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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,017 
Let's suppose i want to send a message over really big (interplanetary, maybe out of the solar system) distances.
I...

T 01:08 PM
GTOM

26 
1,041 
What does p = mv really mean? For example, why is there a physical law based upon the product of mass and velocity?...

T 11:37 AM
vjacheslav

4 
176 
Hello.
I'm having trouble with determining the dynamics of a rod, when one of the ends has a torque applied to it....

T 09:31 AM
Orodruin

13 
138 
Just a quick question. Let A and B be two points. Electrical work is defined as the amount of energy it takes to move...

T 09:29 AM
DeltaČ

16 
218 
Today I was taking the train to a nearby city, where we passed through some rainy region.
As the raindrops fell on...

T 08:55 AM
Andy Resnick

3 
331 
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...

T 08:42 AM
Andy Resnick

3 
235 
Does all the light entering our eyes converge to a single point on the retina (assuming minimal aberration)? If this...

T 06:36 AM
ViolentCorpse

25 
871 
Hi,
Just wanted to know the difference between permittivity and permeability.
As far as I researched, permittivity...

T 04:10 AM
vanhees71

1 
68 
After studying the methods of Lagrange and Hamilton for a bit I still find myself uneasy about the action. I don't...

T 03:22 AM
vanhees71

4 
136 
If photons are oscillating electric and magnetic fields, then we should be able to deflect photons trajectories by...

T 02:19 AM
carrz

4 
179 
When studying about semiconductos what are the valence band and conductivity band .what are its properties,where is it...

T 12:06 AM
e.bar.goum

1 
76 
The following is my take on friction. I wish to verify if my hypothesis is correct.
When trying to visualize...

Y 11:11 PM
Travis091

1 
97 
I have just completed reading an English translation (The Great Books version) of Newton's Principia and found it...

Y 12:18 PM
dkotschessaa

2 
77 
Hello.
I saw this experiment: https://www.youtube.com/watch?v=hBQ8fh_Fp04
The light from laser is bending in small...

Y 09:24 AM
jtbell

3 
95 
Good morning PF,
I am having some difficulty finding info on calculating a composite moment of inertia. The...

Y 07:20 AM
jamesm

7 
526 
Hi, I was wondering about the interpretation of the Hamilton Jaccobi equation.
Naively we have H +...

Y 03:51 AM
vanhees71

1 
185 
What happens when charge enters the resistor?

Y 12:04 AM
kartikwat

6 
186 
Is there a mathematical relation for the temperature change when a fluid flows through a pipe from one end to another?...

Jul2314 06:14 PM
Jay_

37 
5,377 
Consider a light, an L.E.D for example, turning on and off once per second. For humans, we will look at it and think...

Jul2314 01:43 PM
rcgldr

4 
219 
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 
326 
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 
164 
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 
420 
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 
219 
What is voltage and how to look at it intellectually?

Jul2214 09:27 PM
jim hardy

30 
1,975 
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 
321 
Hello,
It is my understanding that a moving magnetic can induce an electrical current, and that conversely, and...

Jul2214 01:19 PM
Tord

3 
1,006 
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 
302 
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 
296 
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 
361 
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 
398 
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 
231 
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 
214 
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 
213 
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 
797 
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 
226 
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 
315 
Does anyone have a link to an experiment (preferably fairly modern) which either supports or falsifies Prevost's...

Jul2114 07:10 AM
UltrafastPED

1 
305 
What are the physical interpretations of ##\mu_0## and ##\varepsilon_0##, the magnetic permeability and electric...

Jul2114 04:52 AM
PhilDSP

7 
367 
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 
364 
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 
314 