the source frequency, we use this formula:
{ f }_{ D }=\frac { v\pm { v...

Mar2214 06:26 PM
dauto

8 
254 
If A exerts some force on B then it experiences a force of same magnitude and in opposite direction. This didn't seem...

Mar2514 03:04 AM
Rishavutkarsh

8 
314 
Sorry, but this will be a long post.
This isn't homework, I'm reviewing physics after many years of neglect.
...

Apr714 06:00 AM
jbriggs444

8 
337 
Consider a solenoid of length l, no. of turns N, n = N/l, area A, and negligible resistance. In its middle is placed...

Apr614 04:17 PM
rude man

8 
222 
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 
285 