Date: 5/05/2015 21:13:59
From: CrazyNeutrino
ID: 718455
Subject: Light Questions

Can the glass prism be applied to other radio frequencies?

Is the slit experiment related the prism experiment?

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Date: 6/05/2015 00:55:04
From: SCIENCE
ID: 718559
Subject: re: Light Questions

yes yes

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Date: 6/05/2015 03:58:51
From: mollwollfumble
ID: 718563
Subject: re: Light Questions

CrazyNeutrino said:

Can the glass prism be applied to other radio frequencies?

Is the slit experiment related the prism experiment?

> Can the glass prism be applied to other radio frequencies?

There’s a limit. Glass is transparent in the optical and a short way into the infra-red and ultra-violet, but further into the infra-red and ultra-violet it becomes opaque. There are other types of glasses (with different mineralogical compositions) that are used by astronomers to see further into the infra-red and ultra-violet. By the time you get past ultra-violet to x-rays, the wavelength is so short that it interacts with individual atoms resulting in diffraction rather than refraction.

Moving the other way, past infra-red to microwave, if you make the prism out of something transparent to microwaves, then it works in exactly the same way as it does for light. But here, and further on for radio waves, there’s a catch. What happens when the wavelength of the radiation becomes larger than the dimensions of the prism?

> Is the slit experiment related the prism experiment?

Diffraction for the slit experiment vs refraction for the prism. If you look down on the scale of atoms, my understanding is that it’s essentially the diffraction of light by atoms on the nanoscale that causes refraction of light on the macroscale. Note also that diffraction of light on the microscale, such as by the pits on a CD, splits light into a spectrum much as refraction does.

Slightly more complicated is birefringence, in which light of different polarisation is refracted in a different direction by the crystal lattice.

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Date: 6/05/2015 15:28:46
From: PM 2Ring
ID: 718796
Subject: re: Light Questions

From the entry for Heinrich Rudolf Hertz in the Complete Dictionary of Scientific Biography

Hertz followed up his determination of the finite velocity of electric waves by performing a series of more qualitative experiments in 1888 on the analogy between electric and light waves. Passing electric waves through huge prisms of hard pitch, he showed that they refract exactly as light waves do. He polarized electric waves by directing them through a grating of parallel wires, and he diffracted them by interrupting them with a screen with a hole in it. He reflected them from the walls of the room, obtaining interference between the original and the reflected waves. He focused them with huge concave mirrors, casting electric shadows with conducting obstacles.

The experiments with mirrors especially attracted attention, as they were the most direct disproof of action at a distance in electrodynamics. They and the experiments on the finite velocity of propagation brought about a rapid conversion of European physicists from the viewpoint of instantaneous action at a distance in electrodynamics to Maxwell’s view that electromagnetic processes take place in dielectrics and that an electromagnetic ether subsumes the functions of the older luminiferous ether.

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