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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,680 
Hi, the title above is a specific instance of a more general question. I'm basically wondering why the atoms in a wall...

Jul1409 07:48 AM
anant25121986

5 
13,350 
Can anyone provide a brief explanation what an EM mode is? I've read some EM theory, but still have problems...

Jul1409 03:56 AM
Born2bwire

1 
702 
I've been following along with Lenny Susskinds lectures on modern classical mechanics on youtube.
at 34:30 he...

Jul1409 02:38 AM
adkinje

2 
1,193 
I was going through wikipedia and other online 'resource' sites trying to to find an answer to this question, and the...

Jul1309 09:04 PM
Bob S

6 
1,683 
If we launch a satellite to a circular orbit around the Earth at height 357.1 km, to find the velocity needed at...

Jul1309 07:48 PM
Bob S

5 
1,152 
Let's say we have an electric field,
(ax, 0, 0). (a is a constant)
The divergence of the field is a, so the...

Jul1309 03:22 PM
clem

4 
5,661 
What is a general definition of temperature that can be applied to an arbitrary system?
My best guess so far was:...

Jul1309 01:21 PM
Gerenuk

10 
1,578 
Imagine that you have N points scattered in the plane. Each point is charged and contributes to the total potential...

Jul1309 11:01 AM
woertgner

2 
552 
Can any one tell me what the velocity of air coming out a valve of a tyre pumped to 200 kPa would be?
What...

Jul1309 09:26 AM
FredGarvin

8 
744 
When you increase the charge Q on a capacitor, why don't you increase voltage V across it as well? Wouldn't higher Q...

Jul1309 08:39 AM
Dadface

5 
2,354 
obviously the rootmeanssquare speed value is greater than the average value.
Question is to why the...

Jul1309 08:19 AM
cipher42

2 
10,122 
I was discussing this with a friend:
Say you are doing a tailwhip on a bike (bike spins around pivot at headtube)
...

Jul1309 04:41 AM
joshd

2 
669 
If it takes 10 min to hard boil 1 egg, how long will it take to boil 2?

Jul1309 12:50 AM
pixel01

24 
1,698 
In what condition is the acceleration of a falling parachute is zero?

Jul1209 09:42 AM
vin300

8 
658 
Disclaimer: English is not my native language. I'll try to do my best, but i could put some inappropriate term...

Jul1209 09:40 AM
Kibuzo

2 
1,178 
There's something I struggle to understand.
In the picture I attached to this post , the first drawing is a system...

Jul1209 07:20 AM
Pnume

2 
701 
The following came from a discussion about launching a balloon.
Suppose you have a heavy coiled rope of total...

Jul1109 08:52 PM
PeterPumpkin

8 
1,253 
I know that we can find the speed of the wave in shallow water by:
c^2 = gh
but how do we derive it?

Jul1109 05:55 AM
poilop

2 
4,317 
please can you lookm at my video on youtube and give comment,if you think im mad say so,if you think it looks right...

Jul1009 11:58 PM
Born2bwire

5 
1,708 
Pseudo forses arising in a frame are defined as the negative of mass times acceleration of the frame used. now in...

Jul1009 05:12 PM
tinytim

2 
865 
Theres this retard on another forum preaching that matter travels as waves. And that he once calculated the amplitude...

Jul1009 04:45 PM
turin

18 
1,603 
Here's the good explanation.

A surface is an abstract mathematical tool that we can use to explore...

Jul1009 04:27 PM
turin

1 
526 
I saw a teacher today with a piece of chalk tied to the end of a string (for drawing circles and such on a chalk...

Jul1009 02:52 PM
rcgldr

5 
970 
Hi,
What is a good interpretation of electric permittivity? If you look at Coulomb's law, it seems that the...

Jul1009 10:57 AM
rockyshephear

3 
11,744 
I was a bit surprised to find that the average recorded atmospheric pressures at such locations as Mexico City (2.2 km...

Jul909 11:19 AM
Bob S

24 
15,413 
There are situations when a water drop falls on a really hot metal surface and, instead of evaporating, it kinda...

Jul909 08:22 AM
Edi

2 
2,131 
Hi There
Can some one please help me find a table or chart that has accurate data for water pressures and...

Jul909 07:42 AM
Paul245

1 
4,957 
I have a few extremely simple questions about thermodynamics... I'm trying to self study it, but a few things just...

Jul909 05:30 AM
jmb

5 
1,056 
I am working on a research project in which i need to create a uniform electric field inside of a tube. I am using a...

Jul909 05:25 AM
qais97

2 
5,338 
Consider a case where 2 people are in a car driving in a straight line at sufficient speed. At some point the driver...

Jul909 05:20 AM
vin300

8 
1,373 
How do you calculate amount of power needed to slowly rotate shaft under bending moment? This is not related to...

Jul809 11:59 PM
vin300

1 
2,464 
If you have a certain number of particles such as a few electrons and protons in an area, how would you determine the...

Jul809 11:09 PM
dE_logics

2 
588 
Hi!
I'm interested on how a 45gallon drum (filled with air) behaves when submerged in water. I did some...

Jul809 10:38 PM
hodderman

9 
4,812 
Can anyone help explain how to convert velocities to different co ordinate systems? I've always been shocking at...

Jul809 10:33 PM
DaleSpam

8 
11,139 
Tell me what makes electron have a charge , what is that property of electron due to which there is attraction...

Jul809 04:30 PM
mathman

5 
697 
Hi all.
Could anybody please advise me some good books on Thermodynamics to begin with? My current level of Physics...

Jul809 03:25 PM
Pinu7

1 
1,062 
Does anyone know how to derive the following:
\nabla x \vec{V} = k...

Jul809 02:39 PM
jeff1evesque

0 
551 
Consider a toroidal solenoid powered by a sinusoidal voltage. This will lead to appearance of sourceless electric...

Jul809 09:12 AM
ZapperZ

6 
1,035 
My specialization is Mechanical engineering. So I'm dumb to many of the electromagnetic concepts. But right now, I...

Jul809 08:11 AM
Andy Resnick

9 
2,352 
is there any one who wants to chat about it ? iv tried once here and got not 1 reply,
not even the YOU HAVE DONE IT...

Jul809 07:39 AM
Dadface

1 
669 