All Questions
Tagged with electromagnetic-radiation conductors
10
questions with no upvoted or accepted answers
3
votes
0
answers
64
views
Can cell phones send message in the elevator?
From Gauss's theorem, a closed, hollow conductor shields its interior from fields due to charges outside, but does not shield its exterior from the fields due to charges placed inside it. So my ...
- 267
2
votes
0
answers
1k
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Is it a magnetic or an electric field that causes induction in the antenna?
wiki says that:
The electric field (E, green arrows) of the incoming wave pushes the
electrons in the rods back and forth, charging the ends alternately
positive (+) and negative (−).
but ...
user137879
1
vote
0
answers
46
views
What happens in a conductor when the electric field has a plasma frequency?
The complex index of refraction for a conductor is given by the equation: $$N(\omega)=n+ik=\sqrt{1- \frac{\omega_p^2}{\omega^2+i\gamma\omega}} $$ where $\omega_p^2=Nq_e/\epsilon_0m_e$ is the plasma ...
- 41
1
vote
1
answer
230
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Induced charge density on perfect conductor
Assuming there is a perfect conductor at $x=0$ in $\mathbb{R}^3$ and a plane EM wave $\vec{E}_i(\vec{x},t)=\vec{E_i^0}e^{i(kx-\omega t)}$ is coming from $x=- \infty$. We know, that the wave $\vec{E_r}(...
- 505
1
vote
0
answers
484
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Coaxial cable and faraday cage: why those shielding properties precisely?
The magnetic field produced by a coaxial cable outside of the outer shell is $0$. Indeed, integrating $\nabla \times \mathbf{B}=\mu_0 \mathbf{j}$ along a circle outside the outer shell, the inner ...
- 1,450
1
vote
1
answer
111
views
Conductors and non-optical photons
While there seems to be plenty of information available about the photoelectric effect and the emission and absorption of photons by conductors (metals) at optical frequencies, I’ve been searching for ...
- 11
0
votes
1
answer
66
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How to derive intrinsic impedance of parallel plate transmission line?
I've been Googling variations of this for hours but I can't seem to find any information on it and the formula my professor provided just seems to come out of nowhere and he provides no explanation or ...
- 2,327
0
votes
0
answers
22
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Effect of an electromagnetic field on an open metallic body
I have read on my book (I do not put its title since it is not in English) the following sentence about a metal body which receives an external electromagnetic wave (with Js we mean its current ...
- 1,319
0
votes
0
answers
140
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Do conductors reflect Wifi signals? If so why?
I know electric field can't pass through conductors, but I have seen people surround their wifi router by soda can (not entirely) for better signal strength. I want to know what really happens there.
0
votes
1
answer
61
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Wideband metamaterials in mobile-telecommunications bands
Were there any metamaterials (materials, settings, geometry) studied that are non-resonant (not frequency selective) in the frequencies between 700 MHz and 2700 MHz, therefore useful for mobile ...
- 183