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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,892 
How can Ohm's law explain the fact that the resistance of a wire depends directly on length and inversely with area?

Sep1511 01:17 PM
berkeman

3 
1,278 
In Gamow's short book 'Gravity' he describes the effect of lunar gravity on the earth, in particular the seeming...

Sep1511 06:39 AM
A.T.

86 
9,146 
Hello everybody,
i previously posted a topic about an exercise on luminance that was (appropriately, I admit) moved...

Sep1511 12:42 AM
Ken G

3 
1,699 
Howdy,
I am looking to find the rate of ascent for a weather balloon filled with helium. My assumptions as of now are...

Sep1511 12:06 AM
thespaceman

2 
1,859 
I am having trouble conceptualizing and drawing situations that involve glass, or any other medium that light travels...

Sep1411 10:23 PM
JeffKoch

6 
1,044 
There is patent which describes new type of something similar to capacitor based on
quantum effects....

Sep1411 07:19 PM
Drakkith

1 
1,277 
Simple question, if the force of gravity is proportional to mass and distance, as in Newton's and Einstein's theories...

Sep1411 10:08 AM
ZapperZ

10 
2,710 
What happens to gas temperature in different parts of closed chamber (let's say for arguments sake, a closed cylinder...

Sep1411 09:21 AM
sweet springs

9 
1,652 
Hi guys,
I have this problem, I would like to use microwave to heat gold nanoparticles (~5nm) dispersed in water....

Sep1411 08:36 AM
PavelDV

0 
1,073 
why does a body has inertia and from where does it get that inertia,theoretical explanation will suffice?

Sep1411 08:33 AM
nouveau_riche

10 
1,197 
Hello everyone, first time poster.
A fairly basic question: What is the mechanism by which synchrotrons produce...

Sep1411 05:29 AM
Billy70

3 
1,165 
So I built a little homemade CD/cardboard box spectrometer just for fun, but a weird thing happens with it. I keep...

Sep1411 12:49 AM
HyperSniper

0 
609 
Is it possible to find the distance covered in a certain time when acceleration depends on velocity, such as an...

Sep1311 11:00 PM
Khashishi

2 
1,531 
When I shine two different lights at a single spot on a white screen, say, yellow and blue, they both hit the spot and...

Sep1311 06:34 PM
sweet springs

9 
1,693 
suppose that i have a piece of magnet close to a piece of diamagnetic material
the piece of diamagnetic material is...

Sep1311 02:25 PM
carmatic

2 
1,116 
The phase space trajectories of an autonomous system of equations don't intersect.
Can this be proved...

Sep1311 02:00 PM
olivermsun

1 
1,744 
Hey!
I stumbled across this problem while reading Wald's "General Relativity", but it belongs to Electrodynamics....

Sep1311 01:14 PM
Lurian

0 
1,338 
for the adiabatic expansion of a gas,
why is the temperature drop smaller for a real gas , vs a bigger drop for an...

Sep1311 01:02 PM
Philip Wood

13 
4,105 
Hello,
I know this seems silly to ask, but how could I figure out how much heat was given off when I know the force...

Sep1311 12:50 PM
Doc Al

5 
1,134 
I've been reading up on photolithography trying to understand how processors with subwavelength features can be made...

Sep1311 11:18 AM
chrisbaird

3 
1,109 
I'm having some difficulty applying Gauss's Law to metal plates. From what I've studied it seems to me that Gauss's...

Sep1311 06:54 AM
BruceW

7 
2,534 
I have spent lot of time trying to understand scattering from Goldstein but in vain. The general equation of an orbit...

Sep1311 06:39 AM
Amith2006

0 
936 
I need to adjust the safety trip at 110% of the nominal load ( 130 tons ).
This means that I need to load the...

Sep1311 04:43 AM
Marinel

10 
2,366 
So, am I understanding this correctly? The movement of electrons is the fundamental interaction of all that we...

Sep1311 03:16 AM
Drakkith

3 
939 
I know what they are Mathematically and their definitions but looking at them from an intuitive way as a property of...

Sep1211 08:58 PM
Ken G

13 
3,610 
Good afternoon,
I've tried to find a simplified model for the dynamic forces acting on a rolling wheel, but have...

Sep1211 08:20 PM
Spinnor

3 
1,676 
For an ideal gas, PVK=C, where C is some constant and K is the ratio of the specific heats. K is obviously the same in...

Sep1211 04:40 PM
Philip Wood

3 
2,836 
weight is more at night than day. is this right? if not why?

Sep1211 01:17 PM
D H

15 
1,695 
Hi all,
I am seeking for an optical design an simulation platform. There will be splitters, combiners and mirrors...

Sep1211 11:56 AM
y33t

2 
1,032 
A spinning top has angular momentum that creates a force that keeps it from falling over, and it precesses. Mass in...

Sep1211 11:12 AM
chrisbaird

4 
1,699 
Electric potential is the work done in moving a unit charge from infinity to a point in an electric field.
Electric...

Sep1211 10:04 AM
Bhargava2011

10 
3,896 
Is this following correct? :
When you push a crate along the floor at a constant velocity for a long time, you get...

Sep1211 09:52 AM
Bhargava2011

2 
1,059 
Hi guys,
I'm stuck on some thermodynamic calculations and I would really appreciate some help!
I'm trying to...

Sep1211 08:01 AM
bobboviking

0 
2,419 
if a gas expands isothermally but irreversibly from V=1litres to V=2litres under constant external 1atm pressure,
...

Sep1211 05:07 AM
quietrain

26 
3,941 
Say I launch an object (a cart) up a frictionless inclined plane at an angle of 'theta' to the horizontal.
...

Sep1211 01:25 AM
Ken G

3 
4,696 
Many runners twist in their upper body while they run. You can see this by watching the logo on their teeshirt move...

Sep1111 09:25 PM
Ken G

1 
1,333 
Hi,
If I have a magnetic field orientated in the xdirection, a dipole positioned on the zaxis how do I find which...

Sep1111 08:42 PM
Spinnor

1 
1,310 
So every mountain biker or motocross rider knows to never grab the front brake in the air. When you do the front end...

Sep1111 06:24 PM
berkeman

11 
1,780 
What are some currently unresolved problem in thermodynamics? Thanks

Sep1111 05:06 PM
Andy Resnick

3 
2,493 
Hi all. I was working on a circuit question with inductors and I then had a question. Lets say we have a simple...

Sep1111 01:30 PM
perplexabot

3 
1,270 