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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,001 
Hello All,
I'm trying to get a sense of the cost of using electricity e.g., plugin hybrid vs. the cost of...

Jul2112 11:49 PM
OmCheeto

61 
24,550 
I have two questions/ideas about the efficiency of A/C's that I'd like to bounce off you guys. I couldn't find...

Jul2012 01:15 PM
the_emi_guy

13 
11,512 
Useless explanation text:
I'm building a shower system that uses motors to manually turn valves to adjust the...

Jul1712 11:33 PM
Valalvax

13 
4,601 
I understand the definition to be the amount of work done in moving a charge from one point to another divided by the...

Jul1812 04:38 PM
krackers

17 
2,985 
The biggest problem I'm having with Noether's theorem is that I can't seem to find it stated precisely enough...

Jul1912 05:56 AM
TobyC

14 
1,892 
Hello physics forum crew, I would like some help coming up with one of those "is this possible" type questions.
...

Jul1912 09:54 AM
Darwin123

129 
9,560 
The part of his theorem to which I am referring is the equation relating the heat & temperature for a reversible...

Jul1812 03:12 PM
Philip Wood

11 
1,502 
Does it have any deeper theoretical foundation or is it just true empirically?

Jul1812 02:05 PM
Trave11er

6 
1,032 
Consider the following theoretical cycle. There should be a flaw somewhere, but I could not find it yet and will...

Jul1912 01:37 PM
Ambforc

8 
931 
Hey guys. First off, let me say that I am in no way a science expert. I like to read about new things, and stay up on...

Jul2212 11:34 AM
MotorsportsX

12 
1,455 
Elastic scattering from a bound electron is classically described by considering the driven, damped harmonic...

Jul2112 02:34 PM
M Quack

6 
1,257 
I (and probably everyone) like to learn from books that describe the reasoning/philosophy behind the equations as much...

Jul1712 09:57 PM
sprayer_faust

2 
1,118 
This is my first post here.
I have a problem dealing with Electric flux.
According to Gauss's Law, to find...

Jul1812 10:05 AM
Quine!

2 
1,391 
Hi guys, I would like to ask how do you determine where the force is +ve or ve for this topic.
Do you follow the...

Jul1812 08:50 AM
Doc Al

1 
794 
Since the Gravitational Attractive Force is given by, F_g=(Gm_1 m_2)/r^2
Let m_1be the minor mass of a small...

Jul1812 09:22 AM
andrien

2 
1,672 
So I'm going to try to explain this as best as I can.
If you have ionized air created by the Ion Air Jet (link...

Jul1812 06:13 PM
Nessdude14

2 
1,064 
Hi,
I'm getting some confusing results and cant figure out what is wrong
Suppose we have a uniform field
E= in...

Jul1912 01:08 PM
vanhees71

3 
598 
Hi.
First post here and not a native english speaker, so be kind :)
1) I have never really understood what it...

Jul1912 03:29 AM
skywoo

2 
526 
In my course they're using the equality U = \frac{p}{\alpha \rho} with alpha some constant (U = internal energy per...

Jul1912 07:59 AM
Studiot

6 
1,232 
I was doing chapter named kinetic theory of gases from a book. here's the question.
A mercury monometer consists...

Jul1912 10:13 AM
Simon Bridge

1 
513 
Hi everyone,
This is my first post here and I am really sorry for that question, but I have found the answer...

Jul1912 02:56 PM
russ_watters

5 
653 
I have a question that's being bugging me around. This might be simple but I can't figure it out. If there's a spring...

Jul1912 08:20 PM
EBBAzores

10 
1,307 
Dear fellow physicists,
looking at the derivation for the maxwell equations into kspace, I've stumbled upon...

Jul2012 04:00 PM
PhilDSP

4 
940 
Hi everyone!
I was reading a text book a while ago about waves and it had just finished talking about wave speeds and...

Jul2012 06:47 AM
harrylin

4 
902 
How do you solve the following problem:
You are in charge of keeping the drinks cold for
a picnic. You have a...

Jul2012 04:50 AM
mfb

1 
594 
I'm doing a project for my University. Making a design for a fish friendly dam structure that will let fish pass...

Jul2212 02:48 PM
Shuff

1 
593 
I know that Young's modulus for a spring is Y= K*L/A
where K: is the stiffness of the spring
L: the...

Jul2012 09:22 PM
nasu

19 
5,508 
hi, i heard from a friend that it's possible to store light within nanoparticles, but when i asked him how he refused...

Jul2012 05:03 PM
mfb

7 
2,035 
Under what circumstances does a moving electric charge fail to produce a magnetic field?and what is the equation for...

Jul2012 02:42 PM
Darwin123

1 
634 
Hamilton's principle says that the action for the true path that a system follows will be stationary. As I understand...

Jul2012 12:53 PM
Marioeden

1 
341 
Consider a lens of diameter d and a focal length f >> d.
Let the crosssection area of the lens be S = N*λ^2.
Let a...

Jul2212 07:51 AM
htg

14 
1,333 
Hey i am working on something and i need to know how to calculate moment of inertia of a 3D system of objects.
I...

Jul2112 02:16 AM
haruspex

5 
1,564 
I have recently written a trajectory program which includes aerodynamic resistance, that is, only form drag at this...

Jul2212 06:57 AM
mfb

4 
800 
hi
i have a few questions about entropy:
why does the definition of entropy stress the fact that the heat...

Jul2212 08:43 AM
Studiot

1 
607 
Why is there no equation for solving for the magnetic field produced by multiple charges in free space? To solve for...

Jul2212 04:54 PM
Darwin123

2 
766 
Hello all!
I'm a programmer looking to put together a system modeling the force a character's limbs exert on the...

Jul2112 09:23 PM
Jellyf15h

0 
615 
Hi all,
I was having a bit difficulty understanding the term scleronomic constraint.
From what I have read, it...

Jul2112 10:16 PM
kokolovehuh

1 
1,260 
Sorry, I am not a physics major  I apologize in advance if this question is ignorant or if this was asked already.
...

Jul2212 02:19 AM
mikerand

0 
755 
Whats the fastest way of accumulating static charge on a given metal,lets say aluminium or lead?(excluding any method...

Jul2212 08:29 AM
martin f

0 
443 
which material has the highest heat capacity?

Jul2212 02:57 PM
phinds

1 
716 