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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,714 
So i've been studying optics on my own for about 2 months now and I am having a lot of trouble understanding what...

May1811 07:13 PM
Ertosthnes

8 
23,098 
I'm seeking some clarification on a topic found in Jackson 'Classical Electrodynamics' Chapter 5. This deals with the...

Mar2211 05:38 AM
netheril96

8 
17,126 
This is a question about the text of Hailiday/Resnick/Walker 8th ed. p217  219. It's not a homework problem, but...

Apr2511 01:23 PM
Doc Al

8 
6,797 
What?
W = \frac{\epsilon_{0}}{2} \int E^2 d \tau = \frac{\epsilon_{0}}{2 \left( 4 \pi \epsilon_{0} \right)^{2}}...

Feb411 03:02 PM
kcdodd

8 
1,890 
What's the most persuasive argument for using the potential phi and A as independent deegres of freedom in the...

Feb511 11:05 AM
Dickfore

8 
1,647 
I am hoping to find how to determine the heat available from focused and concentrated sunlight. I am not confident in...

Feb2011 06:57 AM
ThoughtRay

8 
1,885 
sorry if the title is not clear, if you have a better idea i'll change it.
say i drop a 10kg book to the floor....

Feb811 08:48 PM
AlephZero

8 
974 
If the law of conservation of mass states, in a closed system mass is never lost, how is it, when matter is...

Feb1611 01:20 PM
berkeman

8 
1,412 
why are good conductors of heat good conductors of electricity as well?

Feb2411 08:17 AM
aakash123456

8 
1,334 
in the case of a spherical conductor the charges reside on the surface...the electric field is perpendicular to this...

Feb2411 01:44 PM
abhiroop_k

8 
2,686 
I have problem understanding why the surface integral disappear when taking the volume to very large in this equation:...

Mar111 03:31 AM
yungman

8 
1,564 
What i mean to say is that, i understand the concept of "change of distance", "change of time" and other changes and...

Mar711 08:53 PM
ijkijk

8 
2,321 
Hi there, physics lovers. I'm studying field theory. So far, so well. I got it with the lagrangian density. I...

Mar911 07:30 AM
MManuel Abad

8 
1,465 
See the figure
http://www.physicsforums.com/attachment.php?attachmentid=32890&stc=1&d=1299618716
The block A...

Mar911 11:53 AM
Subductionzon

8 
3,651 
Why is it that simple balances always come to rest in a horizontal position when equal weights are placed on both...

Mar1711 03:14 PM
RedX

8 
1,625 
For example, you have an electrical circuit, which consists of a battery of 6V, a zero ohm resistor and a light bulb...

Mar2511 06:42 PM
BackEMF

8 
1,251 
Would anyone be able to explain how to calculate and use bending moments? I have been studying cantilevers and Euler's...

Mar2711 10:21 AM
Studiot

8 
2,999 
So I got this question on a physics quiz:
"You have have two masses, M1 and M2, weighing 1.00 kg and 2.00 kg...

Mar2711 08:11 PM
AlephZero

8 
1,164 
I believe that it is the case that if I were on Pluto, say the sun would appear much smaller, the area of the disc I'd...

Mar3011 11:20 AM
klimatos

8 
2,200 
in the movie i was watching that is set in space, some of the characters get frozen while exposed to the vacuum of...

Mar3011 09:52 PM
DaleSpam

8 
2,919 
Hi there,
If a proton passes through a loop of wire, it induces a tiny current in the wire. Will the proton lose...

Apr611 01:18 AM
willem2

8 
1,369 
I was looking at a situation where a fridge in the back of a truck is just about to tip back due to the truck's...

Apr1111 12:15 PM
DocZaius

8 
1,323 
can a body moving in a straight line be in rotational motion as well?

Apr1411 03:30 PM
QAZI

8 
2,013 
When we are considering the how much optical power a component/pin detector can withstand, are we more concerned about...

Apr1511 05:39 PM
Dr Lotso'watts

8 
3,757 
Dear list,
Imagine a table of upper surface area S sitting in an open field, with nothing on it. We know that S is...

Apr2211 12:44 PM
russ_watters

8 
1,633 
Suppose I put an (uncharged) hollow conducting sphere with inner radius a and outer radius b in an external electric...

Apr2111 08:05 AM
TobyC

8 
2,642 
Can matrix representations of any higher order Clifford Alebras be found ?

Apr2611 09:14 PM
sjhanjee

8 
1,214 
if i have a current carrying straight long wire, I = I0sin(wt)
why is gauss law ∇.E = 0?
i thought only for...

Apr2111 11:35 AM
quietrain

8 
1,427 
What is it that exactly causes an attraction between two masses?

Apr2411 06:23 PM
jtbell

8 
1,081 
Hi everyone,
I'm working on a presentation for a physics class, and I've run into some difficulty. Our group is...

Apr2411 11:49 PM
michaelp7

8 
1,613 
This is highly theoertical and I came up with it taking a standerized test. So with out further adoo,
What would...

Apr2711 07:55 PM
Rage Crank

8 
1,399 
Hi guys,
I know the 2nd moment of area about the z axis is defined as the integral of y^2dA, where y is the...

Apr3011 07:45 PM
ideasrule

8 
2,703 
Hello,
Can anybody explain to me how does this:
dQ=X*dS*grad(T)*dt
t being time and T being TD temperature....

May411 09:24 AM
Bassalisk

8 
2,018 
If you place a charge +q at the exact center of a conducting sphere, will it stay there or move to the surface?

May1311 03:11 PM
Idoubt

8 
1,559 
i need to know how many degrees do i need to be able to find the kinetic energy of the molecule ?? and may i have a...

May1711 06:32 AM
elabed haidar

8 
5,118 
Setting gravitational potential energy's zero at infinity distance, is it safe to say that the limit as r approaches...

May1711 07:37 PM
ZealScience

8 
1,555 
centrifugal pumps and blowers work on the same principal then why centrifugal pumps are needed to be primed but...

May1811 05:36 AM
sophiecentaur

8 
1,295 
So I was thinking about the conservation of momentum. If you throw a handball at a wall, the wall will provide an...

May1811 05:41 AM
sophiecentaur

8 
4,122 
I am pretty much curious to know what actually an electron is? How it is? What is CHARGE? Why there are two types of...

May2311 02:43 PM
DaleSpam

8 
1,736 
Q) A closed chamber containing working refrigerator is pefectly insulated and d door of refrigerator is opened, wat ll...

May2311 02:15 PM
S_Happens

8 
1,584 