All Questions
Tagged with electromagnetic-radiation frequency
232
questions
11
votes
4
answers
2k
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Can the laser light, in principle, take any wavelength in the EM spectrum?
Can the laser light, in principle, take any wavelength in the EM spectrum? I don't think there is what prevent this in principle, right?
- 959
-1
votes
2
answers
80
views
What's the difference between the different kinds of EM waves?
I am an A-level student.
We have traditionally been taught that different types of EM waves exist only between certain ranges of wavelengths and frequencies.
However, I learned that electromagnetic ...
1
vote
1
answer
45
views
Why do we see objects with a given color?
I'm currently studying Electromagnetic Optics, and I don't quite understand the (classical) process through which we perceive an object with a given color. From my understanding, I'd make a ...
- 1,616
15
votes
6
answers
7k
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Why color depends on frequency and not on wavelength? [duplicate]
To explain my question lets consider this example:
The wavelength of light in a medium is $\lambda=\lambda_{0}/\mu$, where $\lambda_{0}$ is the wavelength in vacuum. A beam of red light ($\lambda_{0}=...
- 2,517
1
vote
3
answers
171
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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
0
answers
28
views
Frequency of EMR vs clockspeed of a processor
I was recently reading this thread on Reddit where people discussed the implications of a "Terahertz processor", a computer processor that operates at a clockspeed of greater than 1 ...
- 101
0
votes
1
answer
22
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How do i calculate change of momentum when I send a photon in the direction of travel
Say a spaceship is traveling at a certain velocity v (>>c) and it emits light from the nose of my spaceship in the direction of travel. The speed of light is finite and hence there should be a ...
- 383
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
1
vote
2
answers
64
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Under what conditions do waves stay monochromatic?
Based on my intuition, once light is monochromatic it will stay that way unless you actively try to change its frequency. My intuition stems from the intricate optical laser setups in my lab that ...
2
votes
2
answers
207
views
Does the formula $E = hf$ apply to all electromagnetic waves?
The formula $E=hf$ shows the energy contained in one photon. Here, we use the simple half wave dipole antenna to evaluate the energy of photons at different frequencies. Surprisingly that gives a ...
- 31
1
vote
1
answer
63
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If the speed of light is a constant value and the wavelength is constant (antenna), how can one antenna transit/receive different frequencies?
The speed of light is about 300,000,000 m/s, and the wavelength is determined by the design of the antenna, how can one antenna transmit different frequencies other than just the one defined by
f = c /...
- 13
2
votes
1
answer
220
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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
vote
0
answers
41
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Change of light from not visible to visible
Can light from infrared or UV change to visible light when it passes through some other material?
- 11
4
votes
2
answers
341
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Frequency of the photon in general relativity
There is an observer at ($r,\theta, \phi$) outside of the Schwarzschild blackhole. A beacon is falling into the black hole along $r$ coordinates of the metric and is emitting radiation. At $r_{em}$, ...
- 299
0
votes
1
answer
101
views
Is there laser operating at megahertz?
I have tried to find a laser with working frequency at megahertz by Google but failed. Is there exist one?
- 1