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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
45,577 
We know that the energy density of the electric field is:
\frac{1}{2}*\epsilon*E2
then, can we infer that the energy...

Jun309 09:56 PM
egust

34 
5,801 
Every book seems that it is a nobrainer that electric fields are zero in a conductor, but I do not understand this.
...

Jan2811 10:00 AM
Berko

6 
1,994 
On page 60 of his 3rd edition of Classical Electrodynamics, he discusses the method of images applied to a grounded...

Apr211 08:50 AM
Berko

6 
1,271 
Hello, everyone!
Any ideas how to measure drag or drag coefficient on a body of simple shape? We should conduct an...

Nov3011 11:39 AM
AlephZero

4 
4,174 
A large open tank, shown below, contains water at a height H. The water is allowed to flow out through a pipe whose...

Dec1411 05:39 AM
bermet

1 
1,950 
At parity of maximum resistance before failure (in the case of aluminum, deformation), weighs less aluminum or...

Aug913 10:01 PM
Aero51

4 
593 
Hi all, i have a doubt. How much teeth in relationship to his radius need to have a gear to be optimal? And, if i have...

Sep1813 09:57 AM
SteamKing

2 
348 
If newtons third law says there is an equal and opposite reaction how can there be energy transfer.
For example if I...

Apr3013 09:34 PM
SammyS

4 
1,364 
For example if I punch an object and it doesn't move, am I giving it energy, if so after doing that billions of times...

May113 05:16 PM
FireStorm000

3 
624 
We find in the literature the following relationships between electric field E and magnetic field B
B(z)=E(y)V/cc...

Jul1107 10:52 PM
bernhard.rothenstein

4 
23,223 
Consider please a conducting wire located in a plane electromagnetic wave propagating in the positive direction of the...

Jul1307 12:58 PM
bernhard.rothenstein

2 
1,649 
Defining the period measured by a moving observer relative to a stationary source as
T=t(n)t(n1) where t(n) and...

Aug3007 04:19 AM
bernhard.rothenstein

2 
3,245 
Consider please that an observer is located in a plane sinusoidal and polarized e.m. wave. He erects a metalic antenna...

Mar709 08:24 AM
clem

2 
960 
Consider the following statements:
1. If you move relative to me with velocity V I move relative to you with velocity...

Mar809 12:57 PM
bernhard.rothenstein

5 
911 
Many sources on basic gravity, like this quote from Wikipedia, say:
“In the case of a spherically symmetric mass...

Oct310 05:04 PM
Bernie G

16 
1,598 
This is problem from a text book whose solution I don't understand.
A small rock of mass 0.5kg is attached to a...

Jun1012 02:16 PM
BERNIE649

5 
1,498 
I have a basic question regarding black body cooling. Suppose a person at sea level on a clear night, were to use a...

Jul2007 08:33 PM
mgb_phys

8 
2,395 
Ok, so I have a 405nm laser pointer (bluish purple/uv). Had a few miscellaneous glass objects and was shining it...

Mar1114 02:37 PM
BernieM

15 
565 
Hi, I just need to ventilate and see your opinions.
Charge can be partitioned into groups of particles of one or...

Oct2613 04:29 PM
DaleSpam

11 
917 
Can we make a car or vehicle that can ride on the earths magnetic field here within the earths atmosphere?

Jun710 11:13 AM
bcrowell

1 
601 
Hi there!
I have a question, I am trying to find the critical point of a phase transition. For example in the Ising...

Nov1113 04:37 AM
Bersling

0 
327 
Suppose that we will proof the continuity of the first maxwell equation:
So we have div(\vec{E})=\frac{1}{\epsilon...

Nov307 09:46 AM
Bert

2 
2,345 
Where can I find online a good set of rigid body dynamics exercises? Thanks.

Jul1908 06:05 AM
Bert

2 
1,247 
This is a question which I have been been tossing around for some time. By looking at gravitationally induced...

Jan811 10:32 AM
hermitme

6 
5,169 
I'm designing a paddle wheel drive house boat and need to do some calculations to see if the parts I have on hand can...

Aug1909 03:32 PM
bertbcfm

0 
3,635 
I am attempting to design a base to support a post that will be pulled horizontally at its top.
A 2D image of the...

May312 05:12 PM
BertSmurf

7 
3,216 
Could someone show me the simple formula, showing how quickly
an item sinks in water.
Presumably the formula...

Jul1708 11:59 AM
bemortu

4 
3,054 
if i am finding the equipotential lines by using a conducting sheet, power supply, and muiltimeter to find the...

Sep2407 06:43 PM
Claude Bile

1 
3,551 
In 3D dynamics why is the angular momentum not aligned with angular velocity?
Does this mean H = Iw is wrong in 3D ?

Nov1405 02:11 PM
BobG

2 
2,353 
let us consider a charged body is connected with a massless spring. the system is connected with wall. Now the spring...

Nov1904 05:35 AM
besiktas_1

0 
928 
Hi Everyone;
I hope this is the right forum.
Here's the issue... with fixed pitch propeller aircraft, thrust is...

Nov1608 10:30 PM
bestpa

16 
2,169 
Hi
Can anyone tell me the differences between normal light (waves of the EM spectrum, i.e. visible light, gamma...

Feb906 05:57 PM
Claude Bile

5 
1,495 
Block 1 has a mass of 2kg and is moving to the right on a frictionless surface at 10m/s. Block 2 is ahead of Block 1,...

Jul1713 03:22 AM
tinytim

6 
748 
A ball is attached with a string on the side. When the string is pulled up, static friction accelerates the ball...

Aug1713 08:56 AM
bgq

7 
973 
The formula of friction force is
Ff = μN
can also be defined as
Ff = μ.m.g
One of my friend say that...

Jan2211 03:21 AM
Alvasin

4 
2,670 
I was reading Goldstein's Classical Mechanics vol.2 to brush up, and didn't get far before I got stuck. The book warns...

Aug1511 08:48 PM
clem

5 
1,915 
I feel like I am just plugging into equations when I solve physics problems and I dont know how to be creative in my...

Nov1108 06:36 AM
clem

8 
2,869 
i need help on a physics project that is due tuesday. the objective is to use a small solar collector to collect...

Jan1204 03:56 PM
pallidin

3 
1,616 
A few friends and I built a wave "machine." It's made by laying out brass "rods" about a foot long next to each other...

May2308 08:49 PM
bfr

3 
5,028 
I'm kind of confused about how tension works.
For example,
If I had two blocks that massed 5kg hanging on either...

Feb1009 02:15 PM
Archosaur

1 
711 