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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,882 
What is the exact effect that metal has on rf (any electromagnetic waveform)? Is it attenuation, reflection,...

May2013 10:19 AM
jastewart

9 
530 
I'm taking a first year physics course and have been having a little trouble with the basics of newtons laws and...

May2213 01:35 AM
raopeng

6 
725 
In circuits, we have no problem saying that the voltage difference between two point is \cos(\omega t), but what does...

May2113 08:20 AM
stevenb

8 
1,349 
I have a few questions pertaining to some concepts in electrostatics, I'd be grateful if someone would help me out.
...

May2213 01:27 PM
phymathlover

9 
1,089 
Which has the least entropy?
A 1kg diamond vs 1kg living organism
I've gather that living things are generally...

May2013 06:13 AM
bcrelling

11 
905 
Hello all,
I am working on a science project based upon paper, and I have chosen the affect of friction between two...

May2113 11:38 AM
Atham

15 
1,034 
Hi fellow members!!!
I would like to ask a silly question because my basic concepts are quit weak. Since according to...

May2213 06:29 AM
adjacent

8 
1,267 
Yesterday I got fascinated by the camera recordings on the Atlantis Space Shuttle....

May2113 03:24 PM
LastOneStanding

10 
850 
what is the mechanism by which light changes its speed and wavelength while travelling from one medium to other. I...

May2013 01:43 AM
shantanuphadke

2 
353 
Hello Dear Fellows!
We all know that light is an electromagnetic wave and also we know that...

May2013 01:41 PM
nsaspook

8 
705 
I am having few doubts while studying electric field which i am putting here
Suppose there is a spherical metallic...

May2013 10:16 AM
Simon Bridge

15 
938 
Hi !
I've been working about assignments problems and how to solve them. I will have to do a presentation about it...

May2013 06:43 AM
Simon Bridge

4 
590 
I have been looking at mass spectrometers, in particular the interactions between the Bf ind of a charged particle in...

May2113 09:03 PM
mesa

8 
668 
http://youtu.be/FZiBezCMUck
Can anyone help to explain what is going on here?
What are all the variables that might...

May2013 07:02 AM
ROBwithaB

0 
401 
When I look at a distant light source (like car headlights, or street lamp lights) I notice colors of the visible...

May2013 03:17 AM
filipg

2 
386 
Let's say I have a circuit consisting only of a finite number of batteries and resistors, all ideal. Given an...

May2213 07:41 AM
stevenb

10 
863 
Hello
Can anyone tell me how the absorption of a polystyrene nanoparticles scales as a function of its diameter.
...

May2013 12:06 PM
Excom

2 
395 
there are two points A and C having a finite potential difference.they are connected by a wire of non zero...

May2013 07:34 AM
projjal

3 
703 
In my physics book there is an example of making a square wave by "simply" summing up a few cosine waves. The book...

May2013 03:58 PM
MisterX

5 
845 
During electrostatic induction,a posivitiely charged body is brought near to a uncharged body.During this uncharged...

May2013 07:57 AM
projjal

2 
401 
I have been looking for a better way to power my electromagnet than a bunch of AA batteries, and am now thinking of...

May2213 02:22 AM
CWatters

3 
631 
Hello,
I was wondering if there is a conceptual explanation for when current leads voltage or vice versa for...

May2213 04:43 PM
mikeph

3 
587 
Given some chemical reaction, A+B > C+D (all are ideal gases) that occures in 298K and 1 atm.
why can't I...

May2113 12:07 PM
lightarrow

6 
560 
I am doing a paper on the physics in Valve's Portal and got interested in the "Long Fall Boots" that prevent any...

May2213 01:58 AM
CWatters

2 
1,127 
Virtual work principle states: δW = \sum^{N}_{i=1}\vec{F}_{i}\centerdot δ\vec{r}_{i}
And from this, we can see...

May2113 02:46 AM
Astrum

2 
523 
I'm kind of rushing through first year physics cause im doing it self paced, but I am realizing now that as an...

May2013 06:43 PM
Jorriss

2 
345 
I have a question about solenoids.
The formula for the magnetic field energy density is:
...

May2213 10:08 AM
milesyoung

6 
843 
i) If a wall breaks when it gets hit by a cannonball, did the wall exert an equal and opposite force on the...

May2113 04:58 PM
faldahlawi

3 
597 
I've been mulling this over all weekend, and I've decided to get some help on this. The problem is writing a function...

May2013 07:25 PM
milesyoung

4 
620 
I'm modeling a single 3D rigid body in preparation for some more complicated modeling in order to gain a better...

May2213 06:56 AM
D H

5 
1,365 
Hello,
I am wondering, what is the physical interpretation of the angular frequency of AC voltage? I don't see the...

May2013 08:40 PM
BruceW

1 
734 
Any experts on Griffith's fracture theory?
I am studying the subject and I am having hard time finding out if the...

May2113 01:19 AM
wonderer_85

0 
402 
How is it that bubbles form on the bottom of a surface of a pot of boiling water?
I think that there is probably...

May2113 10:26 PM
klawlor419

9 
1,419 
Hi.
I'm having some difficult in understanding something about the dipole term in a multipole expansion. Griffiths...

May2113 08:09 PM
LastOneStanding

1 
504 
I wanted to mention that this solenoid has many winds over many layers. The thickness of the windings is 2.4 inches...

May2213 08:10 PM
eigenstaytes

0 
472 
Can we convert energy to matter?

May2113 08:49 PM
velocity boy

12 
1,330 
I'm having some difficulty understanding exactly what the difference between the definitions of these values are. As I...

May2213 05:25 AM
Suvat99

0 
576 
Hello everyone,
A friend of mine came up with this question in class and I really do not have a good answer.
...

May2213 05:15 PM
Zag

4 
1,074 
A rough sketch of experiment.
http://i43.tinypic.com/14t4sk5.png
the red dots represent a side view of path...

May2213 04:45 PM
tinytim

3 
548 
what are the differences? Every example I find usually has a derivative or integral or some kind of calculus defined...

May2213 06:44 PM
HomogenousCow

4 
774 