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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,891 
Hi, I am having trouble with the following:
...

Aug1209 03:40 PM
kuruman

3 
3,001 
Ok, this question may sound stupid to some. But still, I 'll ask.
In electrostatics we frequently discuss,...

Aug1209 01:01 PM
Bob S

6 
664 
From dimensional analysis, the speed of water waves can be determined as follows:
Only the gravitational constant...

Aug1209 12:52 PM
RedX

2 
664 
Hi,
Can somebody point me to a good explaination and theoretical background on neartofar fields tranformation....

Aug1209 11:14 AM
aro

6 
858 
Out of curiousity, I am wondering what happens, theoretically of course, if we place a 1.5V AC light bulb (which do...

Aug1109 09:03 PM
russ_watters

10 
2,633 
Why is the b field inside a thick toroid largest along inner edge and smallest along outer edge?

Aug1109 08:16 PM
Bob S

6 
1,002 
I'm trying to find out which logical statement is true.
If and only if there is a region of space where there is no...

Aug1109 05:21 PM
Maxwellkid

7 
892 
What is voltage? So many words, so many explanations are just hollow echoes off the walls of "authoritative sources" ...

Aug1109 03:30 PM
Red_CCF

48 
47,026 
So I was looking at MIT iTunes U physics videos, and the professor talked about regimes I and II in the video about...

Aug1009 06:51 PM
Phrak

5 
835 
Why do we not consider quantum effects when we deal with motion of electrons in a Cathode Ray Oscilloscope, or in a...

Aug1009 07:14 AM
manofphysics

2 
646 
It's evident that ampere's law is used to calculate the magnetic field produced by flowing charges. Can I use Gauss's...

Aug1009 07:05 AM
maverick280857

10 
2,714 
The thread title is meant to be "Can a fly lift a balloon", it's Tom now due to a small mistake while posting.
This...

Aug1009 05:09 AM
I_am_learning

7 
665 
If I'm in one of those carnival rides that spin fast I can feel the centrifugal force. This is due to the radial...

Aug1009 03:31 AM
A.T.

19 
2,711 
Hi,
When a circular section object (cylinder, sphere of radius r) rolls down an inclined plane (at angle theta) it...

Aug1009 03:20 AM
rcgldr

14 
19,429 
newbie question, say i'm rolling a ball down a smooth , differentiable, and frictionless 1Dimensional hill V(x) from...

Aug909 06:37 PM
bm0p700f

6 
4,374 
Hello !
Is there an expression for the friction force exerted on a solid sphere rolling (or rolling and slipping) on...

Aug909 06:17 PM
bm0p700f

14 
5,118 
Q1. A thermometer is laid out in direct sunlight. Does it measure the temperature of the air, or of the sun, or of...

Aug909 01:29 PM
dx

15 
4,372 
anyone have equations for bitter magnets? or do i use the ones for solenoids?
i need an electromagnet capable of...

Aug909 05:20 AM
microfracture

7 
3,921 
Hello, all!
I am currently working with the governing equation of a rotating, translating rigid body. That is:
...

Aug909 12:54 AM
Arrowstar

0 
828 
I've been reading through the Feynman lectures (almost done with Volume 1), and I have been trying to prove everything...

Aug809 12:44 PM
Bob S

3 
1,729 
Hi, I have some questions about the derivation of the Boltzmann distribution, for instance as in Mandl's "statistical...

Aug809 10:49 AM
haushofer

6 
1,457 
if a body that is going in space in a straight line and suddenly 2 forces acts on it the first with the motion...

Aug809 12:38 AM
rcgldr

20 
1,618 
I wanna know whether this analysis in the image is correct or no ,and if no pleas I want u to explain me the reason...

Aug709 08:38 PM
Doc Al

4 
756 
Hi
I'm looking for a place were I can find the damping coefficient for water. Maybe someone has/can find/knows a...

Aug709 02:55 PM
nasu

5 
14,242 
Recently I was asked whether the concept of a statistical ensemble is actually realistic and I recognized that I can...

Aug609 07:34 PM
Mapes

1 
700 
So, the rocket equation is
F_ext = m(dv/dt) + u(dm/dt)
where m is the mass of the rocket, v the velocity, u the...

Aug609 02:03 PM
Nabeshin

1 
1,738 
Hi,
I want to electrically heat a uniform block of a known material to a high temperature (about 2000 K). I want to...

Aug609 05:59 AM
phyzzy_physh

4 
939 
It is said that if a force depends only on distance (And not on time), the equations that involve those forces are...

Aug609 05:26 AM
Jano L.

1 
973 
I am looking for a relation between electromagnet (or permanent magnet) and frequency.For example what is the...

Aug609 03:27 AM
vin300

3 
846 
Hi friends,
long time ago I noticed the following interesting similarity between
classical mechanics and...

Aug509 03:53 PM
Jano L.

0 
907 
Suppose you're driving along a straight, smooth, level stretch of highway with a constant velocity v. There is a cup...

Aug509 02:46 PM
jpreed

1 
633 
i am so confused.. does anybody know a good source to learn physics? every single source (book, website, etc.) says...

Aug509 02:25 PM
Mad_Eye

10 
2,012 
Hello, I got another inquiry about work. Supposing an external agent gives potential energy to an object by pulling it...

Aug509 12:19 PM
rcgldr

8 
832 
Why is the normal reaction to a rolling object shown to the side of the CM?
Forces must be equal and opposite
Is...

Aug509 12:05 PM
rcgldr

6 
1,080 
I understand that light propagates as a transverse wave  does this mean that the momentum carried by a photon is...

Aug509 11:28 AM
Bob S

2 
1,145 
I'm new to these equations but let's see if I have the talk down.
1. The electric field surrounding a charge will...

Aug509 10:57 AM
Born2bwire

18 
1,597 
Can a generic, not necessarily harmonic, signal of time be represented as a complex signal with a real and imaginary...

Aug409 11:50 AM
jasonRF

4 
3,159 
Suppose some vehicle with mass m is moving down a hill with angle \theta . Say that the vehicle is exerting a...

Aug409 10:27 AM
sganesh88

20 
3,964 
What is the actual definition of the TM mode? A typical definition that I've come across is that there is no Magnetic...

Aug309 10:15 PM
Born2bwire

2 
2,371 
I've been thinking about this problem today. I tried reasoning my way through it and I haven't been able to. I might...

Aug309 05:45 PM
J Goodrich

2 
586 