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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,690 
Not knowing enough math to be able to understand the equations I nevertheless wonder how c is able to magically...

Sep1911 08:53 AM
vanhees71

8 
1,629 
In an isobaric expansion process, the pressure of the gas is kept constant. Because of the increase in volume the...

Sep1911 12:03 AM
Andrew Mason

1 
1,228 
I have a hard time conceptualizing string tension, and hence calculating it.
For a hypothetical situation, there is...

Sep1811 07:39 PM
Ken G

10 
19,436 
I am trying to develop a game of carrom board.
For this i want to know how to find contact time if Coefficient of...

Sep1911 08:16 PM
Freeze3018

2 
1,030 
How exactly does the bores of a connecting rod turns oval and how can you measure the ovality and determine if it is...

Sep1811 09:16 AM
renjith_p

0 
2,666 
I have attached a figure with this, to help in understanding the problem.
A ring whose circumference is attached to...

Sep1711 06:07 PM
vishal007win

0 
978 
So as you all know, kinetic energy is..
K=\frac{1}{2}mv^2
The question I have is the followng.
The "v" in this...

Sep1811 05:13 PM
jtbell

3 
908 
We have many harmonics in a string
http://img43.imageshack.us/img43/3452/dfshfghdfh.jpg
Why when we play a...

Sep1911 01:14 AM
JeffKoch

8 
1,682 
Suppose a box is sitting, motionless, on an inclined plane which makes an angle \theta with the horizontal. If I'm not...

Sep1911 10:38 PM
issacnewton

1 
1,215 
Hi,
Does anyone have a formula for the freezing time (ie time taken for it to freeze) of a fixed volume of water...

Sep1911 07:17 AM
xts

1 
956 
Hi All,
For a hydrogen atom in the field B, torque on the electron is \tau =\mu Bsin\theta =\omega_pJsin\theta =>...

Sep1911 08:36 PM
clem

1 
855 
Hi!
I am curious about two books which seem really great, but somehow I became sceptical of the authors. Are they...

Sep1711 04:37 AM
HotMintea

3 
3,483 
hi, i solve heat and mass transfer on flat plate. i found that in some cases the negative sherwood number occurs. i...

Sep1811 06:50 AM
samiyare

0 
1,199 
Gamma decays are e.m.waves ..then how describe gamma decay in terms of energy levels?

Sep1911 04:55 AM
xts

1 
949 
Is there a equation that calculate the energy of a wave acccording to the amplitude
Another question, The...

Sep2011 08:45 AM
nasu

3 
2,242 
The definitions of other units that doesn't depend on the kilogram are somehow constants, like the speed of light, the...

Sep2011 07:09 AM
f95toli

13 
1,526 
Hi everybody,
I am using a ultrasonic water bath cleaner in one of my experiments.
It is basically a container...

Sep1911 09:42 AM
lupok2001

0 
549 
In the ferroelectric literature, thermodynamic potentials are often written in terms of electric polarization P rather...

Sep1811 02:38 PM
johng23

0 
499 
Guitar strings behave like a spring when tuned:
F = k.x is the tension in the string, where k is the contant...

Sep1811 08:06 PM
olivermsun

3 
1,822 
My question is related to the gaussian surfaces, a planar conductor and an infinite sheet.
...

Sep1911 02:26 AM
Mike Dykes

7 
1,608 
I am really interested in accelerating some metal ions at home but don't really know where to start...
I am willing...

Sep1511 01:30 PM
xts

18 
2,872 
In Gamow's short book 'Gravity' he describes the effect of lunar gravity on the earth, in particular the seeming...

Sep1511 06:39 AM
A.T.

86 
8,427 
Hi!
I'm trying to find a way to use piezoelectric materials, and put them under floors or roads so that people's...

Sep1811 06:34 PM
Vanadium 50

33 
7,936 
what's special about a 0.1 to 0.2 volts current?
thanks

Sep1811 09:42 PM
jishitha

5 
989 
According to wikipedia, «inertia is the resistance of any physical object to a change in its state of motion or rest,...

Sep2011 05:30 AM
Ken G

49 
5,733 
Suppose you have a reaction wheel or a control moment gyroscope on your spacecraft for attitude control. This would be...

Sep1611 10:01 PM
Mordred

3 
1,379 
I don't quite understand how the law of conservation of energy applies to a hydroelectric dam, such as the one...

Sep1811 04:53 PM
rcgldr

31 
4,993 
Hi,
I am trying to keep a small vial of liquid cold (> 2 Celcius but < 8 Celcius) for 10 hours when the ambient...

Sep1911 05:06 AM
xts

9 
2,002 
Can there be a 100% rigid object i.e., an object that cannot be compresses any bit? I believe that's not possible. The...

Sep1611 02:03 AM
Curl

8 
1,747 
Hi there, my wife just asked me how hard the impact is when two sides of a rugby scrum come together. I think she's...

Sep1611 04:06 AM
Zacski

0 
1,369 
I'm doing a project regarding a canyon in the Big Bend National Park area. I'm supposed to be building an outpost on...

Sep1511 03:11 PM
redtemplepilo

0 
750 
Hi, I'm finished studying ondulatory and I have maany questions I still don't understand. I would be thankful if...

Sep1811 07:20 AM
Philip Wood

8 
1,146 
Hi Guys,
Suppose we have a spherical shell with charge density on the surface \sigma and radius R. The potential...

Sep1511 02:16 PM
dikmikkel

5 
2,146 
why is sound heard more clearly in night than at day?

Sep1511 04:22 PM
AlephZero

2 
1,167 
How can Ohm's law explain the fact that the resistance of a wire depends directly on length and inversely with area?

Sep1511 01:17 PM
berkeman

3 
1,171 
I was thinking about the Carnot Theorem, and thinking how that applies to a car's engine. T_hot would be the...

Sep1611 03:00 PM
Curl

23 
3,716 
I want a piece of iron which is painted exactly like the picture to simulate. The piece is made of iron, and before...

Sep1611 12:22 PM
lieuthnant

0 
1,775 
This is a very long argument between me and a supplier of a electric linear actuator for opening gates.
In the...

Sep1611 01:20 PM
Tmp

0 
1,233 
I am trying to understand the magnet and conductor problem that Einstein mentions at the beginning of one of his 1905...

Sep1811 05:26 AM
Philip Wood

4 
1,274 
Sorry if this is in the wrong category but I had an exam question today that I couldn't figure out.
The problem...

Sep1711 09:58 PM
klimatos

7 
1,281 