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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,936 
Hi all,
I'm a complete novice when it comes to describing images in frequency space and i understand that it is a...

Jun1213 11:20 AM
u0362565

4 
532 
Hello everybody! This is my first thread and I'm just kind of discovering the forum. If I should make a presentation...

Jun1213 10:42 AM
gerardpc

2 
1,234 
in waves and oscillations i read that any bounded medium oscillates in a particular freuency...why is it so?i need a...

Jun1213 10:12 AM
nasu

3 
490 
Reading in Russian sources I see they use ballistic coefficients such as these:
BC = 3.0 kg/m^2
or alternatively...

Jun1213 09:59 AM
Simon Bridge

1 
618 
I understand that too long of a time scale won't resolve an event clearly, and too much has the risk of exciting...

Jun1213 01:45 AM
Simon Bridge

5 
604 
What is the key reason?
I mean if you think about it, poles are just something we create to distinct the magnetic...

Jun1213 12:12 AM
Phztastic

2 
745 
I've read recently about systems with the ability to reach negative temperature: where entropy decreases as energy...

Jun1113 07:37 PM
Mute

6 
534 
Could I please have help with something: If I generated hydrogen via electrolysis from water, sent it high up a long...

Jun1113 05:46 PM
russ_watters

43 
2,681 
A typical evaporative cooler works by pumping water from a reservoir in the bottom on the cooler onto fiber pads. A...

Jun1113 05:44 PM
russ_watters

1 
460 
Given a general solution to the fixedend twomass coupled harmonic...

Jun1113 05:12 PM
Fnkcook

0 
405 
I get that they have to be at the same position relative to the earth
but why is it that they have to be...

Jun1113 04:31 PM
jbriggs444

5 
1,088 
I just learnt vectors as a prerequisite to learning mechanics and I have a few doubts:
1) For 1D motion, there are...

Jun1113 09:44 AM
rishch

17 
1,141 
What cases can the hall effect happen?
While reading this source. It states : "This is most evident in a thin flat...

Jun1113 06:48 AM
Simon Bridge

1 
513 
Does anyone out there know how I can calculate the magnetic dipole moment of a simple bar magnet?
Or any kind of...

Jun1113 03:50 AM
Jano L.

10 
1,965 
Hello all,
I am in need of understanding of magnetic fields. More specifically i was wondering exactly why there is...

Jun1013 07:44 PM
WannabeNewton

1 
524 
Hey forum
I need to ask for a link to a page for Variable density or preferably an explanation from someone who...

Jun1013 01:02 PM
bigfooted

2 
528 
Hi,
I'm trying to use image charges to find the force that apply on the following particle (on the attachment) ,...

Jun1013 05:25 AM
adamp121

2 
415 
I found the answer already. Please delete this post.
Thanks

Jun1013 04:00 AM
yungman

0 
454 
Hello folks,
I'm being tricked by the pesky friction force again.
I know that static friction acts just to put...

Jun913 11:16 PM
SteamKing

4 
595 
Hi,
I have a question regarding the boundary condition present for a dielectric immersed in a static field. I hope...

Jun913 06:59 PM
Apteronotus

2 
706 
I think I sort of know the answer but I'm still wondering how I can achieve what I want to achieve.
I basically...

Jun913 03:42 PM
russ_watters

2 
673 
Hello all,
I was wondering if the temperature of a plasma is relative to how much of it there is, or if it is...

Jun913 03:17 PM
bigfooted

1 
419 
Hi,
One of the boundary conditions when solving for the potential, \Phi, outside a dielectric sphere placed within...

Jun913 11:18 AM
Apteronotus

2 
541 
the calculation of the E field a distance z above a spherical surface of charge gives rise to this integral which can...

Jun913 10:05 AM
mathnerd15

10 
1,050 
Hi!
I am trying to understand the statistical mechanics derivation of the ideal gas law shown at:...

Jun913 09:07 AM
vanhees71

4 
976 
Given some body with a constant force F acting on it upwards
(The body is subject to the gravitational force due to...

Jun913 07:30 AM
Philip Wood

7 
625 
So heat capacity is the change in the mean value of the internal energy when the temperature is changed: C = d<E>/dt...

Jun913 07:25 AM
aaaa202

3 
711 
Hi,
I have read loads on LCD operation and in particular NTLCD and understand the twisting of the light by the LC....

Jun913 03:09 AM
berkeman

1 
557 
Hi there, sorry for asking a question as my first post instead of contributing to the community however I have a...

Jun813 04:21 PM
Aero_UoP

4 
1,346 
Are there any unanswered questions in classical mechanics?
By unanswered I mean unanswered and attempted. I could...

Jun813 06:10 AM
lightarrow

19 
2,600 
This is a problem that's appeared in a game I am writing, and is a bit beyond the mechanics I can sortof remember...

Jun813 05:24 AM
mfb

4 
584 
1) Is birefringence different in plastics, tempered glass and calcite crystal?
In plastics I see rainbow color...

Jun813 03:44 AM
llynne

5 
777 
hey all
so i am taking a class on thermal dynamics this summer and am using Kaminski's "Introduction to Thermal and...

Jun813 12:36 AM
joshmccraney

0 
451 
At the moment, I am reading the book Relativity, written by Albert Einstein regarding his special and general theory...

Jun713 05:00 PM
tinytim

4 
555 
Let's consider a stationary ball lying on the floor.
The weight of the ball acts downwards and the normal reaction...

Jun713 03:27 PM
Jadaav

5 
944 
Is additive color mixing a linear process (or close to)?
(if this question has already been answered in detail,...

Jun713 02:50 PM
Reactor89

0 
452 
The goal is to find a reasonable solution to the surface charge density that would cause constant current through a...

Jun713 01:57 PM
MisterX

0 
445 
I have a bit of a theoretical question. If one has a current carrying wire in a magnetic field such as in an electric...

Jun713 12:22 PM
sven1019

2 
483 
Hi,
I am wondering if it is possible to generate unpolarized light using the RF module in COMSOL (I have version...

Jun713 12:12 PM
mornna

0 
586 
Hi I had a quick question. From what I understand resonance is when a natural frequency of an object is matched by the...

Jun713 11:21 AM
Philip Wood

4 
1,068 