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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,699 
i want to know about the denisity of air and how does it exchange .... to use it in equation ....and the denisity of...

Feb2209 12:58 PM
pallidin

2 
840 
Could someone explain the connection between density, pressure, and temperature in relation to the ideal gas law to...

Jun1811 06:02 PM
my_wan

2 
1,658 
Question: Show that for a steady flow with div.u=0, the density is constant along streamlines.
I just don't see...

Jan2911 04:20 PM
jmz34

10 
2,429 
Let pressure equation of sound wave be
\Deltap=Pocos(\omegatkx), then
what will be the density equation of the...

Jan2310 02:13 PM
abhineetK

2 
1,104 
Should be a simple question really can not understand why I am not able to get my head around it though. Assume an...

Jun109 10:16 AM
ponjavic

0 
1,367 
I would like to know if density is exactly the same everywhere in a disk full of water except at one part where there...

Oct3013 04:30 AM
Borek

3 
353 
what do the nondiagonal components of a density matrix tell us about the mixed state we are in?

Apr1710 08:25 AM
Andy Resnick

1 
791 
I came across a formula that gives radiant energy density as 4 * sigma * T^4 / c. I am trying to figure out how this...

Apr1207 08:39 AM
lpfr

1 
1,833 
How do I explain to my Engineer friends that a ball will actually travel further in humid conditions b/c humid air has...

Sep704 02:26 PM
bobbykilkenny

9 
18,589 
I recently noticed that the density of an electron, assuming it is a particle, was e21 gm cm3. This is e7 x more than...

Jul1110 09:18 AM
Naty1

5 
2,207 
Hi
assume J = I/A = equal in a circular segment of wire
then after a while those electrons forces other...

May1209 11:42 PM
Born2bwire

7 
1,703 
I've spent hours trying to understand conceptually how to find the density of moist, hot air at high temperatures, eg...

Dec2813 06:35 AM
Chestermiller

11 
398 
we know that density of water is maximum at 3.98°C but when it is cooled below 0°C, will its density decrease by...

Mar313 08:27 AM
deep838

1 
663 
Would a big ball weighing 100kg with a diameter of 1 meter float in water?
I guess my question is, no matter how...

Mar112 06:07 PM
Redbelly98

4 
835 
The definition for density
\rho\equiv \frac{m}{V}
is troublesome because it involves this arbitrary Volume. ...

Dec1410 06:30 PM
Nabeshin

4 
1,634 
I'm interested in an equillibrium state between pure liquid (e.g. water)
and its vapour preassure mixed with other...

Nov2410 06:20 PM
GeorgeRaetz

1 
931 
Is there a relation between the deceleration experienced by a body in motion to the density of the medium? Stokes' law...

May1413 11:35 PM
s0ft

10 
752 
I need the dependence of the concentration of salt in water and refractive index of this solution but i dont know it...

Oct2110 11:32 AM
jaykay99

0 
1,085 
My question relates to fiber optics, and probably also general optics.
I have a broadband SLD source, which can be...

Jan2209 12:06 PM
Andy Resnick

6 
917 
how do u account the depression of freezing point an o/w emulsion which has sorbitol to aid tablet formation by freeze...

Mar1709 01:36 PM
goku

0 
1,274 
Dear all,
I have a question concerning Depth of Field –*I'm trying to find a depth of field calculation method that...

Jan612 09:03 AM
Andy Resnick

5 
2,088 
$${\rho}({\lambda}) d{\lambda}=E({\lambda})*f({E(\lambda}))*D({\lambda})d{\lambda}$$
$${\rho}({\lambda}) d{\lambda}$$...

Dec713 05:47 PM
Outrageous

2 
371 
One of the formulas I came across while doing problems with simple parallel plate capacitors was E = V/d, where E is...

May312 03:46 PM
jtbell

3 
10,311 
hello smart people
I came across a weird equation for entropy and do not know how it was derived.
It looks like this...

Sep608 08:39 PM
Count Iblis

3 
5,257 
Hi,
Anyone knows the derivation for Newton´s formula F = ma ?
Any help is importante for me.
Thanks

Sep2111 02:48 AM
harrylin

36 
18,547 
I am looking for a reference (derivation) for this exact formula given for "the magnetic field due to a dipole \mu...

Apr1309 07:32 AM
jtbell

1 
2,862 
Hello everyone, I really run into a problem here.
The magnification equation for mirrors describes such a...

Jun1212 01:11 AM
Simon Bridge

10 
4,115 
I was thinking about Newton's cooling law, which was originally derived empirically, and is often described as an...

Mar2210 08:03 AM
SpectraCat

2 
1,712 
Hi, Im getting started on analytical mechanics but need some help understanding some of the things that is said in my...

Aug3012 01:10 PM
voko

19 
1,086 
Does anyone know of a derivation or has a reference to the derivation of the 2D KdV equation (known as the KP equation...

Jun912 06:35 AM
hunt_mat

4 
1,055 
Hello,
does anyone know how to determine the PSF (point spread function) of an optical system? It would be ok also...

Nov212 02:48 PM
mnb96

0 
478 
Two boxes are side by side on a floor with friction, from the left a Force acts on them. To be more concise about the...

Apr213 10:53 AM
P.Bo

1 
478 
Hey everyone, am new to this forum and i have a few questions some of you will hopefully be able to help me with. I...

Dec1309 12:41 PM
marcusl

1 
1,105 
Hi, I have some questions about the derivation of the Boltzmann distribution, for instance as in Mandl's "statistical...

Aug809 10:49 AM
haushofer

6 
1,370 
Hi:
How do you derive the Boltzmann equation?
Thanks.

Dec610 10:04 PM
quantum123

8 
6,112 
I have been reading about the derivation of Clausius' Inequality and there are a few things I do not understand. I...

Oct1913 04:47 AM
CAF123

0 
423 
Hi,
Got a problem with the following derivation:
Coming from the Helmholtz equation one gets:
...

Sep1712 04:26 AM
OneMoreName

2 
1,182 
I have stuck at a step during derivation.
Here it is.
D=bv
mgbv=ma
a=g\frac{bv}{m}
\frac{dv}{dt}=g\frac{bv}{m}...

Feb1511 09:58 AM
AlephZero

2 
1,675 
Dear All, I need your help with a present problem 
I am a student pilot, and want to see the derivation for the...

Feb1108 08:11 AM
Lojzek

2 
4,233 
So, I'm reading Holm's Geometric Mechanics Part I, and in it he wants to derive the Eikonal equations from Fermat's...

Jan1112 06:36 PM
Matterwave

2 
1,828 