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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,791 
Suppose I have a charge inside a conductor as shown in the image I've attached. For any charge distribution: \oint...

Jan1314 07:48 PM
phy_infinite

4 
386 
If all the currents were inside a sphere with the radius R, then we would have \int B \,dV= 2/3\mu_0 M where M is...

Jan1314 06:45 PM
Simon Bridge

1 
277 
When rolling on a flat floor when the velocity at the circumference equals the velocity at the centre of mass the...

Jan1314 03:39 PM
tinytim

1 
298 
Hello,
I'm trying to prove a simulation of mine is working correctly. the simulation has a cube of sides 1, mass 1...

Jan1314 03:29 PM
facenian

2 
348 
Hi there,
I am reading about Lagrangian mechanics.
At some point the difference between the temporal derivative of...

Jan1314 11:12 AM
voko

5 
330 
I've got a few issues with the topic of thermodynamic expansion, ΔU, etc.
With ΔU=q+w, this w is to mean work done...

Jan1314 06:37 AM
Chestermiller

23 
941 
hello, I would like to hear some comments about this situation. There seems to be two incompatible definitions...

Jan1214 08:06 PM
Simon Bridge

10 
661 
Hall showed that a slightly higher exponent in Newton's equation would cause precession. Would there be the same...

Jan1214 05:31 PM
Shaw

0 
212 
A high Q antenna basically means the antenna stores a large amount of energy in the near fields compared with the...

Jan1214 03:21 PM
Spinnor

0 
313 
Hellow!
A general system massdamperspring is describied by differential equation:
m \frac{d^2x}{dt^2}+\gamma...

Jan1214 10:47 AM
tinytim

1 
381 
The Law of Conservation of Momentum states that the total linear momentum does not change in any closed system not...

Jan1214 10:45 AM
oneplusone

2 
359 
Hi all! I am hoping your combined brains can help me with a problem in analyzing a technical rope rescue system I have...

Jan1214 09:37 AM
CWatters

11 
480 
Object with positive mechanical energy in an attractive force field moves along a hyperbolic path and whose energy is...

Jan1214 04:09 AM
AbhiFromXtraZ

11 
514 
If I have a spinning circular disc of uniform density, how would I find the torque generated by friction, if the disc...

Jan1214 01:03 AM
Simon Bridge

3 
351 
This isn't homework. I'm reviewing physics after many years of neglect. As with most of my posts, I made this problem...

Jan1114 08:16 PM
inkliing

2 
315 
I am working on a problem involving force between two loops of current. The problem is to prove the for any arbitrary...

Jan1114 05:24 PM
DaleSpam

6 
824 
Hall showed that a slight increase in the radius exponent in Newton's equation would cause precession. What would the...

Jan1114 04:53 PM
Shaw

2 
329 
So i was wondering how the curl of the magnetic field is derived since Feynman just introduces it from nothing in his...

Jan1114 05:34 AM
dextercioby

1 
249 
Hello,
I am trying to find the heat capacity ratio of water at 1000C or 1273.15K.
I have tried to find it through...

Jan1014 07:26 PM
dbmorpher

4 
261 
In wikipedia it says that "Coulomb's law of electric forces was initially also formulated as instantaneous action at a...

Jan1014 05:53 PM
mfb

1 
323 
According to "Physics for Engineers and Scientists by Ohanian and Markert, a second is the time needed for...

Jan1014 03:59 PM
Nugatory

2 
345 
Please help. Ice is more denser than water when temperature of water ≥9°C. Then why ice doesn't sink in water at these...

Jan1014 02:31 PM
pscience

13 
487 
I have a classroom full of Ohaus centogram model 311. Most work fine, but a few I can't calibrate to 0. I've used...

Jan1014 02:06 PM
AlephZero

4 
238 
In Griffith's section about electrostatic boundary conditions, he says that given a surface with charge density ...

Jan1014 10:50 AM
phy_infinite

7 
314 
I understand that the torque caused by the friction must cause an angular acceleration, and it makes sense that the...

Jan1014 08:07 AM
Tanya Sharma

1 
285 
Angular momentum is conserved, which means that the change in angular momentum of object A must be exactly canceled by...

Jan914 03:35 PM
BrainSalad

3 
316 
Hello everyone,
Here is something I've discussed with some colleagues recently and that generated a lot of...

Jan914 10:50 AM
DaTario

25 
909 
What exactly is phase space and how is it different from real space i.e. 3 coordinate system?
what does it mean when...

Jan914 10:08 AM
Chestermiller

11 
404 
Electric field of an electromagnetic wave incident on a metal accelerates free electrons, and these accelerating...

Jan814 06:13 PM
sophiecentaur

28 
935 
For several years i have thought about air (fluid) resistance without getting deeper into the formulas that model its...

Jan814 05:14 PM
A.T.

1 
370 
on a soap bubble colours can be seen.my text book says its due to the interference betwewn light waves from the top...

Jan814 03:31 PM
sophiecentaur

2 
282 
Hi,
I have problem understanding some things about this particular LDV system(a Laser Dopler velocimeter).
...

Jan814 11:30 AM
Drakkith

1 
256 
Hi, so i have a fairly good understanding of most of the concepts relating to inertia. but my question is what is the...

Jan814 10:46 AM
CWatters

4 
409 
Hi all
First time poster, long time physics lover. ;)
My dad and I got into a discussion the other day since...

Jan814 04:11 AM
sophiecentaur

9 
5,147 
I have been reading Lagrangian from Classical Mechanics by John R. Taylor.
I have adoubt in a derivation which...

Jan814 03:21 AM
darwined

2 
317 
Hello.
I'm wondering about the Gaunt factor.
I'm currently interesting in the spectroscopy in which the Gaunt...

Jan714 07:17 PM
goodphy

0 
323 
Suppose the particle is at distance x from mean position and moving away . The standard formula for calculating...

Jan714 05:13 PM
sophiecentaur

29 
899 
This is driving me nuts. What am I missing?
Suppose you have an inclined plane with a mass m resting on it. The...

Jan614 06:42 PM
rexregisanimi

2 
332 
Hi, please could someone help clarify the reason why a mechanical wave is inverted at a boundary as I'm really stuck!...

Jan614 05:44 PM
sophiecentaur

3 
376 
the question is about the uniqueness theorem (right now I am reading in griffiths book).
the first uniqueness theorem...

Jan614 05:40 PM
Simon Bridge

10 
440 