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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,892 
In ch 307 of the Lectures, Feynman explains that the field of a plane of oscillating charges at a point P is...

Nov812 07:46 AM
Sonderval

0 
648 
I am having trouble pinning down why the relative permeability of a transformer core will not directly affect the...

Nov812 03:22 AM
rutman

2 
893 
Hi
I've built a NST 15kV tesla coil and I hooked it up today and it kinda didn't work. I'm wondering if anyone...

Nov812 01:07 AM
K^2

4 
947 
In a PVT system, knowing the function U(S,V) (or S(U,V) ) allows us to know all the information about the system, so...

Nov712 11:31 PM
Rap

14 
1,807 
Consider the classic image problem with a conducting plane and a point charge. After finding out the charge density on...

Nov712 04:03 PM
Meir Achuz

3 
1,512 
Using a 30kg cubic block Ice at 20degC, I want to cool down a piece of steel which is resting on the seabed. The mass...

Nov712 03:47 PM
sophiecentaur

2 
695 
Hi, studying for exam and checking if i am doing this question correctly ,
Q: Cylinder radius R=1m length L=2m...

Nov712 08:19 AM
andrien

2 
674 
Here's an interesting puzzle:
The whole scenario takes place in one dimension of space.
Ball B is at rest. Ball...

Nov712 08:09 AM
A.T.

3 
798 
When the electromagnetic wave propagates in air and it meets the object with the size less than the wavelength then...

Nov712 07:32 AM
Andy Resnick

9 
910 
If I have a wave that looks pretty much sinusoidal but the peak positive amplitide is greater than the peak negative...

Nov712 07:28 AM
Philip Wood

2 
753 
Hello everybody!
There is interest in making pointlike light sources, especially to measure the quality of optics,...

Nov712 06:33 AM
Enthalpy

5 
583 
Hi all
I'm doing a project for energy efficient buildings with thermal insulation.(Just a leisure project and im...

Nov712 06:05 AM
sriram123

4 
1,202 
I am going to create a model, with two heatsources closely spaced (Cables with a current) Covered with dirt and at a...

Nov712 03:34 AM
nicklasaau

1 
632 
It is ussually thought that if you receive a shock touching only one cable is because you are not well isolated from...

Nov712 03:25 AM
rcgldr

5 
7,645 
For every force exerted by object A on object B, an equal and opposing force is exerted by object B on object A.
I...

Nov712 02:56 AM
Fredrik

4 
1,635 
The equation
v22 = vo2 + 2aΔy
is used to determine the change in position, acceleration, or velocity of a...

Nov712 12:46 AM
Simon Bridge

4 
1,035 
Hello, I am working on a project regarding truss analysis on a plane and I need to find all the forces acting on the...

Nov612 02:52 PM
A.T.

4 
1,028 
Imagine two cylinders in which one cylinder in within another.(Please refer attachment)
The annular space between...

Nov612 10:21 AM
nasu

2 
942 
I have a lot of confusion and I hope someone can help me in clearing my doubts.
considering a right cylindrical...

Nov612 08:53 AM
A.T.

1 
888 
Hello All,
I have some basic damping related questions that I am hoping you all can shed some light on or suggest...

Nov612 03:44 AM
K^2

5 
910 
Hi,
A parallel plate capacitor is charged from fixed voltage, after I cut voltage source.
Now, what's happened if...

Nov612 01:32 AM
Gh778

44 
2,528 
Imagine an electric field created by a electricity running through a looped wire. Leaving all other variables exactly...

Nov512 07:44 PM
Bobbywhy

1 
689 
is it possible to harness the lightening to get electricity.

Nov512 07:41 PM
Bobbywhy

5 
695 
I was wondering if anyone had any insights on how to estimate or discern the potential drops across a capacitor...

Nov512 12:02 PM
Sancor

1 
527 
An N45 Grade Neodymium Rare Earth magnet has a remnance (Br) of 1320 mT and Coercive force (Hcj) of 923 kA/m.
I am...

Nov512 11:32 AM
nasu

2 
942 
i have read an example on electrostatics that if anyone rub a rubber comb and wool , the rubber comb acquires the...

Nov512 09:15 AM
Meir Achuz

1 
696 
1. An object of unit mass moving with unit speed applies unit force to any object when the two collide. True or False?...

Nov512 08:32 AM
Chestermiller

23 
1,592 
Somebody slept through their lecture on resonance.
I don't know how to link video.
...

Nov512 03:03 AM
A.T.

1 
649 
Hi I'm trying to balance any 3d system with various fixed weights by selecting the correct lift forces for points of...

Nov412 06:39 PM
LordSimpson

4 
731 
if see a candle light you find the flame moving up.heat moves by conduction, convection
ans radiation. a teapot with...

Nov412 02:38 PM
russ_watters

4 
1,160 
1. Can you tell me the name of two particles having zero force of gravitation between them ?

Nov412 01:49 PM
mrspeedybob

2 
722 
Hi, I'm new to this forum.
So I do not understand how, in an inelastic system, momentum is conserved.
Consider...

Nov412 01:45 PM
rcgldr

18 
2,451 
Hi.
Imagine an imaginary car with a huge windmill on top connected to its enginator. Assume windmills and enginator...

Nov412 01:42 PM
A.T.

13 
1,019 
I am reading the book of Neuenschwander about Noether's Theorem. He explains the EulerLagrange equations by starting...

Nov412 10:44 AM
vanhees71

1 
673 
Ok,so John Taylor's Classical Mechanics has this small subtopic "energy interactions between 2 particles".And,in...

Nov412 09:19 AM
bp_psy

1 
741 
Hi.
Can you clarify for me the equation for gforce below:
F= ma + mg
I got this equation...

Nov412 07:22 AM
AJ Bentley

2 
1,301 
Hi.
I just wanted to know is there any limit to the amount of heat energy that a body can store in itself? For...

Nov412 04:43 AM
AJ Bentley

6 
833 
I believe this is pretty standard.
Given a mass m on a spring with spring constant k, a solution to the second...

Nov312 11:45 PM
Hetware

25 
2,494 
In my experience, a heavier sled rider always goes faster than a lighter one (given the same sled design). When...

Nov312 06:54 PM
Jespermj

15 
1,914 
Hi there. I'm trying to consider a system in which you have an electric field applied by a capacitor over two media,...

Nov312 05:54 PM
DrZoidberg

2 
607 