All Questions
32
questions
7
votes
5
answers
14k
views
Light waves can't have a wavelength
The wave nature of light comes from Maxwell's equations. More precisely, the two wave equations that come from them:
$$\Delta\vec{E}=\mu\varepsilon \frac{\partial^2\vec{E}}{\partial t^2}\\
\Delta\vec{...
- 267
0
votes
2
answers
70
views
Why do parabolic antennas need to be the same width as their wavelength?
I am reading the wikipedia page for parabolic antennas, and have a question about the below quote:
In order to achieve narrow beamwidths, the parabolic reflector must be much larger than the ...
- 137
2
votes
1
answer
220
views
How do we know the wavelength and frequency of electromagnetic wave? [closed]
From my understanding, the frequency and wavelength of a mechanical wave can be observed by the motion of the particles (i.e., as the particles oscillate from their state of equilibrium, the wave ...
-1
votes
1
answer
67
views
The connection between kink and wavelength
As we know, in EM wave, with the oscilation charge (for simplicity, charge was moving at constant speed, then accelerated and then continued moving with constant speed again), kinks are produced. The ...
0
votes
1
answer
166
views
De Broglie wavelength of a photon
The de Broglie wavelength of a photon and the wavelength of its corresponding electromagnetic wave are numerically the same. Is this just a coincidence and the two waves are different or is the de ...
- 128
0
votes
1
answer
66
views
How to correctly understand wavelength of EM waves?
When we mention wavelength of EM waves, does the wavelength mean vacuum wavelength?
Is the frequency of every scalar component (x, y and z) $c/λ$, no matter whether it's linearly, elliptically or ...
- 69
-2
votes
1
answer
260
views
What is the wavelength of red light in vacuum?
According to Wikipedia,
It has a dominant wavelength of approximately 625–740 nanometres.
However, I'm not sure in which medium this wavelength was measured. Was this wavelength measured in a vacuum?...
- 1,018
0
votes
3
answers
474
views
What is the wavelength of light in a practical sense?
Okay, so I know that a wavelength is a distance of crest and a trough added together which makes a whole wave, but what is it in the real sense? Like in the case of sound I know when we say "...
0
votes
4
answers
156
views
Difference between wavelengths relation to frequency and period relation to frequency
I know that:
$\frac{1}{T} = f$
For some oscillation or sinusoidal wave. For instance, a period of 2 has a frequency of 1/2
And, in the physics I have taken the formula would be like the one given ...
- 1
6
votes
6
answers
2k
views
What ties high frequency electromagnetic waves to short wavelength and converse?
Why is it not possible to have waves with high frequency (high energy) and great wavelength and converse?
What physical quantity ties frequency to wavelength in an inversely proportional way?
- 71
0
votes
1
answer
155
views
What is minimum possible wavelength of electromagnetic waves? [duplicate]
Is it limited? Is the maximum possible wavelength limited?
- 768
3
votes
1
answer
1k
views
Why smaller wavelengths have higher penetrating power?
I've read that x-rays and gamma rays penetrate deeper whereas greater wavelengths like infrared don't go deep. Moreover, out of the two of radiations (alpha, beta) beta travels more in air on account ...
- 43
3
votes
1
answer
399
views
Can de Broglie Waves have frequency, just because we know de Broglie wavelength formula? [duplicate]
Sub-question if Yes: de Broglie wave is also often called the matter-wave. While we can find the frequency of an Electromagnetic Radiation from its wavelength $(c=\nu\lambda)$. $c$, in this case, is ...
- 753
3
votes
1
answer
2k
views
Does grounded sheet metal reflect or absorb radio waves?
By "radio waves" I mean waves used for radio transmission appliances, e. g. within 1 MHz to 10 GHz.
If the size of the metal sheet makes a difference, please answer for a infinite sheet and a fridge.
...
0
votes
2
answers
189
views
What is considered the frequency (and wavelength) of guided waves in a waveguide?
In a rectangular waveguide with sides of length $a$ and $b$, the dispersion relation is
$$\beta^2 =\omega^2\mu\epsilon=\beta_z^2+\beta_x^2+\beta_y^2=\beta_z^2+\beta_s^2.$$
So we have
$$\beta_z = \...
- 27