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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,892 
I know power is what causes devices to function in a circuit. What role does the voltage have in a circuit?

Sep2709 08:01 AM
sophiecentaur

3 
984 
Let's say I have a system with multiple oscillatory modes. Is it possible to have anything in this system that...

Sep2709 07:30 AM
thrillhouse86

3 
1,010 
I'm feeling a lot of difficulty in studying fluid mechanics..
can anybody please kindly suggest me a good book for...

Sep2609 08:43 PM
thrillhouse86

4 
2,425 
I'm a little confused on how the math is supposed to work out when you are adding an electric field from charges with...

Sep2609 05:01 PM
tinytim

5 
2,845 
Hi all,
I am doing a project on the speed limit on human sprinting. I was doing a thought experiment and then got...

Sep2609 03:48 PM
dimensionless

7 
1,497 
In the text, it is said that the polarization is just the response of the input electric field so they have
P =...

Sep2609 03:43 PM
KFC

3 
912 
Does a black hole radiate infrared waves? If not, then it could absorb some of the infrared waves from a colder...

Sep2609 03:28 PM
Skolon

8 
1,516 
On wikipedia it says that the pressure coefficient can be written as
C_p = 1  (V/V_{inf})^2
where V is the...

Sep2609 03:23 PM
naggy

1 
603 
Hello all,
Still at my frisbee modeling program, I started to ask myself how I could get better approximations of...

Sep2609 08:29 AM
thrillhouse86

3 
4,238 
I have a field ,B, I need to find the other field,A, such that
> __ >
B = \/ x A
I need numerical...

Sep2509 04:44 PM
ZapperZ

3 
1,151 
How does the viscosity of a fluid in a circular can affect the way the can rolls?
For example, 2 cans of similar...

Sep2509 11:58 AM
jambaugh

6 
2,681 
Hey, I was wondering
If I have a motor that can supply 6.156 kgf cm of torque operating at 20 rpm, how much weight...

Sep2409 05:06 PM
Bob S

1 
2,506 
Saw this on a test question today, it asked if you had 1 mole of reactant (don't know what kind of reactant...

Sep2409 04:48 PM
shredder666

2 
2,866 
please do explain in detail.

Sep2409 04:28 PM
sphyics

8 
7,506 
I've just seen induced electric field concepts. Could anyone provide a link, which explains it?
I had some rather...

Sep2409 04:19 PM
Bob S

1 
2,090 
Hey,
I'm not very good in physics but i have something which seems like a basic question only i could not find the...

Sep2409 10:59 AM
tinytim

1 
1,496 
Hi! I would appreciate your thoughts on something. :smile:
Let's say you have a ring with radius R rotating with...

Sep2409 10:32 AM
sophiecentaur

3 
837 
Hi,
Say I have a sphere of radius r that has a constant surface temperature of T_s.
The sphere is surrounded by...

Sep2309 08:50 AM
Mapes

5 
2,106 
Heat transfer is something I've been interested in since studying thermodynamics last semester, although during the...

Sep2309 07:07 AM
kateman

4 
3,608 
I understand that to find moment of force, we look at direction of force and perpendicular distance. In the diagram, O...

Sep2309 04:52 AM
Doc Al

1 
2,727 
This inquiry is in relation to internal combustion engines. I am trying to figure out how to maximize the mass of air...

Sep2309 03:29 AM
xxChrisxx

3 
1,309 
I was going through my textbook, Introduction to Electrodynamics, and I came across this question that puzzled me. ...

Sep2309 01:47 AM
tinytim

4 
860 
Hi,
Was doing some testing for work, but a lot of my physics are gone! Hope someone can help...
Here goes:
A...

Sep2309 12:46 AM
rustyphysics

12 
10,081 
http://www.physicsforums.com/attachment.php?attachmentid=20643&stc=1&d=1253537605
Look carefully. Of course, the...

Sep2209 11:37 AM
kyiydnlm

1 
703 
Reading Jackson this morning, where it was stated that the Lorentz force equations:
\frac{dU^\alpha}{d\tau} =...

Sep2209 10:43 AM
Peeter

6 
950 
I recently found out how to calculate the potential energy of a charged insulated sphere of radius R and charge...

Sep2209 05:19 AM
simpleton

13 
2,178 
what is the theory behind ....if close integral of a expression is zero..then the expression is itself zero

Sep2209 01:24 AM
Born2bwire

1 
956 
A car with mass M1,with a box upon it of mass M2 moves with constant speed v.(there is no friction).If the box is...

Sep2109 08:54 PM
sophiecentaur

1 
715 
why solid angle is A/r^2 ....why is this r^2....has it any similarity with s=rtheta??plz help me

Sep2109 07:45 PM
clem

3 
1,128 
A house with AC in a hot climate should be painted white (or covered with mirrors) to reduce absorption of light from...

Sep2109 06:09 PM
ejensen6

10 
2,869 
Hello,
I am stuck on the coriolis force. If an object is dropped how do I get the eastward deflection when looking...

Sep2109 04:41 PM
Cleonis

2 
1,599 
What does it mean to say that the fundamental relation of thermodynamics is homogeneous firstorder?
I struggle...

Sep2109 03:10 PM
Count Iblis

5 
2,129 
I tried to use Lagrangian and Hamiltonian to solve 1D elastic collision, but I got nothing but constant velocity...

Sep2109 12:18 PM
kof9595995

6 
2,329 
Hello,
I wonder if there is a common origin to the 'virial theorem' by Clausius and the 'virial expansion' or...

Sep2109 06:42 AM
DaTario

1 
780 
For some reason I have been extremely curious of how Newton derived his mathematical law for gravitation. You know
...

Sep2009 08:55 PM
alxm

1 
2,999 
Why is it that the equation for work done to stretch a spring is
W = 1/2k(x22x12)
while the work done by a...

Sep2009 08:26 PM
woodie37

11 
13,179 
Say i have a capacitor and i supply it with a voltage V and after that it has charge density sigmainitial on each...

Sep2009 07:17 PM
sophiecentaur

3 
740 
Imagine two small metal spheres of equal mass and size moving at the same speed in opposite direction collide with...

Sep2009 12:31 PM
mahela007

3 
1,983 
I am having a lot of trouble conceptually understanding this issue in Lagrangian mechanics:
I have an airfoil which...

Sep2009 02:37 AM
thrillhouse86

0 
911 
In this problem we assume that the photon mass is m > 0. We take a conducting sphere of radius R and put a charge of...

Sep1909 09:58 PM
Count Iblis

17 
3,657 