All Questions
Tagged with electromagnetic-radiation conductors
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Confusion regarding phase
As far as I know about phase if the phase difference between two waves is positive, the former is leading..and the latter is lagging. Then why has D J Grifith stated this?
If the phase of the magnetic ...
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1
answer
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Why is the Poynting flux not conserved across the interface between two conducting materials?
This question is part of my attempt to use an answer to another question I've posted on this site.
If I have two materials with complex indices of refraction, $\widetilde{n}_0$ and $\widetilde{n}_1$, ...
- 123
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Confusion about EM waves in a conductor, AC in wires, and skin effect
I am trying to get my head around these different points:
From Maxwell's equations we find that an electromagnetic wave in a conductor decays in amplitude with a characteristic length of about 1 cm in ...
- 197
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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 ...
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How are neutral conductors neutral even though they microscopically aren't?
When dealing with electromagnetic waves inside conductors we take $$\nabla \cdot E = 0$$
and I believe we use the fact that conductors are neutral to do this. However, even though conductors on ...
- 320
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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 ...
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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
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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}(...
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Does microwaves nevertheless pass through smaller slits?
It is known that the Foucault currents prevent the microwaves to leave a microwave oven (MWO). The waves can not pass tru several times smaller openings than their wavelength because the grid of the ...
- 651
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Why do we use wires/conductors to transport energy?
I am currently studying Maxwell equations and I learned that copper wires are essentially just wave guides for EM waves. Why do we not use an insulator to guide the wave and transport the energy which ...
- 225
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Turntables in Appliances and Standing Waves
I am just confused on a concept - maybe someone could correct me if I am wrong? I was just wondering why do some appliances contain a turntable.
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Is EM radiation released when metals, that have free electrons, are accelerated? [duplicate]
I have read that charged particles, when accelerated, emit Electromagnetic Radiation. This was the basis for rejection of the Rutherford's atomic model. But is this statement complete?
Metals have ...
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Reflection at a conducting surface Boundary Conditions: Not sure if I am understanding this correctly or not
In Griffiths Introduction to Electrodynamics (4th edition), when discussing the boundary conditions for a dielectric to (imperfect) conductor interface for a monochromatic plane wave, Griffith claims ...
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31
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8
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If air is a bad conductor, how does fire heat up a room?
If air is a bad heat conductor, how does fire heat up a room?
Could someone help me, as I really don't get this?
- 451
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What causes the phase difference between electric and magnetic fields of an EM wave in a conductor?
When an EM wave travels inside a conductor , we find that there is a phase difference between the Electric and magnetic fields within the conductor. The magnetic field lags behind the E field and ...
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