All Questions
Tagged with frequency electromagnetism
80
questions
1
vote
1
answer
55
views
Why does the energy (and thus frequency) of a photon entering glass stay constant if some is used up to accelerate electrons and slow down the light?
I'm learning optics and have been told that when light enters a medium (e.g. glass) and slows down the frequency of the light stays constant while it is the wavelength which is reduced. The ...
- 531
0
votes
1
answer
100
views
Why doesn't the frequency of a cyclotron make an impact on the radius of the path of a charged particle?
The cyclotron frequency is given by $$f=\frac{qB}{2πm}$$
Obviously this equation has nothing to do with the radius.
But my question is, when the frequency increases, shouldn't the velocity increase, ...
- 107
1
vote
0
answers
78
views
How can I find if it is gold or lead with waves? [closed]
I would find if a bowl is made of lead or gold know freqencies $w_{1}$ and $w_{2}$ and a vibrator induces waves at $z=0$ (and there are reflected waves). I do it with progressive plane electromagnetic ...
- 47
1
vote
3
answers
171
views
How to Measure Energy of a Electromagnetic Wave accounting also for frequency?
We know a way of measuring energy of a electromagnetic wave is the Poynting vector, which is independent of the frequency. But let's say we want to make two different electromagnetic waves, with ...
0
votes
1
answer
66
views
How do you extrapolate frequency data from FDTD simulation time data?
Context: Im a PhD student who plans on doing research in theoretical plasmonics/nanophotonics, so I am studying up on understanding FDTD. I am having a bit of a conceptual issue regarding ...
- 1
1
vote
2
answers
104
views
Non-resonant source in a conducting cavity, what happens?
First of all I'm aware of this post but my question is a little different.
Say we have a perfectly conducting cavity with supported frequencies $\omega_n$ and a harmonically varying source within ...
- 1,780
1
vote
1
answer
77
views
Photon emission rate frequency dependency
I am puzzling over the dependence of the energy flux of electromagnetic radiation on the frequency of the source.
The power radiated in any direction or solid angle from a charged particle ...
- 1,030
0
votes
2
answers
88
views
What happens to those parts of the amplitude that are not inside the black hole? [closed]
Assuming that a sinusoidal wave with an amplitude a million times bigger than the diameter of a black hole enters a black hole, what happens to those parts of the amplitude that are not inside the ...
- 19
0
votes
1
answer
137
views
What is the highest frequency of alternating current?
What is the highest frequency of AC that we can possibly produce?
is there only one method of inducing AC?
for dipole antennas that can produce frequencies up to GHz, it must need an AC current, or is ...
- 156
0
votes
1
answer
120
views
Why are high frequency signals often described by power (dBm) and not voltage/current amplitude?
Let's consider a lock-in measurement of a resistive device. One may do a DC sweep with an added AC component to get a differential conductance measurement. The AC reference component for a typical low ...
- 3
1
vote
0
answers
23
views
Can cyclotron/gyromagnetic resonance occur if the peak of an AC wave corresponds with the resonance frequency?
So basically I'm curious if it's possible for cyclotron resonance to occur with a non-static, AC magnetic field if the frequency of it is equal to the cyclotron resonance frequency at the peak AC ...
- 383
0
votes
1
answer
55
views
Frequency response of ferrite filter
Why ferrite material only passes low frequency and blocks high frequency. I mean what's going inside this material which is leading to show such frequency characteristics?
1
vote
0
answers
31
views
Integrating Planck's relation
By Planck relation, we know that an energy of a single photon is $E = hf$.
If we are given EM-waves with interval of frequency $f_1$ to $f_2$, does integrating from
$\int_{f1}^{f2} Edf$ $=\int_{f1}^{...
- 275
-1
votes
2
answers
80
views
How can the given formula yield a frequency, when it doesn't have a parameter with time units? [closed]
This is the formula for plasma frequency.
$$w_{plasma} = \sqrt{\frac{4 \pi n e^2}{m} }$$
How can this formula yield a frequency, when it doesn't have a parameter with time units?
0
votes
1
answer
34
views
How and why does a nonlinear element produce the sum and difference of two radio frequencies?
For a resonant circuit the voltages of the capacitive and inductance reactance cancel and the currents of the capacitive and inductance reactance also cancel leading to a zero reactance. Is there a ...
