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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,659 
So are newton's laws also an approximation to quantum phenomena. Can it be derived from quantum laws?

Aug2613 01:45 PM
Khashishi

11 
1,242 
I am having few doubts regarding pulley,strings and tensions .
The doubts are
1)Can a massless pulley rotate ?...

Aug2513 11:00 AM
Tanya Sharma

35 
4,318 
I'm studying magnetism from my textbook, and I have several doubts.
1. Magnetic flux in my textbook is defined as...

Aug2313 01:32 PM
marcusl

22 
1,277 
Problem: A nuclear generator produces energy used to accelerate a rocket. Given energy and mass, what is the...

Aug2113 11:09 PM
eigenperson

2 
610 
According to a physics gre book (Conquering Physics GRE by Kahn &Anderson), electric 'monopoles do not radiate'. They...

Aug2613 06:42 AM
sophiecentaur

9 
800 
So in Resnick & Halliday, it explains that the drift speed, or the average speed of charge moving in a wire under the...

Aug2313 01:03 PM
Khashishi

18 
1,189 
In an adiabatic process PVγ=constant
Now I thought the work done by an ideal gas in an adiabatic process was given...

Aug2513 02:33 PM
CAF123

3 
836 
After studying more complicated electronics, I find myself asking this question  'Why capacitor works?'
Why does...

Aug2213 11:23 AM
Khashishi

5 
523 
Hello,
Is there a cheap device or someone that I can easily build that will let me know the speed of a moving object?...

Aug2513 08:29 AM
DaleSpam

23 
1,391 
Hello all,
I've got an optics problem that I'm having some difficulty with, where I want to send a beam through a...

Aug2313 01:07 PM
Andy Resnick

7 
560 
Greetings,
This question makes reference to the stat mech book, “Fundamentals of Statistical and Thermal Physics”,...

Aug2613 03:19 PM
BruceW

11 
730 
I am working in classical mechanics. A planet is orbiting a star. The planet has a given velocity and a position...

Aug2313 10:14 PM
tfr000

6 
681 
Can we talk about the chemical potential of a system with fixed number of particles? Is this physically meaningful?...

Aug2213 10:17 AM
jfizzix

2 
500 
I just can't get why for a massless inextensible string passing around a frictionless pulley we easily take T1=T2 (in...

Aug2313 01:37 PM
PhanthomJay

9 
1,185 
Quaternions are new to me, so I constructed a simple model to help grasp the concept. I have a very simple dynamic...

Aug2213 11:52 PM
D H

10 
781 
I am doing a simple thermodynamic analysis. Couldn't get thermodynamic values (such as internal energy, exergy, and so...

Aug2213 03:56 AM
hymeme

2 
436 
why are we considering speed is constant to find velocity a particle in uniform circular motion, is it possible for a...

Aug2213 06:39 AM
bobydbcn

4 
399 
I am having a tough time understanding the principle of least action and I would really appreciate it if someone would...

Aug2313 02:21 PM
chris gray

3 
381 
Hi,
I've been looking at some animations of plane waves, and I really cannot see why a plane wave's electric field...

Aug2413 07:49 AM
frogguy

2 
368 
How do you solve the Kepler Problem for a 2body system where m1<<m2 with a given velocity and position vector...

Aug2313 11:51 PM
SteamKing

5 
547 
There is a new automated people mover (APM) opening in Porto Alegre, Brazil called Aeromovel; it is built using...

Aug2313 07:20 PM
tjej

5 
486 
I am trying to find out more about these devices. In particular, how to model them. In other words, can one use a...

Aug2213 01:41 PM
MikeO

0 
325 
Hi Guys,
In a lot of books dealing with spectroscopy, correlation functions or any kind of functions involving time...

Aug2313 09:15 PM
Steve Drake

2 
680 
Greetings, physicists and others, who just happen to understand physics. Something is bothering my mind again and I am...

Aug2413 01:04 PM
baudrunner

6 
534 
I have read that the rear surface reflection of a halfsilvered mirror undergoes no phase shift. But they caution that...

Aug2513 12:46 PM
Alfred Cann

1 
453 
It is known, that perpetum mobile of the second kind does not exist. This means, ff temperature is everywhere the...

Aug2513 06:33 AM
mfb

3 
450 
Hey there, I'm new! :D
The weight, which is mass according to the gravity, and this scalar force keeps the object...

Aug2513 04:22 AM
Nugatory

3 
508 
Simple question but I've never been through the proofs to know what I'm plugging into.
Are these components of the...

Aug2513 01:04 PM
SteamKing

2 
525 
The task is to calculate the force acting on a 50 meter long currentcarrying wire due to earth's magnetic field. The...

Aug2513 12:58 PM
eroxore

2 
772 
Hey guys, I'm wondering how come if we're in a completely dark room and shine a laser beam at an object, we see the...

Aug2613 10:55 AM
sophiecentaur

5 
844 
Hi
The thermo problem is as follow:
I have a fireplace and I have an underfloor water pipe heating. currently the...

Aug2613 05:53 AM
Ossdon

2 
330 
Hello,
I was being taught AC in High School, It was good but the way they taught us DC, things like drift velocity,...

Aug2713 05:55 AM
vanhees71

9 
755 
I had a question :
Heat energy was supplied to melt ice at 15 degree Celsius. But it was not enough to turn the...

Aug2613 04:16 PM
Andrew Mason

4 
466 
I red a classical mechanics concept in a book. Imagine that we have two observers with two frames of reference F1 and...

Aug2613 06:30 PM
Simon Bridge

1 
445 
A red a book in classical mechanics , the author says A particle is an idealised body that occupies only a single...

Aug2613 10:17 PM
Khashishi

3 
439 
The thermal energy comes from the translational kinetic energy right? The relationship between the two being...

Aug2613 06:42 PM
Andrew Mason

3 
491 
In a twobody solution ( Kepler Problem) how do you find the Lagrangian, L, if the position vector is:
x = (v_x * t...

Aug2713 03:56 AM
Philosophaie

7 
616 
I'm reading through these notes on numerical hydrodynamics. On pg17, they introduce the monotonized central difference...

Aug2613 02:45 PM
nicksauce

0 
351 
how can i calculate the require time for an airconditioning unit to cool from 30 degree celcius to 22 degree celcius?...

Aug2713 11:22 AM
russ_watters

6 
579 
Hello,
I was reading articles about EMR and health and I realized I never got how "output power" is related to...

Aug2713 02:12 PM
Drakkith

1 
548 