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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,835 
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 
626 
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 
2,624 
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 
649 
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 
2,679 
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 
19,255 
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 
4,294 
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 
5,050 
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 
4,265 
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 
3,856 
Hello, all!
I am currently working with the governing equation of a rotating, translating rigid body. That is:
...

Aug909 12:54 AM
Arrowstar

0 
794 
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 
1,708 
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 
1,437 
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 
1,582 
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 
751 
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 
14,055 
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 
690 
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 
1,707 
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 
918 
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 
955 
I am looking for a relation between electromagnet (or permanent magnet) and frequency.For example what is the...

Aug609 03:27 AM
vin300

3 
834 
Hi friends,
long time ago I noticed the following interesting similarity between
classical mechanics and...

Aug509 03:53 PM
Jano L.

0 
873 
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 
626 
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 
1,975 
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 
816 
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 
1,065 
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 
1,126 
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 
1,575 
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 
3,133 
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 
3,870 
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 
2,356 
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 
580 
can circular magnetic fields accelerate charged particles linearly?
is their any method to make a powerful circular...

Aug309 05:43 PM
Bob S

22 
2,489 
Recently, there was a thread on Reddit titled "The year is 2035. We have a permanent base on the moon and have sent...

Aug309 01:48 PM
ZapperZ

14 
1,297 
I understand the the specific heat capacity of a material is a function of temperature.
Does anyone know of either...

Aug309 07:51 AM
lalbatros

2 
1,055 
how to calculate the amount of voltage, current and power that two junctions can produce with seebeck effect when the...

Aug309 06:54 AM
aravindnaga

0 
1,009 
Hi,
I have been trying to model the temperature distribution along the length of a fin.
With a constant 'h',...

Aug209 09:41 PM
Karthiksrao

2 
654 
Hello, this is my first post, i hope somebody can help me.
I have searched for the answer myself all over on the web...

Aug209 08:54 PM
Q_Goest

5 
4,347 
hi all,
i think this should be simple but i just cant figuring it out
i basically want to move a particle at...

Aug209 05:51 PM
rcgldr

8 
1,394 
Hello, I've been going over work and energy transfer for some upcoming tests, and I got the following question:
...

Aug209 07:29 AM
Perrin

2 
560 
If you have just one point charge of 1 Coulomb in the entire universe, and you look at the magnetic field at a foot...

Aug109 12:11 AM
rockyshephear

15 
1,120 