# Questions tagged [maxwell-equations]

A set of four equations that define electrodynamics. They comprise the Gauss laws for the electric and magnetic fields, the Faraday law, and the Ampère law. Together, these equations uniquely determine the electric and magnetic fields of a physical system. DO NOT USE THIS TAG for the Maxwell-Boltzmann distribution, or the thermodynamical equations known as Maxwell's relations.

1,340 questions
Filter by
Sorted by
Tagged with
1 vote
40 views

### Deducing the Heaviside-Feynman formulae from Jefimenko's equations

I've tried to deduce the one point charge Heaviside–Feynman formula from the Jefimenko's equations. This should be possible, by replacing the densities with Dirac deltas, somehow, but I failed. Could ...
• 367
1 vote
28 views

### Intuition of Faraday's law at a boundary

I know that Faraday's law means that the tangential electric fields have to be equal at both sides of a boundary. I'm struggling to understand intuitively why this has to be the case. What would ...
• 11
30 views

### How do signals propagate down unballanced coaxial transmission lines?

I have previously asked a related question however it was closed, thus I have sorted out my thoughts into this revised question. This new question comes in two parts. I do not understand the concept ...
83 views

### Loop of wire in changing magnetic field, open circuit vs. short vs. intermediate

I've wondered about this for years. Assume you have a loop of wire in a time varying magnetic field. The loop has only one turn and you can either leave the ends disconnected (open circuit), short ...
• 348
40 views

### Energy density of a electromagnetic wave [duplicate]

The average energy density of a electromagnetic wave is given as $U_{average}$ =$\frac{e_0E^2}{2}$ My textbook also claims that "electromagnetic waves incident on a surface exert a force on the ...
• 103
38 views

### Coaxial Confusion, what really are unbalanced transmission lines? [closed]

Thanks for clicking on my question. I do not understand how an unbalanced transmission line works. Take for instance coaxial cable which is the subject of my confusion. This confusion arises from the ...
23 views

• 1
1 vote
52 views

### Maxwell Equations WITHOUT electric monopoles/charges

I was wondering if Maxwell equations in vacuum would also describe a universe without electric monopoles, but where dipoles etc. are allowed. \begin{align} \nabla \cdot \mathbf{E} &= 0 \quad &...
24 views

### Magnet falling in copper tube, radial force component

Consider a Dipole magnet falling through infinite copper pipe. If we displace a magnet a little bit so that the dipole isn't pointing to the same way as pipe (dipole isn't parallel to the pipe) we get ...
1 vote
50 views

### How is $E×B$ zero? [closed]

I was reading Feynman lectures vol. 2 pg no. 291. There I found the general solution of one dimensional planar waves along $x$ direction. My question is the when I apply dot product on $E$ and $B$ ...
40 views

### What is "free charge" in the macroscopic maxwell equations?

Wikipedia states the macroscopic Gauss' law as $\nabla \cdot \overrightarrow{D} = \rho_f$, where $\rho_f$ is the charge density of free charge carriers. I understand that conducting electrons in a ...
1 vote
82 views

• 11
54 views

### Superposition of two electromagnetic waves

If an electromagnetic wave in isolation with vector potential $A^1_{\alpha}$ satisfies the wave equation $\Box A^1_{\alpha}=0$, how do we construct the total electromagnetic wave that results from ...
• 181
1 vote
20 views

### Finding the geometry of induced electric fields using Faraday's law

Thinking of a long straight wire carrying increasing or decreasing current, we know by using Faraday's law of induction that the magnetic field produced by this wire will induce an electric field. Now,...
• 43
37 views

### Derivation of the maxwell equation in its differential form [duplicate]

I was going through the derivation of the differential form of maxwell equation and I ended up getting arrested at that part where it is used the gauss theorem to establish the follow relation The ...
42 views

### Satisfying and puzzling phenomenon about magnetic dipole

I just found a cool video of magnet falling through cooper pipe. So I naturally have a couple of questions about this physics phenomenon. I even tried to derive the equations of motion... During my ...