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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,678 
Assume you have a sinusoidal 500THz function generator and assume you have a compatible antenna. If you feed the...

Aug1812 12:32 AM
curiousatlarg

17 
1,406 
I know there is a difference between heat and temperature as once I was told what it is. I remember it being very...

Aug1712 11:28 PM
haruspex

7 
1,272 
Asking in most general shape, why do signals from upper Ghz and above don't seem to travel in wires?
Radio...

Aug1712 10:43 PM
curiousatlarg

25 
1,665 
Hey guys and gals, this isn't actually an assignment of any sort, so I didn't want to put it in the homework section....

Aug1712 07:10 PM
JackDP

11 
942 
Hi,
my question regards the application of the fluctuationdissipation theorem (Kubo  1966 Rep. Prog. Phys. 29...

Aug1712 05:47 PM
paloureiro

0 
478 
You are at the center of a sphere, and there is no net gravitational force on you. Which of the following do you most...

Aug1712 05:44 PM
Andrew Mason

17 
954 
Hi,
I am trying to figure out how to calculate the permeability constant of a lot of plastics by making solenoid...

Aug1712 04:50 PM
berkeman

16 
1,898 
Can someone explain what exactly happens when a capacitor is charged?
At the positive plate, are loosely bound...

Aug1712 10:14 AM
mfb

1 
502 
Suppose I have say a 40' long 3/4" garden hose stretched out linearly on a level surface. One end is attached to a...

Aug1612 06:49 PM
Studiot

7 
928 
Hello,
I am going through Whittaker's treatise on Classical Mechanics. In chapter 3 he derives the equation of...

Aug1612 05:28 PM
Muphrid

13 
898 
I am at the moment trying to do something different in the classical mathematical derivations of the equations for...

Aug1612 04:29 PM
gabbagabbahey

9 
668 
1) Does anyone have a general idea of how to experimentally validate or falsify the Third Law of Thermodynamics...

Aug1612 03:40 PM
Darwin123

4 
951 
Is it possible to construct a portable ground using an positively charged electret?
I think it would be useful to a...

Aug1612 02:04 PM
kmarinas86

22 
1,720 
So I am studying about waveguides and I am going through all this mathematics and then I realized that I do not...

Aug1612 10:44 AM
marcusl

4 
772 
Hello! this is my first post here,hope it's the good part of the forum.
I have some questions and i would...

Aug1612 08:03 AM
Hassan2

1 
862 
Hi Physicsforums
I am relearning classical mechanics and having a tough time dealing with a certain line from...

Aug1612 02:17 AM
sempiris

0 
486 
Hi all! I have been goofing around with antennas and wi fi radio equipment. Now I have a million questions about...

Aug1512 11:11 PM
curiousatlarg

0 
469 
Example: A common problem in undergraduate electromagnetic classes is calculating the electric field inside a solid...

Aug1512 07:26 PM
Only a Mirage

9 
1,865 
Is shown like this in my book:
Consider a rotating body with an angular acceleration α. There must be a tangential...

Aug1512 03:27 PM
aaaa202

16 
1,668 
Right, so I was going over some old (basic) electromagnetism principles (to make sure it doesn't all fall out of my...

Aug1512 01:24 PM
Tipox

31 
3,684 
It is said that toroidal inductors/coils (see http://fa.tusofia.bg/te/Brandisky/images/toroidal_coil.jpg) that are...

Aug1512 11:40 AM
dove

1 
1,069 
When a car turns too fast, it skids away from the center and I don't understand how that's possible in terms of...

Aug1512 10:24 AM
harrylin

11 
1,071 
hello,
new here and confused about newton second Law.
given:
vertical mass damper system, position of the mass:...

Aug1512 10:00 AM
induing

6 
831 
Determine the reactions at B and D when b = 60mm ?
(Diagram is attached)
Since B and D are hinged we don't know...

Aug1412 11:23 PM
ashishsinghal

3 
1,217 
Anyone help with an answer?
I have 90litres of Compressed air @ 3000psi. Can anyone tell me the actual temperature...

Aug1412 08:09 PM
cjl

1 
604 
Hi, new to the forums, nice to meet you folks, etc.
Today the English wikipedia featured a picture of Tracy...

Aug1412 01:01 PM
sanjib ghosh

2 
595 
Langevin equation describes the brown motion. But I don't understand the nose term η(t) in the equation. What's the...

Aug1412 10:49 AM
vanhees71

1 
766 
I'm looking at this picture from part of an explanation of the torque on a coil of current arranged as a solenoid:...

Aug1412 10:40 AM
Philip Wood

2 
818 
Im sorry to ask such a question but Ive been trying to understand the molecular reasons for why specific heat is high...

Aug1412 06:17 AM
Simon Bridge

5 
2,581 
Hey guys, I am looking for a textbook that I can cite as a source for a project, for which I am doing the math on.
...

Aug1412 05:51 AM
Simon Bridge

5 
1,102 
In uniform circular motion we need velocity and centripetal acceleration.
so if a object is placed in space around...

Aug1412 02:52 AM
RohitRmB

17 
1,228 
Sometimes I wonder if it actually possible to prove the actionreaction principle. I do know that Newtons laws are...

Aug1312 07:29 PM
atyy

4 
1,167 
Ill start with the third law of thermodynamics which denies the existence of zero kelvin (as stated by my lecturer)....

Aug1312 03:20 PM
Darwin123

26 
1,815 
Is there a formula for this? if object is 300m deep, 30m in diameter, 50,000kg, in a ball shape how long will it take...

Aug1312 11:03 AM
xodin

36 
1,990 
I want to know if the flow of electron act like a domino effect where 1 electron enter 1 atom than 1 extra electron of...

Aug1312 05:59 AM
BruceW

4 
665 
Why is Heat not normally trapped when compressing Air, and reused again in the expansion process of the same air?

Aug1212 10:39 PM
shavendome

2 
482 
Hi all,
I had a thought earlier about magnetic forces.
If there's a magnet attached (at rest) to my fridge, then...

Aug1212 08:40 PM
russ_watters

2 
574 
There is statements that pulsed microwaves could cause
buzzing and clicking sensations in the head.Even words
could...

Aug1212 05:33 PM
Stanley514

0 
587 
For a charged metal sphere of charge "+q" is the following statement true ?
all the excess charge is in static...

Aug1212 04:37 PM
tinytim

3 
921 
I don't quite grasp this statement :
Open attachment to view the image of whats going on
The field from a...

Aug1212 04:12 PM
mikeph

1 
377 