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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,811 
Dear All
I have a problem that can be represented in two different forms.
Problem is related to propagation of waves...

Apr1308 04:31 AM
tinytim

3 
5,466 
surely \vec{\nabla} \times \vec{B} \neq 0 in general
but the work done by magnetic field on any charge is 0 hence is...

Apr1208 02:33 PM
genneth

6 
4,078 
What are electromagnetic waves supposed to look like in 3D?
Also, in the vacuum of space, electromagnetic waves...

Apr1208 11:09 AM
lbrits

19 
5,697 
Hi,
I have this question. If a diode were connected to a circuit with an alternating current and there was a...

Apr1208 06:35 AM
Icetray

1 
1,083 
In practice, the suspension system of a car consists of a spring under compression
combined with a shock absorber...

Apr1208 04:10 AM
tinytim

6 
3,808 
Hi guys,
In quantum mechanics, the virial theorem for a system in its ground state is proved by a very nice scaling...

Apr1108 03:48 PM
luben

1 
1,682 
Suppose I have 2 bodies, M1 and M2. Assuming that no other forces are acting on them aside from gravity, what is the...

Apr1108 11:34 AM
Ulysees

3 
2,729 
According to Bernoulli's law pressure and velocity along a stream line are related to each other.
What is the most...

Apr1108 06:25 AM
Astronuc

7 
3,596 
hello all,
I got a bit of a problem. I want to calculate the vapor density (kg/ m3 or lbs/ ft3) with the following...

Apr1108 01:46 AM
timvk

3 
4,043 
then that object would vaporize or cause a nuclear explosion. Atoms crashing into an object at the speed of light...

Apr1008 11:58 PM
Feldoh

4 
1,180 
Greetings,
Regarding a mass on a spring – I know the classic differential equation is
m \frac {dx^2(t)}{dt^2}...

Apr1008 03:32 PM
Sparky_

9 
1,671 
If two different masses, separated by a spring, are pulled apart, and then the spring is instantaneously release from...

Apr908 06:51 PM
grabbinghands

6 
2,864 
If a string is attached to a weight and swung around overhead, is the force that creates tension on the string...

Apr908 06:37 PM
DaveC426913

18 
2,813 
Can somebody please shed a little light on what this formula represents in the physical world?
And how could I solve...

Apr908 03:20 PM
hslilly

4 
1,302 
it states that in a given volume V surrounded by conductors or for that matter infinity if the charge density \rho and...

Apr908 08:02 AM
pam

5 
1,964 
Hi, nice to find a physics forum. I had a quick question.
I'm a television producer and developer, primarily in...

Apr908 07:25 AM
Shooting Star

1 
1,469 
An object rolls down a smooth plane (whose angle and length are given) starting from rest. At the end of the plane it...

Apr908 05:24 AM
Hootenanny

7 
4,469 
I understand very little of aerodynamics.
Currently, my high school robotics team is designing a F1 model....

Apr808 07:32 PM
russ_watters

1 
1,520 
I started having this doubt since i saw the derivation of potential across a capacitor using this method. So.. here i...

Apr808 03:12 PM
Shooting Star

4 
1,100 
My lecturer has given me this formula for reflective diffraction
m landa = d (cos a  cos b)
where
m is...

Apr808 02:11 PM
neu

1 
1,438 
Its been 15+ years since I have done any calcs like this and am very rusty, so even just a pointer in the right...

Apr808 12:25 PM
Gordianus

1 
2,202 
From the 1st law of thermodynamics we have
dU = ∂Q+∂W
but we also know
dU = Tds  pdv ,
i am confused...

Apr808 07:48 AM
Hootenanny

1 
1,197 
For electromagnetic field we usually use the Lagrange's density
...

Apr708 08:24 AM
sweetser

44 
6,856 
Does anyone have an idea about a formula relating the refractive index of a medium
to the temperature gradient...

Apr708 01:43 AM
Relena

7 
1,971 
Anyway ... a long long time ago, my father told me a story how when he was in college, they used to heat water just by...

Apr708 12:39 AM
Shooting Star

6 
4,681 
i understand the reason and steps leading to the equation that relates acceleration in the inertial frame to...

Apr608 07:59 PM
bman!!

4 
1,396 
I raised this question in the courseware section and I got only one response. To improve the response, I am repeating...

Apr608 06:28 PM
Doc Al

1 
1,376 
I'm trying to explain to a coworker some fallacies in a thought problem he came up with that has severely confused him...

Apr608 02:56 PM
luben

9 
1,494 
hi
I'm a new poster here.the three body problem fascinates me a lot and was just wondering if there's any book out...

Apr608 09:56 AM
Jacob1983

0 
971 
ive just come across gauge transformations on maxwells equations, and mathematically its all pretty straightforward,...

Apr608 01:16 AM
Phrak

5 
1,360 
How does a magnetic field do work on the electrons in a wire?
If F = q v x B, the magnetic field is always...

Apr508 10:36 PM
Phrak

7 
1,654 
Hiya. I'm revising for a classical mechanics first year exam, and the lecture notes on central forces are less then...

Apr508 04:35 PM
cpfoxhunt

0 
764 
Can an electron's mass and its magnetic moment be measured in the same experiment?

Apr508 03:57 PM
David George

2 
1,073 
I would like to analyze the motion of a superball, heres what I have so far, the perpendicular(to the ground)...

Apr508 01:45 PM
SpitfireAce

0 
1,127 
As we know, the variational principle can be used as the fundamental principle of mechanics. Without knowing Newton's...

Apr408 08:18 PM
cstalg

4 
2,794 
Consider a wire, if I suddenly pass current on it. There would be an instant localized B field around the wire. Since...

Apr408 07:58 PM
enroger

4 
919 
In school yesterday I was doing a practical and when I moved a small 1.5T block magnet near a rheostat the magnet...

Apr408 05:21 PM
lugita15

1 
1,190 
Im studying for the Fundamentals of Engineering exam (coming up April 12!!) and came across this Thermodynamics...

Apr408 01:04 PM
Mapes

1 
1,015 
I wanna know if in rapid adiabatic compression of a gas, is work done by gas on surrounding (atmosphere) numerically...

Apr308 11:07 PM
zarbanx

14 
2,815 
Hi all,
One idle night a friend and I started an argument over the question:
"How much energy is imparted on to...

Apr308 06:06 PM
seycyrus

12 
7,911 