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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,870 
Can someone send me some interesting chain problems?

Oct2009 03:39 AM
debanik1

0 
593 
Does the magnetic field around a magnet increase when the distance away from the magnet increases? While using a...

Oct2009 02:07 AM
Gauss20000

3 
2,279 
Hi,
This must be a text book question but I couldn't find exact definitions(quantitative) of these measurements...

Oct1909 11:20 PM
Born2bwire

3 
5,848 
Is the Change in Rotational Kinetic Energy Frame Invariant?
...

Oct1909 10:29 PM
DaleSpam

6 
2,562 
Yesterday I finally, and sadly, put my Matilda 'Southwind' to bed for the winter.
I want to lift her off her...

Oct1909 10:13 PM
Bob S

3 
828 
Is it possible to have magnetic flux through an open surface ?
i mean if there is a circular arc and magnetic field...

Oct1909 02:19 PM
rplatter

1 
690 
I'm only midway to finish my introduction to electromagnetism (level around ResnickHalliday) so I understand the...

Oct1909 01:07 PM
Bob_for_short

5 
890 
I remember reading a thread here on PF about how paper towels can absorb water. I think the answer was that the towel...

Oct1909 08:41 AM
Andy Resnick

3 
786 
It is well known, that a point charge q\delta^3(\boldsymbol{x}\boldsymbol{x}') creates the same electric field...

Oct1909 08:24 AM
Bob_for_short

6 
571 
I have a sphere (mass m, radius r) whose centre of mass is r/2 distance away from its geometric centre. If it is kept...

Oct1909 01:14 AM
raghavgupta93

0 
2,576 
F=ma
How do we define m and F? If their definition both come from this equation, then the equation doesn't really...

Oct1909 12:29 AM
Martin

31 
10,464 
I've been reading about the physics of sound. Perhaps I'm just reading an overly simplified version of the truth, but...

Oct1809 08:54 PM
amannikus26

12 
9,330 
I am doing physics homework and I came upon a problem that I had forgotten how to do, and i do not believe my answer...

Oct1809 12:24 PM
yyttr2

2 
1,769 
In applying F=qvB, must the charge move with velocity V? Or the V is only relative velocity so that even the charge is...

Oct1809 11:01 AM
Bob_for_short

5 
1,181 
Why electrical resistance can make the current in circuit be constant? When circuit is closed, electric field is built...

Oct1809 10:36 AM
f95toli

2 
907 
Good evening,
The definition of jerk is change in acceleration with respect to time. So, we can define it as a...

Oct1809 06:23 AM
pc2brazil

9 
3,979 
Hi, I would like to ask a question about Mutual Inductance and Transformer.
Suppose I have two coils N1 and N2,...

Oct1709 09:50 PM
Bob S

11 
4,447 
it may bit a fuzzy problem but still i have this confusion i.e suppose i have two sphere of same radius & all physical...

Oct1709 07:32 PM
Vanadium 50

7 
965 
Good evening,
(NOTE: This post got a little long; I hope someone has enough patience to read it.)
I selfteach...

Oct1709 12:35 PM
pc2brazil

4 
1,014 
This concerns a debate I'm having with two friends of mine, hope someone here can help.
You have a train travelling...

Oct1709 12:23 PM
Danger

14 
1,370 
I'm a bit confused about the speed of objects rolling down slopes.
In my textbook, it says
"Neither the mass nor...

Oct1709 11:34 AM
Gerenuk

3 
8,930 
The title says it all. I've heard my professor saying that they are not conservative. I'm very surprised by this. ...

Oct1709 09:28 AM
fluidistic

2 
1,138 
Ok, so I've a couple of assignments that require the understanding of the basic principles of buoyancy and...

Oct1709 09:15 AM
Doc Al

3 
2,572 
So I am playing around with the differential form of Gauss's Law:
\nabla \cdot \vec{E} = \frac{\rho}{\epsilon_0}
...

Oct1709 08:38 AM
hbweb500

2 
1,028 
If we consider the following Lagrangian:
L = m * (dot x)^2 / 2  e A dot x  e phi
with A the vectorpotential and...

Oct1709 07:13 AM
Bob_for_short

7 
900 
I want to know what do we use an isolating (1:1) transformer for.
My book says it is to "protect against electric...

Oct1709 02:14 AM
Danger

3 
9,473 
There is a space station of the length L and uniformly distributed mass M on the low Earth orbit. One side of it...

Oct1609 10:37 PM
mgb_phys

1 
598 
I may have made a mistake in calculating, but I just finished lab homework where my calculated momentum was different...

Oct1609 04:13 PM
mathman

1 
589 
I know that accelerated charges give off electromagnetic radiation, but does an accelerated (spinning) magnet give off...

Oct1609 12:27 PM
Bob S

2 
1,249 
Hey Folks
I have rather a silly doubt i guess...
It goes like this
Consider a disc rotating about a fixed axis...

Oct1609 12:05 PM
Franco_v

4 
4,562 
i need a textbook which contains a good discribtion of the nonuniform plane waves .
thanks .

Oct1609 10:15 AM
electric

0 
595 
I think this scenario violates the law of conservation of energy: A ball is rolling twards a fan, witch provides a...

Oct1509 08:40 PM
Andy Resnick

9 
1,934 
Hi!
I'm working on a problem regarding a jet engine and I actually did solve it but I'm not sure about two things:...

Oct1509 06:56 PM
trelek2

0 
747 
...the angular speed of the earth would be increased around ten times?.
I mean if w, that now is 7,27 * 105 rad/s...

Oct1509 04:57 PM
Cleonis

4 
1,655 
how we can explain the differential of lagrangian is a perfect ?L dt

Oct1509 10:46 AM
Bob_for_short

3 
786 
if the lagrangian is time homogenous ,the hamiltonian is a constant of the motion .
Is this statment correct ?

Oct1509 08:57 AM
eman2009

5 
681 
Hi.
The chapter is electric potentials.
In dielectrics, when solving for Q(bound), Q(free) is required.
What...

Oct1509 06:56 AM
jtbell

1 
597 
Hi,
I am just curious; do EM waves attenuate in a vacuum? If yes, how does this happen? Also, how do they faint...

Oct1509 04:34 AM
sophiecentaur

17 
6,463 
Why is it more difficult , in terms of generating speed, to hit back a ball traveling slowly than one traveling fast?...

Oct1509 04:31 AM
sophiecentaur

21 
2,303 
In general, a good absorbers of radiation are also good emitters.
In commonsense, something that is should be a poor...

Oct1409 11:58 PM
Born2bwire

3 
2,789 