Euler’s Disk
An evening pause: Something for all those new home schoolers, and their parents, to puzzle over and use to learn something worthwhile and real.
Note also how the concave mirror eventually forces the disk into the center of the mirror.
Hat tip Phill Oltmann.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Highly suggest any of the physics lectures from Walter Lewin for home-schooling purposes. (High school level.)
–Get yourself a free test-copy (full functionality for 1 month) of Internet Download Manager (or similar downloading Program), download them all off yt, and burn them to DVD. (This by-passes all inserted commercials, and you have a physical copy.)
[If you want ‘mental hygiene films’ from the 1950/1960’s, go to the Archive(dot)org.
Professor Walter Lewin
“I am Still Alive Because of D-Day”
June 6, 2018
https://youtu.be/p5bsw8GNqCM
3:11
a sample….
MIT Physics 8.01x
“Lecture 6 – Newton’s Laws”
Walter Lewin
https://youtu.be/oduZsA0Tk58
49:15
“Watch all my 94 MIT course lectures. Start with 8.01, then 8.02, then 8.03. Do all the homework and take all my exams. Homework and exams are posted below the video thumbnails. I guarantee you, that you will then not fail the Physics portion of any exam.”
Now I wonder if this has a thermodynamic counterpart with “anti-freezing:”
“When vibrations increase on cooling: Anti-freezing observed”
From Aug 4 2021 phys.org at Helmholtz Association… nickel oxide.
The term anti-freezing made me think back to Egon Bach’s ideas of work and “anti-work” when it came to “geometeors” as Olkhovatov thought Tunguska was..