All Questions
14
questions
15
votes
6
answers
7k
views
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
11
votes
1
answer
850
views
Refractive index of water
The index of refraction is given by the following formula:
$$
n = \sqrt{\frac{\epsilon \mu}{\epsilon_0 \mu_0}} = \sqrt{\epsilon_r \mu_r},$$
where $\epsilon_r$ is the relative permittivity/dielectric ...
- 665
1
vote
0
answers
21
views
Why does frequent remain constant in refraction? [duplicate]
So at school the told us that:
V= f x λ
In refraction we were told that direction,speed and wavelength changes when a wave crosses different mediums, and on another occasion that frequency is the ...
- 11
0
votes
1
answer
238
views
Why is the refractive index of blue light larger than red light in water while the refractive index of radiowaves is larger than both?
So I thought the reason why radio waves have a relatively high refractive index in water is because they have a low frequency which increases the permittivity, but blue light that has a higher ...
- 103
1
vote
1
answer
64
views
Frequency of EM waves
When light travels in air, all the component frequencies of light travels with the same velocity $v_{air} = 1/\sqrt {\epsilon_0\mu_0}$ (where $\epsilon_0$ is independent of frequency. Then we say that ...
- 453
15
votes
6
answers
6k
views
Why are red and blue light refracted differently if they travel at the same speed in the same medium?
When I look at Snell's law
$\frac{\sin\theta_2}{\sin\theta_1} = \frac{v_2}{v_1} = \frac{n_1}{n_2}$
I don't see any reference to wavelength.
If red and blue have the same speed in the same medium, why ...
-1
votes
1
answer
53
views
Confusion on the indice of refraction: is it dependent on the frequency or not? [duplicate]
I saw in my course than when light hit a medium, it makes some dipole oscillating with the same frequency as the one of the light $\omega$. By a classical mechanics reasoning, one can show that the ...
- 183
1
vote
2
answers
193
views
Is it possible to reduce the speed and frequency of a light wave to zero in a liquid medium?
Assume that two mirrors are located in a huge liquid medium – say, deep down on an ocean floor – with a refractive index of $n'$ as measured by an observer $A$ standing on the beach platform at rest ...
- 2,503
2
votes
1
answer
1k
views
Microwaves in other media
I saw a video on how microwaving grapes make plasma. He said that the refractive index of microwave is about 10 inside the grape. Now, we don't know the wavelength of the microwaves in the grape or ...
user167524
0
votes
1
answer
75
views
Confusion regarding light [duplicate]
I have two question about light:
When a light wave travels from free space to a medium then there is a change in the amplitude. Why?
when a wave changes its medium then its frequency does not change ...
- 29
1
vote
1
answer
2k
views
Why is the speed of light the same for all colors in a vacuum but different depending on the color when light goes through a non-air medium? [duplicate]
I know that red light travels faster in non-air mediums than blue light because of its wavelength, but I'm not understanding why this doesn't happen in a vacuum? This is related to the topic of ...
- 33
1
vote
1
answer
601
views
Frequency dependence of electromagnetic reflection
I was surprised to see that the Fresnel equations for reflection depends on refractive index and angle of incidence, but they do not depend on frequency. Why is this case? Are they restricted to ...
- 87
61
votes
4
answers
32k
views
Why do prisms work (why is refraction frequency dependent)?
It is well known that a prism can "split light" by separating different frequencies of light:
Many sources state that the reason this happens is that the index of refraction is different for ...
- 12k
41
votes
4
answers
192k
views
Why does wavelength change as light enters a different medium?
When light waves enter a medium of higher refractive index than the previous, why is it that:
Its wavelength decreases?
The frequency of it has to stay the same?
- 4,607