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1 vote
0 answers
75 views

Non-vanishing bondary terms of the inhomogenous wave equation

I'm trying to follow a derivation of the solution to the inhomogeneous wave equation $$ \bigg[ \nabla^2 - \frac{1}{c^2} \frac{\partial^2}{\partial t^2} \bigg] \psi(\vec{r},t) = - f(\vec{r},t), $$ ...
Jerome's user avatar
  • 165
2 votes
0 answers
45 views

How to apply phasor transformation with multiple sinusoidal functions

I am seeing some questions in my textbook involving phasor transformation with multiple functions of cosine or sine in multiplication with each other but they didn't exactly showed how to do it and I ...
Tunguska's user avatar
  • 123
1 vote
1 answer
153 views

Variable separation method for solving wave equation

In variable separable method we assume the solution to be the product of such functions each of which is function of only one variable. What is the basis for that assumption? What allows us to assume ...
Sai Krishna Garlapati's user avatar
1 vote
2 answers
89 views

Find the time period ($T$) for an electric field wave: $E=E_0\sin{m t}\sin{2mt}$

Find the time period ($T$) for an electric field wave: $E=E_0\sin{m t}\sin{2mt}$ I thought $T$ is such that, $E(T+t) = E(t)$. As period of given sinusoidal function $E$ is 2$\pi$, $$ \Rightarrow 2\pi ...
vrintle's user avatar
  • 326
0 votes
0 answers
221 views

Deriving the wave equation

Given: $$\nabla \times \mathbf H = \frac{4\pi}{c} \mathbf j \ \ \ \ \ \ \ \ \ (1)$$ $$\nabla \times \mathbf E = -\frac{1}{c} \frac{\partial \mathbf H}{\partial t} \ \ \ (2)$$ $$\...
JD_PM's user avatar
  • 1,139
0 votes
0 answers
459 views

Deriving the wave equation out of $\nabla \times \vec H = \frac{4\pi}{c} \vec J$

I am trying to derive the wave equation presented by Alfven in his 1942 paper Based on the electrodynamic equations: $$\nabla \times H = \frac{4\pi}{c}J$$ $$\nabla \times E = -\frac{1}{c} ...
JD_PM's user avatar
  • 1,139
-1 votes
1 answer
282 views

Establish the dispersion relation ω = ω(k)

Stuck on this question, need help. Answer: w = ck
Mathematica's user avatar
1 vote
1 answer
60 views

Proof: Any function of the form $f \left(t - \mathbf{a}_n \cdot \dfrac{\mathbf{r}}{c} \right)$ is a solution to the $n$-dimensional wave equation

My electromagnetism (Maxwell's equations) textbook gives the following wave equation for free space: $$\nabla^2 \mathbf{h}(\mathbf{r}, t) - \dfrac{1}{c^2} \dfrac{\partial^2{\mathbf{h}(\mathbf{r}, t)}}...
The Pointer's user avatar
  • 4,322
3 votes
1 answer
336 views

Wave propagation with a complex coefficient $\beta$ in a Robin boundary condition. How does this affect scattering from the boundary?

Can anyone give me an idea of what happens in the following situation involving Robin boundary conditions with a complex coefficient. Lets say we have an incident electromagnetic plane wave $u(x) = e^...
csss's user avatar
  • 3,695
2 votes
1 answer
543 views

$u = 0$ is the only solution to the homogeneous Helmholtz equation $\Delta u + k^2 u = 0$?

We have that the solution to the inhomogeneous Helmholtz equation $$\Delta u + k^2 u = f$$ can be represented by $$u(x) = \int_{\mathbb{R}^3}G(x - y) f(y) dy$$ where $G$ is the fundamental ...
ManUtdBloke's user avatar
  • 2,614
0 votes
2 answers
36 views

Is the reach of the E- and B-field in an EM-wavefront infinite?

In my textbook, the wave-equation for EM waves was derived by using Maxwells' equations in integral form on a EM propgagation in $x$-direction (in vacuum), with E-field in $y$-direction and B-field in ...
Oyvach's user avatar
  • 129