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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,573 
So I know there is an upper cutoff frequency (at least in the microwave band) for a rectangular waveguide. However...

Apr1408 12:00 PM
lbrits

1 
5,738 
I PM'ed the admins for the best place to ask this question, but have not heard back so:
I would like to hire...

Apr1408 11:45 AM
Zack311

0 
1,509 
This has always bugged me, and I don't think that I've ever gotten a satisfactory explanation (even though it's a...

Apr1408 06:48 AM
resolvent

13 
7,136 
All right, so, we just went over linear momentum in school, and one thing is confusing me:
If I throw something at...

Apr1308 05:25 PM
Shooting Star

11 
2,420 
Hi everybody,
I have faced with a problem in my report. The question said that "How can ferromagnetic effect change...

Apr1308 02:30 PM
slayercantona

2 
2,255 
Hi, I'm doing a question about Boyles law, and I don't understand some of the units they are giving.
Initial...

Apr1308 11:40 AM
mdnazmulh

1 
1,280 
Today I was outside to get some grass for my rabbit. I took some yellow dandelions too, but as I entered the elevator...

Apr1308 06:39 AM
Tachyonie

3 
1,570 
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 
5,578 
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 
4,400 
What are electromagnetic waves supposed to look like in 3D?
Also, in the vacuum of space, electromagnetic waves...

Apr1208 11:09 AM
lbrits

19 
5,970 
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 
1,128 
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 
4,005 
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 
1,775 
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 
2,795 
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 
3,683 
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 
4,133 
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 
1,217 
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 
1,734 
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 
2,949 
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 
2,953 
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 
1,399 
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 
2,020 
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 
1,546 
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 
4,667 
I understand very little of aerodynamics.
Currently, my high school robotics team is designing a F1 model....

Apr808 07:32 PM
russ_watters

1 
1,612 
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 
1,155 
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 
1,494 
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 
2,284 
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 
1,364 
For electromagnetic field we usually use the Lagrange's density
...

Apr708 08:24 AM
sweetser

44 
7,133 
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 
2,072 
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 
4,973 
i understand the reason and steps leading to the equation that relates acceleration in the inertial frame to...

Apr608 07:59 PM
bman!!

4 
1,439 
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 
1,415 
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 
1,537 
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 
1,001 
ive just come across gauge transformations on maxwells equations, and mathematically its all pretty straightforward,...

Apr608 01:16 AM
Phrak

5 
1,440 
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 
1,792 
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 
793 
Can an electron's mass and its magnetic moment be measured in the same experiment?

Apr508 03:57 PM
David George

2 
1,122 