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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
48,251 
Is the kinetic energy of a (not necessarily homogeneous) rigid body in translational motion and rotating about its CM...

Nov1206 01:00 AM
jtbell

10 
10,096 
Can somebody explain to me the differences between the ensembles, and how does this differences refer to experiment?
...

Jan2911 03:58 PM
paweld

1 
10,091 
Hello,
I have a quick question that I imagine anyone who has studied physics or math at a university can answer...

Jan1312 06:46 AM
Claude Bile

48 
10,084 
From experiment, it's easy to see that if we balance an industrial sized broom with one finger at it's center of...

Jan407 06:14 PM
PhysMaster

7 
10,058 
I've attached a diagram of a bar magnet being plunged into a solenoid.
I'd like someone to explain the direction of...

Jan2312 08:08 AM
mishi003

7 
10,054 
Hello.
I'm having troubles solving the enthalpy for an ideal gas.
From the equation H=U+PV, i could find H...

May1510 08:41 AM
quantoshake11

2 
10,044 
Hi, has anybody worked with heat pumps? I'm recently confused about how the heat pump compressor operates. Does it...

Jan2111 01:22 AM
ikhlaq

5 
10,033 
Permanent magnets are advertised as having some scalar strength, say, 1.5 Teslas, depending on the composition of the...

Mar1809 08:34 AM
clem

5 
10,031 
There's a simple explanation that wasn't covered in the last thread about this.
Start off with an ideal...

Nov607 11:49 PM
ael65

3 
10,025 
So, I have a few questions regarding some of the laws of electromagnetism.
While I was in school, one of my...

Nov909 02:28 PM
Bob S

17 
10,023 
Hi,
From knowing that the 3D harmonic oscillator has 3 degrees of freedom, how do you conclude that the average total...

Sep2909 07:43 AM
conway

15 
10,020 
What are you able to derive or integrate from a voltage vs. time graph? Like if I have a battery and a resistor and...

Oct2109 03:15 AM
mikelepore

4 
10,019 
Say we have a simple circuit with just a battery and two capacitors. Why must the voltage of each capacitor in series...

Feb1609 10:02 PM
atyy

3 
9,970 
Evryone knows that the work done by a magnetic field is zero. Then how does a permanent magnet lift iron filings.

Aug604 10:13 AM
rayjohn01

31 
9,965 
While I understand the use of the Lagrangian in Hamilton's principle, I have the gut feeling that there is more to it...

Sep2904 10:12 AM
alexepascual

43 
9,921 
Hello physics forum crew, I would like some help coming up with one of those "is this possible" type questions.
...

Jul1912 09:54 AM
Darwin123

129 
9,912 
Is the amount of energy needed to raise the temperature of a substance linear or not? For instance, would it take the...

Jan1004 02:38 AM
Bystander

13 
9,911 
Hey can neone tell me why this is so? I have not got the ans in any book i read...
Thnx 4 replying

Jun1708 09:37 AM
Count Iblis

8 
9,909 
I am having trouble going about proving the Lorentz invariance and nonGalilean invariance of Maxwell's equations. ...

Nov2707 03:13 AM
Mentz114

4 
9,884 
Mass on a string undergoing uniform circular motion by hand:
I was taught that the centripetal force F = mV^2/R is...

Feb510 01:27 AM
rcgldr

7 
9,862 
is it, cause velocity isn't.

Jan1511 04:12 PM
Mueiz

60 
9,854 
I've been trying to derive the StefanBoltzmann law using thermodynamics, and have resorted to looking up the...

Mar1512 01:59 AM
Tub46542

20 
9,823 
I was just wondering if anyone has any idea on how I would go about working this out. I have performed the experiments...

Sep2808 09:35 AM
Redbelly98

5 
9,814 
I read that the speed of sound in air at 20 degrees celsius is about 1126 feet per second.
When I shoot my rifle,...

Sep2211 08:04 AM
DaveC426913

30 
9,808 
Hi!
Great website I just wished I had discovered it earlier. :smile:
Here is my simple question and I would...

Dec2309 05:38 AM
AzeemA

6 
9,792 
any good website suggested on coupled pendulum?
I have to do an investigation and I'm going to investigate simple...

Nov1703 03:33 PM
LLT

7 
9,780 
I am a bit confused when doing questions about 2 masses connected by a pulley system.
Sometimes i get the right...

Jun2010 11:46 PM
K^2

1 
9,771 
Could someone explain me in detail the differences between an inertial reference frame and a noninertial reference...

Jan1605 07:32 AM
marlon

3 
9,768 
i saw the 'proof' of the wave equation for a sound wave in a medium assuming the wave equation for a dissplacement...

Nov1707 09:49 PM
pardesi

0 
9,768 
Could someone please give me some examples of natural nonliving processes where entropy decreases locally ?
Now I...

Mar2611 06:10 AM
I like Serena

4 
9,760 
I have found a website which claims that rubber bands obey a force law
F=kT(x\frac{1}{x^2})
x=\frac{L}{L_0} ...

Oct2604 02:50 PM
PerennialII

6 
9,734 
I was wondering how quickly a permanent magnet would loose its magnetism if it was constantly being used to do work,...

Mar809 07:20 PM
russ_watters

24 
9,716 
I'm having trouble understand this proof of Carnot's theorem, and I would appreciate it if someone could point out...

May1513 10:10 AM
Swarnali Hait

4 
9,709 
Our local YMCA is putting on an indoor triathlon and I am trying to come up with a formula to help them determine the...

Mar1611 11:11 AM
Rap

13 
9,709 
Hi
I have a hard time understanding what the curl really means in Maxwell's equations, for example in a steadystate...

Mar606 05:41 AM
dextercioby

10 
9,704 
Hello all.
I am doing some research on the space shuttle for a class project, and I am having some problems with my...

Jul1604 11:47 AM
JonasS

9 
9,702 
can the net force on an object be zero yet the velocity not be zero?
I say yes but under what conditions and must any...

Jun405 06:12 PM
paulom2001

12 
9,702 
Hi All,
I'm doing a study on effects of outside temperature on the energy efficiency of airconditioning systems in...

Feb2610 07:33 PM
russ_watters

5 
9,702 
As water is pulled into an opening by gravity, it begins to spin. Why does it spin?

Apr2108 01:34 AM
kamerling

34 
9,695 
Okay, im new so if what im talking about makes no sense, be easy...i dont really know if it belongs in classical...

Mar2609 11:20 PM
Eidnar1

22 
9,686 