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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,837 
Electric field of an electromagnetic wave incident on a metal accelerates free electrons, and these accelerating...

Jan814 06:13 PM
sophiecentaur

28 
936 
For several years i have thought about air (fluid) resistance without getting deeper into the formulas that model its...

Jan814 05:14 PM
A.T.

1 
371 
on a soap bubble colours can be seen.my text book says its due to the interference betwewn light waves from the top...

Jan814 03:31 PM
sophiecentaur

2 
283 
Hi,
I have problem understanding some things about this particular LDV system(a Laser Dopler velocimeter).
...

Jan814 11:30 AM
Drakkith

1 
257 
Hi, so i have a fairly good understanding of most of the concepts relating to inertia. but my question is what is the...

Jan814 10:46 AM
CWatters

4 
409 
Hi all
First time poster, long time physics lover. ;)
My dad and I got into a discussion the other day since...

Jan814 04:11 AM
sophiecentaur

9 
5,161 
I have been reading Lagrangian from Classical Mechanics by John R. Taylor.
I have adoubt in a derivation which...

Jan814 03:21 AM
darwined

2 
317 
Hello.
I'm wondering about the Gaunt factor.
I'm currently interesting in the spectroscopy in which the Gaunt...

Jan714 07:17 PM
goodphy

0 
324 
Suppose the particle is at distance x from mean position and moving away . The standard formula for calculating...

Jan714 05:13 PM
sophiecentaur

29 
901 
This is driving me nuts. What am I missing?
Suppose you have an inclined plane with a mass m resting on it. The...

Jan614 06:42 PM
rexregisanimi

2 
334 
Hi, please could someone help clarify the reason why a mechanical wave is inverted at a boundary as I'm really stuck!...

Jan614 05:44 PM
sophiecentaur

3 
376 
the question is about the uniqueness theorem (right now I am reading in griffiths book).
the first uniqueness theorem...

Jan614 05:40 PM
Simon Bridge

10 
441 
Suppose that we have the potential V=\frac{exp(\lambda r)}{r} that \lambda is a constant. To calculate the charge...

Jan614 04:34 PM
maajdl

1 
245 
i know the relation between these two.
with increase in pressure, the viscosity of liquids (expect water] increases...

Jan614 01:55 PM
jagdishdash

2 
253 
Hey Dear forum,
I know I'm wrong, but I don't know why:
Since the Earth's descends 5 meters for every 8km, a...

Jan614 05:19 AM
sophiecentaur

11 
468 
Recently stumbled on this problem:
A uniform disk (I =½ MR2
) of mass 8.0 kg can rotate without
friction on a...

Jan614 12:18 AM
MariaResnick

2 
769 
I'm learning vectors. I read somewhere that if a vectors magnitude is constant, then its derivative is perpendicular....

Jan514 10:51 PM
Simon Bridge

11 
713 
How to calculate <n_i ^2> for an ideal gas by the grand partition function (<n_i> is the occupation number)? In other...

Jan514 05:10 PM
hokhani

2 
247 
Hi All,
Assume we have a package that we want it in an orbit with highest possible speed. In which orbit...

Jan514 01:42 PM
tfr000

2 
361 
Hey all,
I'm working on a project now where I am using a solenoid driven at a 10Hz AC current to create a magnetic...

Jan414 11:00 AM
Hassan2

20 
655 
I am currently working on a project that cools water moving through a chilled aluminum block. I am not familiar with...

Jan414 12:26 AM
onkarj

9 
32,502 
I'm working on an Apollo reentry program and would like to somehow check my results I got for reentry. I'm using 3...

Jan414 12:05 AM
roldy

2 
379 
This has botherd me for quite sometime ......imagine a beam or a simple scale supported at its centre and carrying...

Jan314 11:14 PM
kittu1421

2 
316 
HI gurus
I have found helped on this forum, that I am trying again.
I would like to know the steps I should...

Jan314 05:53 PM
Simon Bridge

14 
645 
Using this graph: http://postimg.org/image/vkv0ho8yb/
As the reaction proceeds it stops at the equilibrium as it...

Jan314 03:13 PM
Chestermiller

4 
406 
I'm figuring that this has been asked before, but I couldn't locate a previous thread.
Here's my problem:
A 1.0...

Jan314 02:20 PM
jldibble

3 
352 
Is it possible to have a zero vector? The question arises in the context of conservation of momentum. In center of...

Jan314 01:06 PM
BruceW

42 
1,373 
Self inductance of a coil : how does it happen ? I've got some hardtime trying to imagine how it happens , the phrase...

Jan314 01:06 PM
ElmorshedyDr

23 
701 
If I comb my hair with a rubber comb, the comb can be used to pick up small bits of paper on a desk. This says that...

Jan314 11:43 AM
Doc Al

8 
418 
In principle does classical physics allow us to make a fair Nsided die where N ≥ 3?
If I give you a set of N...

Jan314 11:22 AM
Hassan2

6 
421 
I came up with this problem, and solved for it, but I do question its accuracy, and id like to know how I could make...

Jan314 09:20 AM
Lonewolf723

2 
359 
Why are the reactions from two objects not at equilibrium ?

Jan314 09:00 AM
jtbell

4 
289 
Hi all,
Suppose we go in space where no gravity and friction exists. If there is a bar, in say  horizontal plane...

Jan314 07:34 AM
Tanya Sharma

10 
586 
If you have a rod oscillating back and forth by a frictionless pivot point near the end of one side of the rod and the...

Jan314 03:33 AM
256bits

1 
274 
Hi all,
I want to make sure I am understanding this correctly.
Say we have two identical particles orbiting (in...

Jan214 10:57 PM
kittu1421

2 
352 
Suppose a (parallel plate) capacitor of capacitance C is charged to a potential difference V and then disconnected and...

Jan214 10:42 PM
DaleSpam

10 
1,493 
Postulate a parcel of air that is transmitting sound waves. Can that parcel ever be considered to be in a state of...

Jan214 10:36 PM
Simon Bridge

9 
1,611 
I have doubts of how can I put my frame of reference in a simple harmonic motion vertical spring. Normally the books...

Jan214 08:09 PM
Simon Bridge

1 
245 
Assume 5 charged particles (charge 1) constrained to live on the surface of a sphere are in a configuration that...

Jan214 07:25 PM
Simon Bridge

3 
336 
I know Newton described it as 'the quantity of motion' but are there any other more descriptive or better definitions?...

Jan214 05:56 PM
Simon Bridge

5 
253 