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

Apr2211 05:26 AM
ZapperZ

1 
47,900 
Hi, so I have a question where it asks me to find the distance between t = 0 and t = 60 for the equation v = 1/6(t(60...

Sep712 10:58 AM
MegaDeth

2 
536 
Why the electric field is in fact curved in that configuration? I'm just a little bit confused because normally if the...

Sep912 05:12 AM
Seydlitz

2 
860 
So I'm pretty sure the following paragraph is all true. Do the citizens of PhysicsForums agree? Please confirm and/or...

Sep1212 03:40 AM
vanhees71

2 
2,181 
In this document, how do I get 3.2 on page 12? I assume it is the EulerLagrange equation given in 3.1 just rewritten....

Sep312 08:41 AM
dextercioby

2 
826 
We all know that M.I of a Uniform rigid rod about an axis perpendicular to it's length and passing through it's center...

Sep512 02:43 PM
Nessdude14

2 
1,284 
If I have a wide beam, parallel to the x axis, with its COM at the origin, then I want it to curve about the y axis,...

Sep512 03:28 AM
Studiot

2 
845 
If I am trying to minimize triboelectric charging. What two substances when rubbed together would produce minimal...

Aug3012 05:37 PM
DrZoidberg

2 
991 
I understand the ideal gas law equation and the use of the gamma and it's relationships.
But what happens when a...

Sep1912 08:01 AM
jelanier

2 
738 
How can wave optics explain total internal reflection?

Aug2412 10:52 AM
Claude Bile

2 
1,004 
the charge(say positive) in figure induces negative charge on the disc and positive on sphere, the net force on charge...

Aug2212 04:12 AM
sazmat

2 
577 
Hi everyone, I have a very simple and classic question here.
Suppose I have a 10cm,0.01kg ruler (uniform density)...

Aug2412 06:00 AM
andrien

2 
963 
When i think of electromagnetic waves i think of a fast moving sphere of expanding or contracting fields,either...

Aug2412 05:09 PM
Drakkith

2 
688 
Textbooks on statistical mechanics usually discuss ergodicity only by words, without presenting any quantitative...

Aug2412 04:21 AM
Demystifier

2 
529 
Hi,
In a demonstration that was shown in class, two paper cups were dropped from different heights. The first was...

Aug2412 12:44 AM
Emilyjoint

2 
717 
Hi,
As I understand, the distance covered by an object in free fall is described as d = \frac{1}{2}gt2 or d = 5t2...

Aug2412 03:08 AM
willem2

2 
933 
I have been out of school a long time, so please go easy on me. If the answer is an equation with symbols or letters,...

Aug2712 09:28 AM
cowpup

2 
1,005 
I need a review of solenoid equations, such as equations for bar solenoids, toroidal solenoids, and toroidal solenoids...

Aug3012 11:09 AM
Prince Rilian

2 
972 
Hi all!
I'm trying to study the Poincare group and I have one problem. I'm reading a book: Gross D. Lectures on...

Aug2812 12:43 AM
vanhees71

2 
929 
Say an object is dropped out of a plane at height h above the ground and flying at a constant speed v0...
Ignoring...

Aug2812 09:10 AM
mfb

2 
705 
Suppose I have two charged particles with charge densities ρ1(r,t) and ρ2 (r,t) with corresponding velocity fields...

Sep1012 09:34 AM
Ken G

2 
829 
Hi,
I'm Chaitanya, 4th year undergraduate student in biomedical engg.
I have an idea of making a mobile phone...

Aug2712 01:04 PM
Kaycee92

2 
643 
Suppose you push a stick by a distance of s like on the picture. It will start to rotate as you along. My question is:...

Aug2712 02:37 PM
aaaa202

2 
638 
I want to calculate the force generated (as a result of expanding air) from pressure created by heating air up to a...

Sep1612 06:38 AM
CognitiveNet

2 
1,589 
I was looking through a Taylor's Classical Mechanics chapter and I have a question about the derivation.
So...

Sep1212 01:48 PM
opprobe

2 
871 
I have seen a lot of different formulas about the forces acting on a wheel. So now I don't know what to use.
So, I...

Sep1412 06:15 AM
mikeph

2 
891 
Hi Guys,
I have been asked to find out at what point a measurement device go out of calibration when dropped and...

Sep1412 01:48 PM
russ_watters

2 
1,596 
I believe I might have a fundamental misconception about work. Please correct me where my reasoning is wrong so I can...

Sep1512 07:13 AM
Andrew Mason

2 
840 
Hi,
Got a problem with the following derivation:
Coming from the Helmholtz equation one gets:
...

Sep1712 04:26 AM
OneMoreName

2 
1,342 
Hello,
I am studying wave mechanics and I managed to derive the linear wave equation with a string. Now I don't...

Sep1612 02:07 PM
sukretep

2 
536 
Situation:
A uniform cylinder (Mass M, Radius R) is rotating down a slope of incline θ and distance s, there are...

Sep1612 08:44 PM
Simon Bridge

2 
828 
Can someone please explain in a detailed manner about skin effect in electromagnetism, particularly wanted to know why...

Sep2012 03:10 AM
Blogical

2 
758 
Reading about solar panels i came across a peculiar description  "When the panel is short circuited, there is current...

Sep1912 06:08 PM
curiouschris

2 
2,010 
hello guys,
i need your help to clear my concept on total internal reflection ....when incident ray angle is...

Sep1912 06:37 AM
nasu

2 
1,035 
Temperature conversion:
273 + degree Celsius = Kelvin
Actually why is that 273? How does one come up with this?...

Sep1912 08:10 AM
Ken G

2 
764 
I was wondering if someone could explain how the laws of thermodynamics apply to these so called hydrogen on demand...

Sep2512 04:23 PM
october

2 
751 
I saw a baseball pitching machine that throws baseballs at 4070mph with one wheel... All that wheel does is rotate...

Sep2112 09:39 AM
ashishsinghal

2 
829 
Ok so I'm taking the SAT physics Test soon and i'm woefully unprepared!
I've taken physics 2 times already, honors...

Sep2612 11:04 AM
SanfordA

2 
912 
Hey guys,
So today I was in my Physics lab and a small argument arose. We had a pretest with a question that...

Sep2412 12:50 PM
Studiot

2 
954 
Beginning at 31:03 Dr. Susskind presents an intuitively very satisfying derivation of the EulerLa Grange equation(s)....

Sep2712 02:50 AM
vanhees71

2 
971 
(r×∇).(r×∇)=r.∇×(r×∇)
now in index notation it is written as,
=xi∂jxi∂jxi∂jxj∂i
but when I tried to...

Sep2812 01:03 AM
andrien

2 
636 