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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,003 
Let's suppose i want to send a message over really big (interplanetary, maybe out of the solar system) distances.
I...

Jul2514 01:08 PM
GTOM

26 
1,499 
Hello.
I'm having trouble with determining the dynamics of a rod, when one of the ends has a torque applied to it....

Jul2514 09:31 AM
Orodruin

13 
450 
Today I was taking the train to a nearby city, where we passed through some rainy region.
As the raindrops fell on...

Jul2514 08:55 AM
Andy Resnick

3 
711 
Why is it that the width of a wire grid polarizer has to be less than the wavelength of the wave which I want to...

Jul2514 08:42 AM
Andy Resnick

3 
573 
Hi,
Just wanted to know the difference between permittivity and permeability.
As far as I researched, permittivity...

Jul2514 04:10 AM
vanhees71

1 
311 
If photons are oscillating electric and magnetic fields, then we should be able to deflect photons trajectories by...

Jul2514 02:19 AM
carrz

4 
516 
When studying about semiconductos what are the valence band and conductivity band .what are its properties,where is it...

Jul2514 12:06 AM
e.bar.goum

1 
337 
I have just completed reading an English translation (The Great Books version) of Newton's Principia and found it...

Jul2414 12:18 PM
dkotschessaa

2 
343 
Hello.
I saw this experiment: https://www.youtube.com/watch?v=hBQ8fh_Fp04
The light from laser is bending in small...

Jul2414 09:24 AM
jtbell

3 
370 
Good morning PF,
I am having some difficulty finding info on calculating a composite moment of inertia. The...

Jul2414 07:20 AM
jamesm

7 
1,002 
Hi, I was wondering about the interpretation of the Hamilton Jaccobi equation.
Naively we have H +...

Jul2414 03:51 AM
vanhees71

1 
494 
What happens when charge enters the resistor?

Jul2414 12:04 AM
kartikwat

6 
559 
I'm stuck on some highschool physics, Gauss law...
1. It says this: The electric field outside the sphere is equal...

Jul2314 10:57 AM
Satvik Pandey

6 
708 
This is a question we were asked quite some time ago:
Consider a circuit shaped as a rectangle, with two very long...

Jul2314 09:26 AM
Nugatory

2 
470 
Many of you are familiar with the catapult launched profile fuselage gliders that are sold in hobby stores. Since...

Jul2314 08:18 AM
Simon Bridge

13 
801 
There is a silly detail about the interpretation of the Van der Waals (VDW) equation that I cannot fully understand....

Jul2314 07:51 AM
atyy

3 
521 
I want to describe the motion of a ball that rolls without slipping in a plane where acts a force field not in the...

Jul2214 03:54 PM
jaumzaum

4 
673 
Hello,
It is my understanding that a moving magnetic can induce an electrical current, and that conversely, and...

Jul2214 01:19 PM
Tord

3 
1,546 
Consider a circular loop of radius R that carrys a uniform current I. We know(by BiotSavart law) that the magnetic...

Jul2214 09:01 AM
vanhees71

6 
638 
I was wondering why is there a minus sign in the equation:
EMF= d(flux)/dt
If this equations is derived from a...

Jul2214 08:59 AM
vanhees71

6 
646 
We know that a steam power plant is basically a heat engine with steam as the working fluid.
According to the...

Jul2214 08:14 AM
enorbet

3 
704 
Let me set the stage for a thought experiment.
1. A physicist in an elevator at some arbitrary height above Earth...

Jul2214 05:05 AM
A.T.

7 
744 
Hi, can someone please help me on this problem. I'm not sure what to do with the equation given. I tried taking the...

Jul2114 09:20 PM
Matterwave

1 
496 
Why the torque is called moment of force and angular momentum is called moment of linear momentum ? Please explain.

Jul2114 09:12 PM
Matterwave

1 
483 
What is meant by moment of particles ? Why the algebraic sum of moments of all particles about centre of mass must be...

Jul2114 09:10 PM
UltrafastPED

2 
498 
When I fire a gun there is an explosion inside a barrel that causes bullet to fly and gun to recoil but when a barrel...

Jul2114 05:32 PM
enorbet

17 
1,339 
Hello,
Someone could explain me why in the derivation below the mass m is divided by 2 in the last step?:
...

Jul2114 03:01 PM
jbriggs444

1 
498 
Hello,
I know that the latent heat of a firstorder isothermal and isobaric phase transition is in general given by...

Jul2114 10:24 AM
g_mogni

3 
641 
Does anyone have a link to an experiment (preferably fairly modern) which either supports or falsifies Prevost's...

Jul2114 07:10 AM
UltrafastPED

1 
611 
What are the physical interpretations of ##\mu_0## and ##\varepsilon_0##, the magnetic permeability and electric...

Jul2114 04:52 AM
PhilDSP

7 
672 
For a glider to sustain flight at a constant speed, the aircraft must be placed in a dive so that the forward motion...

Jul2114 02:39 AM
CWatters

6 
680 
I'm having a brain fart so this is just another silly question but...
when deriving the IV relation for the...

Jul2114 01:59 AM
iScience

4 
570 
Hi experts!
Im new in this forum.
Im studying a cylinder of radius (A) very small compared to its length (L)....

Jul2014 02:30 PM
mresimulator

0 
473 
Of course I am sure this is not a paradox but rather a problem in my understanding of the situation.
But this...

Jul2014 02:29 PM
Drakkith

23 
1,361 
hi guys
I am attempting to solve a problem that has me scratching my head. I have a small connector PCB with one...

Jul2014 03:33 AM
CWatters

1 
566 
Hello.
I have two simple questions.
1) I don't understand atmospheric force. I read that it occurs by heaviness of...

Jul2014 01:39 AM
DeltaČ

2 
1,050 
I am trying to understand the Coriolis effect from some time but i am unable to conceive the idea why the air parcel...

Jul1914 12:05 PM
Arfur Bryant

16 
1,254 
I have a doubt that can we increase the intensity of light without changing its amplitude and by increasing its...

Jul1914 08:48 AM
Claude Bile

4 
970 
Hello again,
My handy optics engineer has left the country leaving me with a problem that's over my head. I need...

Jul1914 08:42 AM
Claude Bile

5 
1,221 
This question has been asked probably many times, and is inspired by area that appears in denominator of energy flux...

Jul1914 07:40 AM
DaleSpam

35 
4,981 