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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,678 
I have seen the derivation of the centripetal acceleration formula a=v^2/r by saying r= rcosθi+isinθj=rcosωti+rsinωtj...

Feb114 01:26 PM
GeneralOJB

3 
250 
I'm learning about Hooke's law and modulus of elasticity (also known as youngs modulus) but it seems I am being taught...

Feb114 09:30 AM
AlephZero

3 
248 
Greetings,
I am trying to to show that the force in this form:
...

Feb114 07:04 AM
Meir Achuz

2 
224 
Hello i wasn't sure if to ask this in here or in homework! I stumbled upon an assignment to build the model of photon...

Feb114 02:31 AM
Simon Bridge

1 
185 
Imagine an infinitely stretchable elastic band where one end is attached to a vertical wall and the other on a horse,...

Feb114 12:35 AM
orlan2r

3 
180 
How much does gravitational pull on an object decrease if the distance is increased 10 fold for example?
If planet...

Jan3114 09:43 PM
jedishrfu

1 
210 
How is the back induced current in the secondary coil transferred to the primary ? I know how mutual induction occurs...

Jan3114 05:14 PM
sophiecentaur

6 
359 
What is left if all matter and energy is removed from a particular region in space?
For example, say I completely...

Jan3114 03:16 PM
HallsofIvy

6 
210 
source:
http://rufacts.com/news/view/30934.html
I understand the source means to say Mujtarbay Otelbayev has found...

Jan3114 02:16 AM
gato_

2 
467 
:confused:

Jan3014 01:32 PM
CWatters

16 
593 
Hi all,
I was wondering if I am having a definition problem on mechanical work.
Since dW = PdV (as I was told in...

Jan3014 09:47 AM
Philip Wood

5 
331 
Hello,
I am having a conceptual difficulty understanding the following scenario
Suppose you has a tank with a...

Jan2914 10:58 PM
Chestermiller

1 
223 
Why is the position of an image the intersection of 2+ rays?

Jan2914 04:37 PM
sophiecentaur

4 
209 
Hi all!
Imagine you have an ideal sphere (made of steel or plastics). Then fill it completely with some fluid, e.g....

Jan2914 02:12 PM
mfb

1 
191 
Hello everyone,
Today, in class, I learned about the equipartition, and the degrees of freedom a thing can possess....

Jan2914 11:17 AM
sophiecentaur

5 
240 
Hello Everyone,
I understand that sometimes in physics we make a model of some physical system purely for...

Jan2914 06:09 AM
DrClaude

3 
187 
hey pf!
in reading a book on viscous stresses i found the following:...

Jan2914 12:02 AM
joshmccraney

9 
228 
Hi guys,
To celebrate my 29th post (I know!) I wanted to ask an extragood question, something I've been meaning to...

Jan2814 11:59 PM
Physicist50

4 
395 
I am studying surface tension and I am summing up what I have learnt through books till now:
→ On a molecular...

Jan2814 07:31 PM
Simon Bridge

3 
249 
Diffraction on 1D grating is covered in many physics books. Usually they cover simple case when incident light is...

Jan2814 11:57 AM
Lok

1 
184 
Consider the system shown in the picture.
http://updata.ir/images/m9wcnahubdfanhq9edok.jpg
What are its degrees of...

Jan2814 09:55 AM
Shyan

2 
223 
An array of N magnets which can turn freely about their centers in any direction in 3d space is distributed uniformly...

Jan2814 06:12 AM
intervoxel

4 
294 
Today in an engineering thermodynamics lecture, the professor gave an example of a gas doing work. We had a cylinder...

Jan2714 11:40 PM
Chestermiller

6 
295 
Hi guys,
The other day I found myself asking the question below and couldn't quite manage to realign my own...

Jan2714 08:39 PM
anandr

12 
283 
Are there any realistic scenarios for which center of mass is not almost exactly equivalent to the c.o.g., i.e. they...

Jan2714 12:07 PM
BruceW

8 
353 
The attached drawing represents 4 wires. The top and down are still. The right and left move with the same velocity v...

Jan2714 06:16 AM
Philip Wood

3 
220 
For example, I would like to visualize the transformation
u=cot1(1/α y/x)
v=αx2+y2/α

Jan2714 02:12 AM
bigfooted

3 
204 
Consider a monatomic gas of hydrogen (just to make the example as simple as possible) at a temperature T. If I use...

Jan2714 12:34 AM
Sonderval

9 
254 
hello guys
could anybody tell me the method of finding the range of a rocket launched from height h,
the rocket of...

Jan2614 07:16 PM
ChrisVer

2 
254 
Hello. When you flip a switch and pass a current through a solenoid, the changing magnetic field creates an electric...

Jan2614 04:54 PM
ArchieDave

0 
150 
Hi, I'm curious, how would I create an electric field to a noble gas in a sealed vacuum and how much energy is needed...

Jan2614 01:26 PM
jasonRF

4 
253 
This post specifically queries the absorption, by matter, of (thermal) radiation which has been emitted from a source...

Jan2614 01:19 PM
Arfur Bryant

39 
703 
I'm hoping to make (or model) these little cells on my own, but I'm not entirely sure how it can be done with...

Jan2614 08:18 AM
boneh3ad

3 
178 
My physics textbook is talking about blackbodies and has a graph showing Power radiated as a function or wavelength on...

Jan2614 08:02 AM
SteamKing

5 
246 
An electrocardigram measures the electrical current in the heart by using several "leads". These leads have +ve and...

Jan2614 04:16 AM
BobP

0 
180 
I've been trying to solve the following problem involving Angular Acceleration and the inertial tensor for about 2...

Jan2514 07:11 PM
ScanCrowRadio

0 
242 
Hi,
I found out this paper
http://www.pha.jhu.edu/~javalab/pendula/pendula.files/users/olegt/pendulum.pdf
with...

Jan2514 05:47 PM
DaleSpam

13 
290 
Hello, I am trying to understand a short literature article (doi: 10.1021/ja01635a030). I am not sure how much...

Jan2514 02:25 PM
blaisem

4 
230 
Hi,
I'm now endeavoring to calculate laser fluence using some laser parameters.
The required parameters to...

Jan2514 09:56 AM
UltrafastPED

5 
404 
I'm trying to generate a magnetic field that's strong enough to be detectable (i.e., still stronger from the earth's...

Jan2514 09:40 AM
UltrafastPED

4 
181 