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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,911 
If for some functional ##I##, ##\delta I=0## where ##\delta## is symbol for variation functional has extremum. For...

Feb2614 01:11 PM
dauto

2 
270 
Hello
1. I was wondering why internal energy is usually expressed as a function of temperature and specific volume...

Feb2614 01:20 AM
Maylis

10 
386 
http://sploid.gizmodo.com/amazingscientistsmakethingsflyaroundinspaceusi1492880964...

Feb2514 02:45 PM
Bobbywhy

2 
279 
Is there a way to derive entropy or free energy without using partition function?

Feb2514 09:13 AM
Useful nucleus

9 
363 
How did Newton come up with
f ∝ Δp/Δt ??

Feb2514 04:57 AM
adjacent

2 
346 
Hi guys and girls,
Just had a question I have been thinking about for a while.
Suppose you have a sound maker...

Feb2514 02:52 AM
Bobbywhy

3 
261 
Ok, so in class last week, I had asked my professor about using the Lorentz Force Law to solve a particular problem. ...

Feb2414 08:51 PM
Ascendant78

3 
285 
Let’s say I have a horizontal rod whose total length = ΔXtotal = 5 inches. However, the rod is made up of two pieces...

Feb2414 06:54 PM
Simon Bridge

1 
248 
Hi,
I know that for the electric displacement vector field \oint D.dS=\sum Q_{c} does this mean that I can just use...

Feb2414 01:03 PM
Meir Achuz

1 
274 
I have a general gauss' law/electric field question.
In calculating the electric field of a cylindrical shape,...

Feb2414 12:59 PM
Meir Achuz

2 
299 
Hi fellows,
I've been looking for "High Repetitive Photocathode RF Guns" for more than a couple of days. It seems,...

Feb2414 11:03 AM
ZapperZ

6 
309 
Hi there! I have a couple of questions for you guys about Spatial Light Modulators and laser beam profile aberrations....

Feb2414 08:56 AM
Choisai

4 
333 
An electric charge produces a Coulomb electric field:
E = dqe r/r3
A current element produces a BiotSavart...

Feb2414 08:38 AM
Harrisonized

2 
250 
What will happen if two batteries were connected in parallel, and how could the total voltage and current be...

Feb2414 07:18 AM
Harrisonized

19 
651 
Hey guys, I was messing around with my guitar (classical guitar) and my amp lately. I put the treble on lowest, bass...

Feb2414 05:07 AM
sophiecentaur

4 
284 
Hi
I want to know what is the diffrences between E=σ/2ε0 & E=σ/ε0
of course I know we use the first for a very huge...

Feb2314 01:49 PM
dauto

1 
245 
consider the image on the drawing at the top (above the yellow arrow)
http://i.imgur.com/zEWCdDS.png
if i had...

Feb2314 06:20 AM
Chestermiller

3 
326 
I'll pose that as a general question, and specifically for sound waves, which Googling did not answer in a...

Feb2214 07:08 PM
mfb

3 
283 
I'm interested in modeling a system where the material varies along its length, thus the conductivity coefficient...

Feb2214 02:58 PM
j_phillips

7 
256 
I wonder if anybody can point me to a good explication of the atmospheric Coriolis effect broken down into base...

Feb2214 05:34 AM
D H

6 
366 
Hi,
And thank you for your time! :)
I've been studying and coding for more than a month on a physic engine for car...

Feb2114 11:50 PM
Deams

0 
228 
Hello
I just read this http://io9.com/scientistsjustcreatedsomeofthemostpowerfulmuscl1526957560 where they...

Feb2114 08:27 PM
Chestermiller

2 
269 
We know that gravity speeds up a body, like a meteor which enters the earth gets constantly speeded up by earth's...

Feb2114 04:43 PM
Simon Bridge

18 
1,045 
I need to find the moment of inertia of a sphere of radius ##r## and mass ##m## about an axis through it's centre....

Feb2114 02:23 PM
dauto

13 
355 
Earth has a huge angular velocity regarding its rotation. Now let's imagine that the earth has the velocity of 400...

Feb2114 08:56 AM
DaleSpam

1 
233 
I was hoping that someone could explain why these different equations can be found from different sources please.
...

Feb2114 05:36 AM
Philip Wood

5 
335 
It seems to me that for some thermodynamic variables it makes sense to talk of systems in contact with different...

Feb2114 01:45 AM
Rap

2 
286 
Hello all,
I was wondering if it was possible to have energy without an associated force. More specifically, can...

Feb2014 10:27 PM
ahyaa

3 
296 
Hi
I have been looking at canonical transformation using generating functions. I am using the Goldstein book and it...

Feb2014 09:27 PM
dyn

2 
248 
Consider a solenoid with length L and N turns of wire wound around it, filled with a rod of permeability \mu .I wanna...

Feb2014 08:35 PM
Meir Achuz

11 
619 
The Drude model of electrical conduction has the charge carriers being accelerated by an electric field and then...

Feb2014 06:07 PM
Drakkith

2 
252 
Hi all.
I'm a music student and I've been trying to educate myself about acoustics lately.
I'm exploring the...

Feb2014 01:35 AM
maajdl

1 
219 
Any idea how to work out the range of torque required to pull a 737800?
To start of with need to work out the centre...

Feb1914 02:49 PM
cjl

10 
387 
Please could somebody explain why the fundamental frequency always has the biggest amplitude in comparison to the rest...

Feb1914 02:12 PM
sophiecentaur

4 
333 
Hello!
By manipulating Maxwell's equation, with the potential vector \mathbf{A} and the Lorentz' gauge, one can...

Feb1914 01:09 PM
vanhees71

1 
382 
It is written in my book that the Electric intensity is the amount of electric charge which passes in one second. I...

Feb1914 06:48 AM
Philip Wood

13 
394 
I have always known that weight is the force of gravity. Yet I have always been confused about one thing. If you hold...

Feb1814 10:48 PM
StefanT

2 
305 
Hello!
I am wondering what supplies the energy necessary for the compression of a gas that is entrained in a flow...

Feb1814 07:41 PM
crador

4 
279 
Hello
I have a few fundamental questions about evaporation
1. In Cengel's Heat and Mass Transfer, in all sample...

Feb1814 07:37 PM
Chestermiller

24 
882 
I'm trying to evaluate floor heating systems for installation in my new studio, and I have to admit that my...

Feb1814 02:24 PM
meeotch1

3 
258 