
Before posting anything, please review the Physics Forums Global Guidelines.
Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,900 
Its been 15+ years since I have done any calcs like this and am very rusty, so even just a pointer in the right...

Apr808 12:25 PM
Gordianus

1 
2,307 
From the 1st law of thermodynamics we have
dU = ∂Q+∂W
but we also know
dU = Tds  pdv ,
i am confused...

Apr808 07:48 AM
Hootenanny

1 
1,412 
For electromagnetic field we usually use the Lagrange's density
...

Apr708 08:24 AM
sweetser

44 
7,205 
Does anyone have an idea about a formula relating the refractive index of a medium
to the temperature gradient...

Apr708 01:43 AM
Relena

7 
2,114 
Anyway ... a long long time ago, my father told me a story how when he was in college, they used to heat water just by...

Apr708 12:39 AM
Shooting Star

6 
5,095 
i understand the reason and steps leading to the equation that relates acceleration in the inertial frame to...

Apr608 07:59 PM
bman!!

4 
1,454 
I raised this question in the courseware section and I got only one response. To improve the response, I am repeating...

Apr608 06:28 PM
Doc Al

1 
1,425 
I'm trying to explain to a coworker some fallacies in a thought problem he came up with that has severely confused him...

Apr608 02:56 PM
luben

9 
1,551 
hi
I'm a new poster here.the three body problem fascinates me a lot and was just wondering if there's any book out...

Apr608 09:56 AM
Jacob1983

0 
1,008 
ive just come across gauge transformations on maxwells equations, and mathematically its all pretty straightforward,...

Apr608 01:16 AM
Phrak

5 
1,471 
How does a magnetic field do work on the electrons in a wire?
If F = q v x B, the magnetic field is always...

Apr508 10:36 PM
Phrak

7 
1,843 
Hiya. I'm revising for a classical mechanics first year exam, and the lecture notes on central forces are less then...

Apr508 04:35 PM
cpfoxhunt

0 
803 
Can an electron's mass and its magnetic moment be measured in the same experiment?

Apr508 03:57 PM
David George

2 
1,143 
I would like to analyze the motion of a superball, heres what I have so far, the perpendicular(to the ground)...

Apr508 01:45 PM
SpitfireAce

0 
1,191 
As we know, the variational principle can be used as the fundamental principle of mechanics. Without knowing Newton's...

Apr408 08:18 PM
cstalg

4 
2,945 
Consider a wire, if I suddenly pass current on it. There would be an instant localized B field around the wire. Since...

Apr408 07:58 PM
enroger

4 
958 
In school yesterday I was doing a practical and when I moved a small 1.5T block magnet near a rheostat the magnet...

Apr408 05:21 PM
lugita15

1 
1,263 
Im studying for the Fundamentals of Engineering exam (coming up April 12!!) and came across this Thermodynamics...

Apr408 01:04 PM
Mapes

1 
1,099 
I wanna know if in rapid adiabatic compression of a gas, is work done by gas on surrounding (atmosphere) numerically...

Apr308 11:07 PM
zarbanx

14 
3,011 
Hi all,
One idle night a friend and I started an argument over the question:
"How much energy is imparted on to...

Apr308 06:06 PM
seycyrus

12 
9,280 
I know that as temperature increases the extension of a material under a specific load increases too, but what is the...

Apr308 12:00 PM
Andy Resnick

1 
1,199 
Hoping that someone on this forum can help me with this problem that has been stealing my sleep at night:rolleyes:
...

Apr308 11:13 AM
jacob_yukon

0 
636 
Do electrons flowing in a circuit perform work with their mass (or kinetic energy)? For example like a water flowing...

Apr208 10:44 PM
Snazzy

32 
6,902 
If you have the primary and secondary coils of a transformer next to each other, then current will induce a voltage in...

Apr208 03:13 PM
TVP45

3 
1,004 
if a system of particles is composed of n freely moving particles .is the mass of this system qual to the sum of the...

Apr208 01:41 PM
tarekkkkk

2 
894 
If you combine many small magnets together in a cube or spherical shape (say those 1.5 tesla rare earth magnets), is...

Apr208 10:03 AM
clem

4 
1,236 
I am a beginner in thermodynamics. I was going through a educational board's chapter on thermodynamics. I want to...

Apr208 08:05 AM
Andy Resnick

2 
1,079 
So, I am looking a question about adiabatic expansions and the associated entropy changed.
Why exactly is the...

Apr208 07:46 AM
Mapes

4 
1,056 
I was just wondering, since my textbook doesn't really explain it too well, what velocity is part of the equation F =...

Apr208 02:16 AM
Feldoh

13 
2,083 
When dealing with system containing millions of particles( for example, charged particles or magnetic particles) with...

Apr108 07:36 PM
pam

1 
1,032 
Hi there,
I'm working on some experiments regarding to gases. I want to know what'd happen to gas which is uneder...

Apr108 04:16 PM
russ_watters

9 
2,810 
The flux rule states that the emf induced in any loop is given by the rate of change of magnetic flux through that...

Apr108 03:00 PM
lugita15

4 
2,147 
Hi!
Can some one give me a link where i can find details about finding the velocity of propagation of a mechanical...

Apr108 12:17 PM
Andy Resnick

1 
2,359 
magnetic field forms closed loop always. So, it should be called a nonconservative force.
But if a charged...

Apr108 11:41 AM
i_island0

12 
3,052 
A revolving satellite is similar to a lift which is falling from a height. Only the difference is that the satellite...

Apr108 11:23 AM
YellowTaxi

6 
1,529 
Hi,
If I were to bring a magnet (just 1 mm long) close to a hypothetical "magnetic" black hole  something that has...

Mar3108 03:41 PM
rsr_life

0 
1,841 
This question came some time back in Stony Brooks exam. I have the solution also. But i am having some conceptual...

Mar3108 03:02 PM
zarbanx

2 
10,358 
Hi,
When a gas is compressed, its temperature increases. But what is the formula to calculate this rise? Could you...

Mar3108 02:38 PM
zarbanx

3 
17,096 
Hi there,
I am developing a really cool new product and it somehow relates to pressure's behavior. Since I do not...

Mar3108 12:26 PM
marcusl

1 
1,005 
Hi, I am wondering if anyone here has a way to calculate the surface temperature of an object as it gets hit by a...

Mar3108 10:57 AM
fair001

9 
3,632 