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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,844 
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 
394 
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 
326 
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 
240 
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 
408 
Recently, Facebook suggested solar powered drones could be used to provide internet coverage in remote areas and they...

Apr314 03:02 PM
yuiop

5 
429 
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 
334 
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 
276 
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 
298 
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 
251 
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 
557 
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 
376 
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 
209 
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 
4,684 
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 
363 
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 
347 
Hello,
Are spectral reflectance curves dependent on the interface between the reflector and surrounding medium? For...

Mar2814 11:50 AM
Andy Resnick

1 
279 
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 
237 
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 
441 
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 
1,393 
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 
524 
Im confused by a concept i have run across in Griffiths electrodynamics.
E_{out}  E_{in} =...

Mar2714 12:04 PM
vikasagartha

1 
264 
Homeopaths assert that dilution of a medicinal substance in a water alcohol mixture, followed by forceful shaking...

Mar2714 11:29 AM
Vanadium 50

3 
365 
If I needed to calculate the kinetic energy of a bar suspended by a rope at one of its ends, in other words, a bar...

Mar2714 11:28 AM
rmfw

6 
376 
Consider the Helmholtz Equations with a perturbation p(r)
u(r,w) = 0
Does anyone know where I can find resources...

Mar2714 12:44 AM
sugeet

1 
342 
Hello everyone,
I am having a little difficulty understand precisely what Gibbs free energy is. I have read in my...

Mar2714 12:25 AM
Andrew Mason

1 
270 
Hi I am pretty confused on how my book is doing the calculus of electric fields. Basically I don't understand how...

Mar2714 12:14 AM
Bashkir

1 
230 
I am currently working on my masters and happened to stumble upon screw theory, of which I have no previous experience...

Mar2614 06:49 PM
Liferider

6 
465 
Hello,
I've been making my way through LandauLifshitz's "Mechanics" book, and I've come across a bit of math I'm...

Mar2614 02:55 PM
electricspit

9 
343 
I am really loving this book. But I have come across a figure whose purpose I just don't understand. It is shown when...

Mar2614 02:53 PM
TSny

4 
485 
Let's say that we have a system of noninteracting Bosons with singleparticle energies given by,
\epsilon_{p,m} =...

Mar2614 09:55 AM
vanhees71

2 
258 
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 
5,767 