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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,982 
Sorry if this question has already been considered in this Forum (I'm sure it is but I can't find it now).
A rigid...

May2214 07:01 AM
Doc Al

31 
740 
What are cyclic devices exactly? Are heat pumps and refrigerators both examples of cyclic devices? Also is a heat...

May2114 05:35 PM
dauto

3 
224 
My book states:
''An engine is a device that turns heat energy into work''
I know the definitions of both heat...

May2114 04:55 PM
dauto

3 
228 
Could anyone please write the derivation (or forward me to the source of derivation) of the formula related these two...

May2014 06:49 PM
UltrafastPED

3 
246 
Hey guy, this is one of the question in my uni work (I'm not sure whether my answer is correct or not, please have a...

May2014 06:20 PM
paisiello2

5 
321 
I have a short question which I have been discussing with a fellow student and a professor. The question (which is not...

May2014 05:20 AM
muscaria

2 
233 
Hello, as you might have guessed, my question revolves around thin film optics. My intention is: Given a two thinfilm...

May1914 10:13 PM
Simon Bridge

9 
309 
Hello!
I am not quite sure how do i verify the complex wave function of EM wave
\vec{E}(x,y,z,t)=...

May1914 06:09 PM
melodyyyylwy

2 
216 
I was doing a question in Taylor book (example 3.3) where a sticky putty is thrown at a stationary wheel. To solve it...

May1914 04:01 PM
D H

3 
225 
Hi everyone,
I am trying to calculate the decrease in magnetic field strength over distance, using a formula I...

May1914 03:46 PM
Meir Achuz

4 
338 
okay so I suck at LaTex so i'm not going to put the actual equation, but it's not important for my question.
In...

May1914 01:29 PM
WannabeNewton

1 
232 
I'm currently reading about thermodynamics and osmosis and I happened to stumble across this paper. There is one thing...

May1914 11:23 AM
nossren

7 
324 
I read this
They do not talk about the metal between glass and air! Reflection occurs between glass (low index)...

May1914 10:54 AM
naima

2 
301 
I'm confused why when using cylindrical coordinates three unit vectors are needed. My book says that the three unit...

May1814 08:19 PM
Matterwave

1 
219 
There are two sphere of radius a and b and they are connected by conducting wire. Then why the electric potential...

May1814 01:48 PM
berkeman

7 
232 
This confusion is about the following problem:
Suppose the entire region below the plane z=0 is filled with uniform...

May1814 09:59 AM
Meir Achuz

5 
283 
Hi, please could someone explain why the magnetic field is stronger at the poles of a magnet. I know that the field...

May1714 08:50 PM
enorbet

3 
332 
http://www.ilrn.com/ilrn/books/spcp07h/Fig_20_14a.jpg
I understand how motional EMF is produced, the magnetic force...

May1714 01:07 PM
BruceW

11 
335 
Hi I'm confused after reading the definitions of physical Quantity and physical property:
Definition from...

May1714 11:00 AM
dauto

3 
373 
Hi, I've read that the speed of em waves in the vacuum is the electric field component frac the magnetic field...

May1714 10:25 AM
mfb

1 
212 
Hello all,
I would like to know a method to trap light. That is, it should be pretty simple and nonelectric. It...

May1714 02:15 AM
albertrichardf

12 
290 
I am trying to make a very strong magnet that will only last for a short pulse, just a fraction of a second, with a...

May1614 10:50 PM
Pharrahnox

2 
210 
When a body is held or rests in equilibrium in contact with a surface (e.g. a slope, the edge of a block etc.) how do...

May1614 05:14 PM
jbriggs444

7 
237 
I am trying to find an equation that tells the strength of a magnetic field a given distance away from the source. It...

May1614 03:04 PM
mfb

22 
21,480 
Hey guys, umm i'm just gonna get straight to the point, why is the notation of dy/dx for example is being abused so...

May1614 10:22 AM
D H

22 
530 
Hi All,
I am thinking about building a simple electrical generator, and I am trying to make sure I clearly...

May1614 05:30 AM
Pharrahnox

7 
456 
When water is vigorously shaken the kinetic energy and, hence, the motion of the molecules increase. Which particular...

May1614 03:05 AM
Simon Bridge

1 
208 
To prepare for a future physics course, I googled Newton’s Laws and then found about the Work Energy Theorem. I can...

May1514 07:30 PM
russ_watters

56 
1,158 
Hello everyone,
I was wondering, is there any way of calculating the time it takes for two objects in thermal...

May1514 07:10 PM
Chestermiller

1 
237 
Hey guys, I've been wracking my brain for a while, and thus I have landed here yet again.
My problem is the...

May1514 12:11 PM
crador

3 
378 
If I have a grounded conducting material, then I know that $\phi=0$ inside this material, no matter what the electric...

May1514 05:42 AM
Simon Bridge

3 
204 
I had a bottle half full of ice and filled it with water and placed it in my fridge. I noticed that the ice was taking...

May1514 04:18 AM
DrClaude

1 
244 
In the semiclassical treatment of the ideal gas, we write the partition function for the system as $$Z =...

May1514 01:38 AM
WannabeNewton

1 
242 
I'm working on research into the feasibility of separating out the infrared rays above 1200 nm in sunlight for solar...

May1414 10:10 PM
SIM77

6 
213 
A new variational principle is presented in this paper: http://arxiv.org/ftp/arxiv/papers/1112/1112.2286.pdf
When...

May1414 02:47 PM
rrhd

1 
182 
To every scalar field s(x,y) there corresponds a 'constant' vector field x = A s(x,y) and y = B s(x,y), where A,B are...

May1414 01:16 PM
UltrafastPED

6 
200 
First, I'm a second year high school physics student so my thinking may be halfbaked. I was wondering what motion a...

May1414 12:24 PM
Agrasin

2 
207 
In a beam of unpolarised light, there are thousands of light waves of all polarisations. At a given point along the...

May1414 11:00 AM
maline

6 
388 
Hello Everybody,
Span efficiency factor appears in the liftingline theory of Prandtl describing Lift and vortex...

May1414 04:07 AM
A.T.

22 
1,912 
I have a question that has puzzled me during the last couple of days. Suppose that there is a system (e.g. a small box...

May1414 01:16 AM
Jano L.

14 
526 