All Questions
Tagged with refraction special-relativity
68
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Does time pass slowly in water?
In water the speed of light is slower than it is in vacuum. By special relativity the speed of light is constant. Typically, for the basic explanation of special relativity a clock which has a mirror ...
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Is the relativistic energy-momentum relation fundamental? [duplicate]
The following relativistic energy-momentum relationship is taken to be fundamental:
$$E^2=p^2c^2+m_0^2c^4.\tag{1}$$
Let us specialize to massless particles ($m_0=0$) so that we have:
$$E=p\ c.\tag{2}$$...
- 207k
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Does light accelerate? [duplicate]
If considering the general formula for acceleration, ie.
Δ V/ΔT, we would get zero as the velocity of light is constant and does not change.
However, what about when photons travel through different ...
- 207k
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Is it possible to distinguish the type of space according to the speed of light in vacuum? [duplicate]
Why is the speed of light 300 000 km/s? The speed of light is slower in glass, water and diamond. Is the speed of light in water, glass and diamond also absolute? Can we calculate the material such as ...
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Do photons moving at $c$ slow down when entering a medium or take a longer path and only appear to slow down and what happens to time? [duplicate]
Imagine a photon leaving a vacuum and entering a medium, say, air. I have 2 questions:
Some claim that the photon is slowed by the medium so its speed becomes less than $c$. Is that true or does ...
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Relativistic Effects on Electromagnetic Wave Propagation
So for a recent lab I had to calculate the length of a conductor by measuring the time it took a signal to reflect off of the open end. I used the very simple principle of $v=st$ and, knowing that the ...
- 207k
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How does a refractive index of less than one not violate relativity?
If I am not mistaken, this video says that X-rays travel faster in glass than in a vacuum. Special Relativity says that information can not travel faster than the speed of light in a vacuum, so what ...
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Mass density of photons in a refractive medium
The effective mass density of photons in a vacuum $\rho^{vac}_M$ is related to the photon energy density $\rho^{vac}_E$ by
$$\rho^{vac}_M=\frac{\rho^{vac}_E}{c^2}.$$
Is it true that the mass density ...
- 9,367
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Photon energy-momentum relation inside a material [duplicate]
I understand that the speed of light in a medium like glass, $c_n$, is reduced by the refractive index $n$ so that we have:
$$c_n=\frac{c}{n},$$
where $c$ is the speed of light in the vacuum.
Is it ...
- 5,925
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Do quasiphotons have mass?
If I understand correctly, per special relativity, anything that travels at a speed of $c$ must be massless and conversely, anything massless must travel at precisely $c$ in akl reference frame. We ...
- 60.3k
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Stellar aberration in a water-filled telescope
I read that when the stellar aberration of light is measured with the help of a telescope filled with water, the value of the aberration is equal as in the case of a telescope filled with air.
Just ...
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What does light travel through or why it is independent of a medium? [duplicate]
According to my research and understanding I cant get over the fact that light needs no media to travel, or is it scientifically or mathematically proven?
- 24.5k
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3
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Does the speed of light in different mediums affect the Lorentz transformation?
We know that the Lorentz transformation is derived using the speed of light in a vacuum. But if we were to use it in water, would it change since the speed of light in water should also remain ...
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1
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What is the acceleration of light (photon) in vacuum? [duplicate]
We all know that the speed of light is 299792458m/s, but what is the acceleration of photons? That is to say, does the photon have a speed transition from zero to the speed of light?
- 207k
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Is the speed of light in is uniform non-vacuum medium constant for all observers? [duplicate]
I am running at $5 \text{ ms}^{-1}$ and holding a torch pointing in the direction of motion. This torch has a large block of glass attached to the end. Would a stationary observer see the light as ...
- 9,611