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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
45,388 
Hi,
I have attempted a basic gravitation question from “Classical Mechanics” R. Douglas Gregory (1st ed). I get the...

Jul2109 02:32 PM
Sourabh N

6 
2,019 
I would like to determine how long it would take a volume of water to cool from an initial temperature to a final...

Jul2109 04:58 PM
mgb_phys

4 
2,403 
Im trying to find the velocity for the surface wave on water. Its like when you throw a pebble on a small lake and...

Jul2109 05:35 PM
Hootenanny

1 
1,212 
How does one define an electric field??

Jul2209 05:43 AM
nooma

8 
1,000 
Hi.
Say a particle is moving around in uniform circular motion. The way my book attacks this problem is by placing...

Jul2209 07:29 AM
jmb

9 
2,118 
Hello,
I haven't learned a lot of physics and math, but I don't know how I misunderstand the following concepts:
...

Jul2209 11:17 AM
andytrust

3 
1,500 
Hi All,
I don't know whether this question makes any sense or not anyhow i will ask. For example, consider a...

Jul2209 02:47 PM
Amar.alchemy

7 
1,031 
can you help me relate velocity and angle in a graph? please, how are they related?
how is it possible to plot...

Jul2309 01:54 AM
Cyrus

1 
1,499 
i think
mirrors reflect light and light source 1 with x energy is reflected by the mirror which uses some of that...

Jul2309 02:31 AM
maverick_starstrider

16 
2,251 
One expression for angular momentum is L=2m*(dA/dt),where m is the mass of the body in concern and (dA/dt) is the...

Jul2309 06:10 AM
Urmi Roy

25 
2,321 
Someone on YoutTube stated...
Each magnetic pole drops off by 1/R^2. Once you get away from both poles (Cavendish...

Jul2309 10:28 AM
rockyshephear

18 
3,498 
Hello,
My first post! Thank you for any replies!
When looking at U values for windows (= 1/R) they are 99% of...

Jul2309 05:19 PM
Kavy

2 
932 
I have read that "any" function of new and old coordinates may be used to generate a canonical transformation....

Jul2309 06:07 PM
jojo12345

0 
620 
Hello,
I'm confused about the whole electromagnet thing. So far I've got these concepts:
 Passing a current through...

Jul2309 09:07 PM
Bob S

3 
742 
Hi All
Does anybody know if there is some formalism according to which we can describe the coulobian repulsion (or...

Jul2409 12:27 AM
dE_logics

11 
1,169 
I have a problem in regard to the doppler effect,which may be generalised to all wavessound,water etc.
Please...

Jul2409 03:36 AM
vin300

64 
4,148 
Would it be possible to determine the value of G by setting two very well know masses side by side on a very well...

Jul2409 10:18 AM
sganesh88

6 
792 
To which entitity (operators, wavefunctions etc) in quantum mechanics do the dynamical variables and the hamiltonian...

Jul2409 11:15 AM
guhan

3 
854 
I'm working on determining the differential equations governing two linked bars that rotate around a fixed pivot...

Jul2409 01:17 PM
berkeman

1 
2,174 
Hello
Say there's a uniform magnetic field changing in time (B=Asin(t) or something), and a ring (pic 1).
so...

Jul2409 01:43 PM
ibc

6 
1,430 
Alright I've been going crazy with this problem. I'm building an electrostatic loudspeaker. In order to get it right I...

Jul2409 02:32 PM
nasu

3 
1,020 
Hi
When reading about forces I see two things.
1. forces that act or do something.
2. force as something...

Jul2409 05:06 PM
russ_watters

6 
985 
the solution for current I, for series LCR circuit is
I = (E/Z)sin(wt+\phi)
Where Z = \sqrt{R^2 + (X_{L}X_{C})^{2}}...

Jul2409 05:30 PM
Bob S

3 
6,157 
Do you know which is the energy per mol required to ionize air? Once the air is ionized, does it recombine it´s...

Jul2509 01:26 AM
MATLABdude

3 
7,437 
In low freq magnetic communication, the carrier is not EM wave but low frequency varying magnetic field. Most of the...

Jul2509 02:09 PM
fleem

9 
5,726 
Hi,
The concept of "stationary / nonstationary EM fields" is not clear to me. Can someone please explain this to...

Jul2509 09:23 PM
Madara

0 
496 
I received this problem recently from a friend, and I think I have the right answer but I'm not sure. I also might not...

Jul2609 02:35 AM
diazona

5 
894 
This is a question from a mathematicallyinclined homeowner who knows he /should/ be able to figure it out, but can't....

Jul2609 02:43 AM
diazona

22 
6,266 
How does induction work?
Give me examples aswell.
Thanks

Jul2609 04:21 AM
Awsom Guy

2 
743 
After playing with an electrical socket (with caution), I realized there is 120v between the black and ground wires....

Jul2609 09:51 AM
turbo

2 
2,910 
Why do objects bounce? Let's say you throw a tennis ball at a wall. Why doesn't the ball just transfer its momentum to...

Jul2609 01:19 PM
vin300

8 
4,246 
Sources say if lines are parallel they will repel else try and merge which I don't agree and even see practically.
...

Jul2609 04:44 PM
larry moon

12 
2,827 
Since I'm around that old question about an observed phenomenon came to my mind:
 a cup is filled with water and...

Jul2609 06:15 PM
negitron

2 
2,979 
My roommate and I are working on a backyard physics/engineering project, with the intent to hopefully scale it up to...

Jul2609 10:19 PM
Moebius_Prime

5 
2,033 
I want to know the difference between the 2 types of rotations shown in the picture attached .
planetary orbiting...

Jul2709 03:50 AM
sganesh88

5 
1,029 
Hi,
Let us assume that I apply some amount of force at the end of the wrench to loosen a nut. This force makes...

Jul2709 01:33 PM
Amar.alchemy

4 
1,927 
Hi,
Can someone explain the concept of "Poincare sphere"? What's the relationship between the Poincare Sphere...

Jul2809 01:53 AM
Madara

2 
4,512 
On page 10 of Goldstein's classical mechanics, it was said:
"If V_{jj} were also a function of the difference of...

Jul2809 05:50 AM
sadness

2 
853 
I have been asking this question of everyone I meet and can't find a straight answer.
Imagine a wire rope anchored...

Jul2809 06:20 AM
jmb

5 
5,151 
This is a picture of me in my bath. (dont worry, it is purely diagramatic!). I face a wall to the front of the bath....

Jul2809 01:53 PM
negitron

1 
391 