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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
48,268 
After studying the methods of Lagrange and Hamilton for a bit I still find myself uneasy about the action. I don't...

Jul2814 06:24 PM
Delta Kilo

16 
824 
How earth is considered to inertial frame of reference?

Jul2814 04:20 PM
olivermsun

3 
273 
Hello,
In an electric circuit, let's say we have a resistor and a generator(Voltage source). The electric field...

Jul2814 05:59 AM
tonyjk

22 
854 
The following is my take on friction. I wish to verify if my hypothesis is correct.
When trying to visualize...

Jul2714 11:24 PM
DeltaČ

7 
648 
Are there any experiments or theories about the relation between magnetic dipole moment orientation and velocity...

Jul2714 08:02 PM
carrz

4 
391 
Hello, everyone.
I saw this experiment: https://www.youtube.com/watch?v=klt9PNuqMC8
A man is doing experiment with...

Jul2714 04:32 PM
davenn

1 
265 
Just a quick question. Let A and B be two points. Electrical work is defined as the amount of energy it takes to move...

Jul2714 01:10 PM
FallenLeibniz

17 
729 
Two part inquiry
PART I
Situation: I have a Bfield and i'm pulling a straight piece of wire through that...

Jul2614 07:38 PM
iScience

2 
344 
Does all the light entering our eyes converge to a single point on the retina (assuming minimal aberration)? If this...

Jul2614 10:14 AM
ViolentCorpse

27 
2,106 
Hello everyone,
I was wondering how one would calculate the threedimensional charge density (per volume) in a...

Jul2514 09:32 PM
Born2bwire

3 
450 
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 
1,625 
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 
533 
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 
822 
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 
696 
Hi,
Just wanted to know the difference between permittivity and permeability.
As far as I researched, permittivity...

Jul2514 04:10 AM
vanhees71

1 
351 
If photons are oscillating electric and magnetic fields, then we should be able to deflect photons trajectories by...

Jul2514 02:19 AM
carrz

4 
639 
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 
404 
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 
416 
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 
486 
Good morning PF,
I am having some difficulty finding info on calculating a composite moment of inertia. The...

Jul2414 07:20 AM
jamesm

7 
1,190 
Hi, I was wondering about the interpretation of the Hamilton Jaccobi equation.
Naively we have H +...

Jul2414 03:51 AM
vanhees71

1 
573 
What happens when charge enters the resistor?

Jul2414 12:04 AM
kartikwat

6 
648 
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 
818 
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 
557 
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 
611 
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 
790 
Hello,
It is my understanding that a moving magnetic can induce an electrical current, and that conversely, and...

Jul2214 01:19 PM
Tord

3 
1,706 
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 
750 
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 
787 
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 
884 
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 
587 
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 
567 
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 
580 
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 
1,555 
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 
578 
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 
754 
Does anyone have a link to an experiment (preferably fairly modern) which either supports or falsifies Prevost's...

Jul2114 07:10 AM
UltrafastPED

1 
719 
What are the physical interpretations of ##\mu_0## and ##\varepsilon_0##, the magnetic permeability and electric...

Jul2114 04:52 AM
PhilDSP

7 
783 
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 
805 
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 
683 