How to Make a Parabolic Mirror: Bernoulli and Euler Equations

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A paraboloid, like you would use to make a parabolic mirror for a zenith telescope, is an enormous pain to machine at ultrahigh accuracy but very simple to make if you are starting with liquid, because liquid in a container rotating in solid-body rotation makes a paraboloidal surface. So you put a tank on a pottery wheel and spin it.
That's fun but -- this flow also is a special case in which you can separately integrate each of Euler's inviscid flow equations along the Frenet-Serret apparatus i.e. in streamline coordinates -- the streamwise direction (Bernoulli equation) as well as the normal (radial) and binormal (vertical) directions.
Also you can stack as many immiscible fluids as you want to make a stripey paraboloidal thingy. Here I stack fluorinert, water, and canola oil to make... I dunno. A sideways flag of the Canary Islands?
Also don't miss the goldfish and Alka-Seltzer.
This video series is called "Professor Kirby's Fluid Mechanics Kitchen" because the high-powered consultants I hired said that "Professor Kirby's Fluid Mechanics Kitchen" would never be confused with anti-vaxxer code words by Google's AI algorithms. Rather than my kitchen, this video was recorded in Duffield Hall at Cornell, right next to the Electrical Engineering department and the Cornell Nanoscale Science and Technology Facility. Patrick Wick made the setup and was videographer and can be seen in the GoPro video when the tank rotates.
Lectures are from Cornell University Mechanical Engineering 3230 - Introductory Fluid Mechanics. For reference information, especially how I teach it in MAE3230 at Cornell, see "How Fluids Work", Brian J. Kirby at Amazon: smile.amazon.c....
The music in the series is the music I listened to when I was doing my fluid mechanics homework back in the day. In this video, it is Quasimoto "Rappcats" and Pharcyde "Drop". Now that I think about it, Rappcats came out when I was an assistant professor. The music in the series seems to also include the music I listened to when I was writing my NSF CAREER proposal.