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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,618 
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 
507 
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 
592 
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 
626 
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 
411 
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 
395 
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 
416 
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 
1,142 
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 
416 
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 
547 
Does anyone have a link to an experiment (preferably fairly modern) which either supports or falsifies Prevost's...

Jul2114 07:10 AM
UltrafastPED

1 
528 
What are the physical interpretations of ##\mu_0## and ##\varepsilon_0##, the magnetic permeability and electric...

Jul2114 04:52 AM
PhilDSP

7 
583 
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 
588 
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 
497 
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 
395 
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 
1,189 
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 
494 
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 
910 
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 
1,169 
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 
888 
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 
1,139 
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 
4,700 
If I have 10m lever with a center of the mass 2m from the right side it must mean the shorter arm have greater mass to...

Jul1914 12:13 AM
Simon Bridge

1 
677 
Hello PF!
This is my first post in a while, and I am pretty excited to hear what you guys think about my idea. I...

Jul1814 01:36 PM
cnafets

2 
610 
How does one think about, and apply, in the classical mechanical Hamiltonian formalism?
From the Lagrangian...

Jul1814 11:44 AM
bolbteppa

0 
604 
For an IP67 rating (http://en.wikipedia.org/wiki/IP_Code), an electrical enclosure must be submerged to 1m for 30...

Jul1814 09:25 AM
SteamKing

1 
579 
I was wondering if somebody could let me know if wings inside of a closed environment (tube of sorts) with air flowing...

Jul1814 07:26 AM
.Scott

4 
735 
Hello.
Have you ever seen this experiment? https://www.youtube.com/watch?v=K9jRztEQ06o
OK, i know why does the...

Jul1814 04:52 AM
Oomph!

2 
1,127 
Hello so I just want to make sure I Am doing this correctly. also I know there is a magnetic field force formula....

Jul1814 02:17 AM
Ziggey

6 
1,061 
I am well aware that objects of varying masses, shapes, and surface areas will fall at different speeds and...

Jul1714 05:51 PM
Cosmic Al

4 
1,175 
Does Young's Modulus change with drastic changes in size? For example, suppose you exert a force on the micro scale or...

Jul1714 12:58 PM
Philip Wood

5 
922 
I am somewhat confused about the connection between divergence and solid angle for a beam. I know individually what...

Jul1714 08:26 AM
Naz93

13 
1,109 
I noticed this intriguing phenomena whilst messing about in work with a perfect glass hemisphere the other day:
...

Jul1714 07:13 AM
.Scott

2 
789 
Does "work done" actually have any real meaningful sense or value?
I've got no problem with "work done" when moving...

Jul1714 12:53 AM
atyy

5 
984 
what is the reason of soft xrays, Is it because when a accelerated electron approaches an atom the electrons'...

Jul1614 09:43 PM
UltrafastPED

15 
1,416 
Hello everyone,
I'm studying the finite strain theory and have come across the maximum dissipation principle. It...

Jul1614 08:09 PM
Chestermiller

3 
1,448 
Hi, I am a bit confused about what exactly is being produced when someone uses a hand generator. I know P=R(I^2). ...

Jul1614 07:14 PM
.Scott

3 
696 
Hi all,
I've been reading about biconvex lenses, drawing ray diagrams and real/virtual images. I'm now trying to...

Jul1614 03:11 PM
u0362565

2 
1,048 
Will a Venturi tube with the entry open to a moving fluid act the same as one that has a closed entry with a known...

Jul1614 10:54 AM
Bob Shapiro

0 
673 
Suppose the particle is at distance x from mean position and moving away . The standard formula for calculating...

Jul1614 08:24 AM
jtbell

32 
2,452 
Hello everybody. I registered today in this forum and this is my first post.
I'm Italian, therefore sorry for my...

Jul1514 10:41 PM
Cosmic Al

13 
1,419 