34
votes
At what speed does information move through the atoms of a rigid object?
A mechanical impulse will travel along an iron bar at the speed of sound (which will depend on the material and also possibly on the frequency and amplitude of the impulse). But in the video the ...
- 47.5k
14
votes
At what speed does information move through the atoms of a rigid object?
The question in the title is formally contradictory. A model is always a simplification of the real world for the sake of understanding and making predicions (usually mathematically) A "rigid ...
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11
votes
Accepted
Is the speed of causality slower in water?
The speed of causality in water is still $c$. Although light does not travel at $c$ in water, it is possible to have particles travel through water faster than light does. Such particles emit a ...
- 94.5k
5
votes
Is the speed of causality slower in water?
The "speed of light" inside a medium refers to different things, so they can't all be the speed of causality.
First, there are the group and phase velocities. In a medium where the index of ...
- 1,892
5
votes
Why does phase get kicked back during refraction?
We start by determining the field due to to a sheet of charges harmonically oscillating in phase with frequency $\omega$, and then relate its phase to the incident field that causes this motion. ...
- 11.9k
3
votes
Why does phase get kicked back during refraction?
It is because of the surprising fact that the radiation part of electric field of an oscillating plane of (positive) charge on the line perpendicular to the plane is proportional to minus velocity of ...
- 35.5k
2
votes
Is the speed of causality slower in water?
The main thing to note is that when electromagnetic waves propagate in some medium other than vacuum, then the medium itself may be driven by the electromagnetic waves into some wave-like oscillation. ...
- 56.7k
2
votes
Is the speed of causality slower in water?
Different wavelengths of visible light travel in water at different speeds. This is why we have rainbows (as well as other important things).
Does it mean that causuality for red events happens at ...
- 7,628
2
votes
Is the speed of causality slower in water?
Although your question only concerns water and other such media, it can also be directly associated with Maxwell’s equations showing that c is inversely proportional to the permeability and ...
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1
vote
How will light refract if it falls at the corner of a rectangular glass slab
You have drawn a single ray. But that isn't all of the light. Light is a wave, and waves are spread out. You draw rays to show the direction the wave is traveling.
Some of the wave will hit side AB ...
- 36.3k
1
vote
Why does the different speed of light in different media cause refraction?
Is there a macro phenomenon, say a stream of bullets, that will also bend as it changes from one medium to another or is light somehow unique?
If you drive a car off of a smooth hard road onto a soft ...
- 94.5k
1
vote
Refractive index of titanium dioxide films as a function of wavelength for 400 C ° annealed films
I am not sure which spectrophotometer you are using, but the data looks reasonable from my perspective.
I am not sure why you would get directly a measurement of the refractive index from the ...
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