17. Polarization, Polarizer

MIT 8.03SC Physics III: Vibrations and Waves, Fall 2016
View the complete course: ocw.mit.edu/8-...
Instructor: Yen-Jie Lee
Prof. Lee discusses the concept of linearly, circularly and elliptical polarized waves. He focuses on the mathematical description of polarized waves. He also shows the way to produce polarized light using a polarizer in class.
License: Creative Commons BY-NC-SA
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[@wymchihiro]

This is the most enjoyable lecture I’ve watched

[@abdshbli7215]

I love the systematic way of thinking , it's the first time done in 8.03 , we love to see more.

[@hyprk5590]

Wow. Lol. I’m very impressed that elliptical polarization is explained using the transformation of circular polarization. Because I simply memorized them in the case of elliptical polarization. I really like this way to think about and explain something. Lol

[@rangaiahkaravadi5340]

Sir, I have one doubt. In the demonstration of vertically polarized light and its filtration with vertically placed conducting rods. There are air gaps between the rods. So, some light which coming as vertically polarized one should escape through the air gaps. But on the screen, it is snowing as totally filtered or blocked by the rods, how? Some light should escape through the gaps. Is it not? How the demonstration shown is correct?

[@asmolfish1031]

Rangaiah Karavadi My guess is that the intensity of fraction of light that went through the gaps is too weak to be detected by the machine. As you can see in the demonstration with two polarizers which didn’t quite work out, the machine isn’t very good at detecting light with low intensity.

[@a.vanwijk2268]

As long as the distance between the rods is smaller than the wavelength of the source, it cannot pass through. That is why you can't see rods in the polarizer for visible light ; the wavelength is much smaller than for microwaves, hence the distance between the rods (called gratings) is much smaller.

[@aname1362]

These are great. Great lecturer, full on enthusiasm. I've gone through all these so far. But I got slightly lost here, What is "peak position" or "peak value" at 8.10 - couldn't find in text (think its something obvious I missed)

[@r_1901]

I'm just passing through, but in that drawing I'd say those periodic sequences of black lines and red lines are illustrating the crests of the light wave, spaced at the wavelength. The tops of the crests are the "peak value". It's just a snapshot. The waves are actually flowing in the direction of the arrows, from n1 into n2.

[@haah9948]

how does the boundary membrane remain unbroken during total internal reflection?

[@leyawonder2306]

55:00

[@odal6770]

If you Google Video-Swimming-pool-illusion-shows-body-separated-mans-body you will see that Snel's Law is a matter of perspective, and not a hard physical law. edit: this does not apply to total internal reflection. I think.