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Apr2211 05:27 AM
ZapperZ

2 
70,634 
The aim of this thread is to highlight recent (as in within the past 3 months) noteworthy physics papers that have...

May614 04:32 AM
Cthugha

168 
190,856 
Hi,
I've got a question about fitting a known function to a measured data.
Suppose I want to find X parameters...

Nov2111 07:37 PM
gsal

1 
942 
http://members.aol.com/crebigsol/awards.htm
this may be old but did anyone win?

Aug1903 11:33 PM
Brad_Ad23

4 
2,635 
Hello my university is giving out little "mini" grants for undergrad research and I was wanting to get involved...

Oct2110 09:26 AM
Davide86

3 
1,227 
Hey guys, what's the difference between percent deviation and percent error?? I'm totally confused... how do I compare...

Sep2011 04:27 PM
nmah

4 
20,007 
Hi if i have to find the percentage error of a volume measurement in a cylindrical column , how do i do it please?
...

Oct211 12:08 PM
Irishwolf

0 
713 
I am starting a new thread on this subject because I feel that the subject under discussion is of the greatest...

Aug1704 11:40 PM
McQueen

33 
3,243 
From Wikipedia: "Positron emission or beta plus decay (β+ decay) is a type of beta decay in which a proton is...

Jun2811 11:55 AM
treehouse

4 
2,300 
Hi. I am working through Schutz's Geometrical Methods of Mathematical
Physics. In the section on Hamiltonian...

Jul1407 05:00 AM
AGS

0 
1,446 
I was checking the NIST site with their Hydrocarbon line database
search utility, and the frequencies of the lines...

Jun2909 04:10 AM
textbooks

0 
1,025 
Im currently researching momentum, kinetic energy and potential energy. I came across the idea
that potential energy...

Aug1014 09:33 AM
mfb

6 
352 
I'm curious, which vector notation is preferred by physicists/engineers/mathematicians? In linear algebra we used...

Feb111 08:44 PM
Rap

3 
2,109 
What is the likelihood of anything gaining enough momentum that no other outside forces could ever slow it down any...

Mar1910 09:58 AM
Redbelly98

3 
1,010 
Hi,
I'm trying to use a polariser/pockels cell/analyser combination to make a fast optical switch. I have build a...

Dec108 05:58 PM
GlenS

0 
1,449 
I came across this article today....

Jun1809 01:08 PM
jamesbuk

10 
1,476 
So I was reading through a textbook and came across the term 'close encounter' but no definition or explination of...

Jun1110 06:02 PM
DaveC426913

5 
1,193 
Hi, I'm trying to create a 'curtain shooter' game. Essentially this is a side scrolling shooter (think Gradius,...

Dec305 02:34 PM
Bucky

2 
2,612 
Could someone write a formal definition for "number degrees of liberty of a system". Thank you very much.

Feb1005 09:17 PM
dextercioby

7 
2,912 
When a car is approaching it has a higher frequency and shorter wavelength. When it has passed sound waves are a lower...

May612 04:33 AM
Rorkster2

16 
2,328 
I read the following article with interest:
http://arxiv.org/ftp/arxiv/papers/0810/0810.0592.pdf
What is not...

Oct908 07:38 AM
Andy Resnick

1 
979 
Why do people always use the misleading term 'escape velocity'?
If I had a rocket whose engines provided a thrust...

Aug605 05:57 AM
ZapperZ

15 
2,405 
why call 'flat' field spectrograph ? what does the meaning of 'flat'. another question: if I what to focus the ray...

Sep3013 08:54 AM
Andy Resnick

3 
690 
What is 'High' Temperature superconductivity?

Oct3005 07:56 PM
shyboy

5 
1,311 
We know If two or more resistances connected in series with an applied voltage 'V', then the equivalent resistance of...

Aug2110 02:30 PM
AJ Bentley

1 
836 
Hello again.
I come with another physics concept I am struggling with. At first I thought I understood this but the...

Jun1308 08:58 PM
uby

3 
2,158 
Hi all,
is it true that in any spacetime M (aka real smooth 4dim connected
Hausdorff paracompact manifold without...

Mar1007 05:00 AM
Marc Nardmann

1 
1,363 
Can anyone explain to me just how we can 'look' at an atom and its, um, components? And how the process of 'looking'...

Jul103 02:34 PM
arcnets

23 
3,775 
Hi, i am building a basic particle engine and i need to know what affects a 'particle' (a bit of dust for instance), i...

Dec1804 08:22 AM
Tree Penguin

11 
1,391 
I'm not exactly a physicist, but I do understand most things.
I'm looking for a formula that will give how far into...

Jul704 08:41 AM
Nereid

17 
3,477 
how can wec trace the origin of push and pull to electromagnetic forces? I mean when we push a thing what actually are...

Jun2807 05:21 AM
HallsofIvy

2 
6,028 
I recently came across the paper 'Relation between the psychological and thermodynamic arrows of time' (arXiv).
...

May814 07:43 PM
dauto

1 
344 
By rolled, I mean this kind of basic homemade capacitors:...

Oct112 10:43 AM
sophiecentaur

22 
1,885 
Hello;
I was reading a book that described Werner Heisenberg's thought experiment. It said that, when a particle...

Oct1410 05:24 PM
tinytim

1 
1,597 
Hello,
I have a real world sports question I need help with:
I am looking for an accurate formula to calculate...

Jan2512 08:56 AM
Studiot

1 
1,419 
Q1)Electron has both mass and electrical field, can we said that electron itself possesses both mass and electrical...

Apr606 10:39 PM
AlienUFO

0 
1,523 
OK, this is just a little musing I had and I wonder what anyone who has real physics knowledge thinks about it :smile:...

Jan2404 11:37 AM
hazhar

0 
1,583 
When bass plays from a subwoofer, a tree falls, a bomb explodes or something similar there's a very real physical...

Mar2212 11:21 AM
Ryan_m_b

6 
1,486 
Has anyone heard any details about this?...

Nov3007 12:19 PM
ZapperZ

2 
1,338 
From observation, whenever I want to 'zoom in' in a camera, the lens expands outward. What is the reason behind this?...

Dec2706 02:51 AM
pivoxa15

17 
2,725 
Hi all, what do you think about this:
http://www.plusminustheory.org/pmt_home.htm

Aug3103 03:43 PM
arcnets

0 
944 
hello,
I can't seem to make sense out of amper/meter....one amp flowing throw a wire with a length of 0.5m would be...

Aug812 02:50 PM
tinytim

7 
1,182 