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If you are seeking help with a...

Apr2211 05:27 AM
ZapperZ

2 
69,467 
The aim of this thread is to highlight recent (as in within the past 3 months) noteworthy physics papers that have...

May614 04:32 AM
Cthugha

168 
186,505 
How to prove that energy travels at group velocity and not phase velocity?

Jun1714 07:15 PM
UltrafastPED

1 
239 
Hi,
I was thinking of something: How are one supposed to calculate the moment needed for a scoop to scoop up a...

Mar314 11:51 AM
sophiecentaur

1 
240 
This is about wave reflection and transmission.
For an infinite string with a density change at x=0, consider an...

Apr2214 10:06 AM
UltrafastPED

1 
240 
So I can't find this anywhere, but I would really like an answer as it's driving me up a wall; Are the amplitudes of...

Jun1614 12:34 AM
Drakkith

6 
240 
How many reflections will be made by a light entering a 2m long optical fibre cable. If the angle of incidence with...

May614 04:40 AM
Rahulr2k

2 
241 
We are constructing a dip coater in our laboratory. But because of the disparity between the lowest and highest speed...

Jan2414 06:28 AM
Drakkith

1 
241 
Hi. I am trying to understand the multiplicity function Ω!/L!(ΩL)! where Ω= number of boxes and L= number of...

Apr814 03:54 PM
leeone

2 
241 
Say for example you have take a sample of 500ml from a bulk saline solution (NaCl and H20). If you know that for every...

May3014 09:42 PM
Nathanael

1 
242 
So I play the guitar, and I cannot use the same amp I use to gig with, because in my home basement, it's too sharp and...

Y 03:24 PM
enorbet

10 
242 
An environmentalist friend of mine wants to cool a building on his property (something like a shed or workshop) not...

Jul3012 12:19 PM
Sultan of Hel

0 
243 
Hi, all there is question with its solution in the picture which I understand but wanted to approach
in a different...

May1914 04:49 AM
mecheng

0 
243 
This may be intuitively obvious to you and I'm just missing it.
Say you had 3 balls each with a mass of 1g. Each...

May1014 06:54 AM
UltrafastPED

3 
244 
What's the difference between electric and magnetic fields, specifically I someone was to send a charged particle into...

Jun914 12:45 AM
Simon Bridge

2 
244 
It is given that:
1 kg of 0 degree celsius ice is put into a cup of 0 degree celsius cold water.
is the...

Jun1614 07:14 AM
DrClaude

8 
245 
I don't know how to integrate the MaxwellBoltzmann distribution without approximation or help from Maple.
Given...

Jun1014 07:05 AM
TeslaPow

2 
246 
Hi Everyone,
I am currently researching some corrosion pits that are growing in a spiral fashion.
Can anyone...

Apr914 05:27 AM
streeters

0 
247 
Hello everyone,
I'm studying the large plastic deformation theory based on the multiplicative decomposition of the...

Jun1714 03:17 AM
trabo

0 
247 
Hello everyone
I am reading a lot about Stimulated Brillouin and Raman scattering
I read the following difference...

Jan2314 07:50 AM
eahaidar

0 
248 
Hello,
Wikipedia states: Phase changes, such as melting or evaporation, are also isothermal processes.
I am...

Jun114 03:29 PM
Chestermiller

2 
248 
Hello ,
I have a rather odd question. I am trying to find a phenomenon that occurs in nozzles but am quite unable...

Feb1914 03:38 PM
ajd12

0 
249 
Hi everyone,
I'm new to transistors analyzing, and I need a way to correctly identify the voltages.
Let's take...

Jun1814 07:04 AM
phyzguy

8 
249 
do negative charges in electric fields of positive charges have negative electrostatic potential energy? am I write in...

Mar114 05:48 PM
dauto

1 
250 
Why is the focal point to the left of a concave lens called the second focal point? Isn't it just a matter of the...

Jun1214 06:27 AM
jtbell

2 
250 
So if an EM waves travels from one medium to the other, it refracts depending on Snell's law. But what happens when...

Apr314 12:24 AM
UltrafastPED

1 
251 
As we know there is no charge inside the conductor.(Consider the solid conductor......)
All the charge will...

Jun314 03:39 PM
nasu

1 
252 
Graduated College over thirty years ago. In physics, I recall a a question where one is required to weigh an object...

May1514 08:58 AM
NascentOxygen

1 
252 
Hi,
I was wondering if there was an equation for the flow rate through a straight vertical or angled capillary...

Jun414 11:33 AM
Andy Resnick

2 
252 
I've got a few things I want to make sure I have right about refrigerators. When the fridge operates, it removes heat...

Jun2314 10:55 PM
NascentOxygen

1 
252 
Say we have two separated observers which have a velocity relative to each other and are both looking at a system. By...

May1614 08:03 PM
mfb

1 
253 
Can someone maybe explain me(or has a good link to a page where this is explained)
why scattering in perpendicular...

May2014 10:09 AM
jennyjones

0 
253 
Hi all,
I am trying to understand about collision frequency that happened in ionosphere layer. In D region, below...

Jan2914 01:33 AM
s_hy

0 
254 
https://www.youtube.com/watch?v=f8S0PeOvHAA
I have a number of questions about the above video:
What are they...

Jun1514 10:25 PM
Simon Bridge

1 
254 
What is the highest efficient solar cells out there? I heard there was one that is 80% efficient. And there is a clear...

May1214 11:41 PM
Bobbywhy

1 
255 
Can anyone speak on the spectrum of sunlight reaching the upper atmosphere and the surface ? Specifically I interested...

Jun214 02:42 PM
UltrafastPED

4 
255 
Question :
The top of the atmosphere is at about 400 kV with respect to the surface of the Earth, corresponding to...

Jul2714 06:23 AM
NascentOxygen

1 
255 
Hi
Is the drag coefficient for a particular object the same in different mediums? Say we have Cd = 1 in air for one...

Jan2214 10:58 AM
cjl

3 
256 
Can someone please explain what the parallel axis theorem is?

May3014 06:33 PM
sophiecentaur

2 
257 
Angular momentum L is defined by summation of mrxv about a certain point. For a rigid body that rotate about an axis...

Jun1514 09:30 AM
mattt

4 
257 
An electromagnet pulls a ferromagnet from a distance(r), now there is a change in flux. The total magnetic field in...

Feb2414 12:39 AM
DashIQ

0 
258 
While using the potentiometer to measure the emf of an unknown battery the slider is adjusted so that the reading in...

Apr814 02:38 AM
Bobbywhy

1 
258 