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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,839 
This is an actual reallife problem. There is a machine that winds film at my work. I need to determine the torque...

Aug1207 05:30 PM
wannabe_genius

0 
2,578 
I recently noticed that when a cup of tea was stirred, the floating leaves collect at center of cup rather than outer...

Oct1511 01:12 AM
A.T.

22 
2,578 
Suppose that two photons are the same and propagation in opposite direction in vacuum, the energy of this system of...

Oct107 07:54 PM
Claude Bile

7 
2,577 
We can know about distant stars temperature,its elements etc by observing its spectra... But that star has a velocity...

Oct2512 03:54 PM
Ezio3.1415

10 
2,577 
recenty i read the rocket equation, derivation of, however i think i have a slight confusion with signs
suppost...

Nov2710 01:02 AM
yathiraj

8 
2,576 
F=μmg. How was μ calculated? Obviously experiments were needed. So, done the experiments, what's the exact...

Mar1611 09:47 PM
RandomMystery

37 
2,576 
hi
i am looking for an equation that gives me the potential energy of 2 quadrupole moments and their mutual...

Jun1711 12:10 AM
liuxunchen

4 
2,576 
Hi, I am wondering if anyone here has heard of or can explain this variation of the right hand rule:
Most websites i...

Oct2310 09:11 AM
Cruikshank

2 
2,575 
Does anyone know where I can find Feynman's derivation of the Universal Law of Gravitation?

Sep905 02:01 AM
Andrew Mason

4 
2,574 
My professor brought this up in class the other day, but has yet to elaborate on it and i can't stop thinking about...

Mar2808 01:28 AM
harshant

6 
2,574 
Hi,
Could someone explain the elementray concept and calculations behind a fringing field sensor. As shown:
...

Jul1506 03:24 PM
lalbatros

11 
2,572 
I'm a bit confused with this topic we're supposed to be writing a paper on:
"Thermodynamical Irreversibility VS...

Nov2203 02:36 PM
krab

1 
2,571 
I hope this comes under the classic physics roof. Do any of you play the game and would like to offer your opinions...

Feb1504 08:37 PM
russ_watters

3 
2,571 
Is it possible for the kvector to be a function of space (in the context of EM waves)? What would it imply if this...

Apr2907 06:13 PM
robphy

8 
2,570 
I'm a PhD student (not in physics) working on a research problem where I need to use the Lagrangian/Hamiltonian...

Dec2308 07:44 PM
gumby55555

4 
2,570 
Hello I am a graduate student and it is my first year in physics. Our instructor showed vector product with Levi...

Oct3110 05:54 PM
vishal007win

1 
2,570 
what kind of sources of light generate sinusodially varying electric field that is solutions of the form
...

Nov107 06:50 PM
Claude Bile

7 
2,569 
Assume there is a boat of length 4 m weighing 40 kg. One man of weight 50 kg is at one end (A) and the other of weight...

Jul2911 12:34 PM
Dickfore

31 
2,568 
Hello, I have read over many textbooks and websites (including posts on this forum) relating to the concept of tension...

Mar1207 07:04 PM
p3t3r1

10 
2,567 
Hi, I'm not sure this falls under the homework category, but I posted this here because I think this is more of an...

Aug2209 11:14 AM
jfierro

5 
2,567 
I can't find the THEORETICAL definition of "strain optic coefficient" online. I googled and wiki'd enough. Can someone...

Jan1212 10:29 AM
Studiot

4 
2,567 
Can someone explain this please.
From what I understand momentum is often the more fundamental as it is spatially...

Feb412 12:18 PM
ardie

12 
2,567 
why p type semiconductor is electrically neutral and what is the concept of drift current?

Dec2712 03:24 AM
Studiot

11 
2,567 
Before I get yelled at for crossposting, it was advised that I post this query here, as opposed to the celestial...

Oct304 05:56 PM
pervect

9 
2,566 
Ok guys everyone knows teh solid Pressure = P / S but i have a question..
I though about an object that falls from...

Apr405 07:10 PM
Andrew Mason

4 
2,566 
Hellow, I came upon this problem when working out the power developed in the cylinder of a doubleacting steal engine....

Jun1608 04:15 AM
afternoonslow

0 
2,566 
Epsilon0, the electric constant, and Mu0, the magnetic constant, were introduced in Coulomb's Constant and Ampere's...

Dec2509 08:47 PM
LucasGB

16 
2,566 
Your standard firstpostpleadingforhelp here :)
This doesn't make sense:
Say you've got a setup like in...

Sep1904 07:05 PM
Reisen

2 
2,565 
Hi,
When exactly does the phase change of \pi occur when a EM wave reflects from a surface? I notice that it...

Oct308 01:05 PM
Doc Al

1 
2,565 
I wanted to ask which would provide the largest total BTU cooling regular ice from water or dry ice to reach a...

Mar2609 04:14 PM
mgb_phys

1 
2,564 
I know the mathematical and geometrical reason, but does there exist a physical interpretation behind this?
Thanks...

Nov1111 11:58 AM
2milehi

8 
2,564 
I'm probably going to make a fool of myself for asking this, but that's what the anonymity of the internet is for...

Jun2012 07:06 AM
mischeya

4 
2,563 
I bumped into this physicis problem about 2 weeks ago and it is much harder than you might think:
A ball is dropped...

Jan1906 02:07 PM
Galileo

1 
2,562 
Suppose we have box with a volume V which is divided down its middle.
So the box is split in two sides with equal...

Dec607 03:08 AM
LTP

8 
2,562 
I was thinking the other day about how conservation of momentum works in terms of a closed system consisting of a...

May1309 08:08 PM
worldrimroamr

7 
2,559 
Hello everyone
I came across a few (relatively standard) problem in elementary classical mechanics...
A mass A...

Jan2005 05:03 AM
maverick280857

3 
2,558 
I am having trouble understanding this. For example, say I have this:
I know the...

Aug2610 09:07 AM
nasu

1 
2,558 
hi,
in the case of elastic collision of two balls in constant speeds, if we took the origin in the center of of one...

Feb1006 06:51 PM
Doc Al

9 
2,557 
I just thought of something, imagine this scenario:
You have an empty bottle of sode\water(whatever) and you hold...

Feb907 03:52 PM
disregardthat

11 
2,557 
I have a small steel cylinder centered inside a larger steel cylinder. The remaining space is filled with 60% silica...

Jun2410 06:22 PM
Bacat

0 
2,557 