Strange Rotational Behavior

[Duman]

I've seen a lot of things, but this one took my by surprise when I came across it on Youtube.

A rotating object flipping direction, appearing to violate conservation of momentum. Never saw this in school.


https://www.youtube.com/watch?v=1VPfZ_XzisU

[Gman]

Irving posted this up a while back. I think it might be in the cool video thread.

ETA: It was brutal that posted this up in the video thread: https://www.ar-15.co/threads/146129-Amazing-and-Cool-Video-Thread?p=2244529&viewfull=1#post2244529

Irving also posted it in the Post Whore Thread.

[Irving]

Veritasium has a bunch of cool videos. As well as Smarter Everyday, Steven Mould, Vsauce, Practical Engineering, etc.

[Duman]

My apologies, I didn't realize it was posted previously.

[MrPrena]

Didnt watch entire video, it is 3d, and it has X-axis Y-axis and Z-axis at Cartesian coordinates.
If ZERO force applied to 1 axis, it will just spin 1 way.

Credit :Thanks my High school Physics teacher from 90s.



Now, if you want to talk detail mechanical/classical movement in Jupiter with much higher atmospheric pressure + You drop it from 1000 ft from top, and you try to hit a spinning racquet with tennis ball in the middle of spin, it requires 20%er. :D

[Irving]

My apologies, I didn't realize it was posted previously.

No need to apologize for spreading cool stuff bub.

[CS1983]

No need to apologize for spreading cool stuff bub.

Repetitio est mater studiorum

[Duman]

Didnt watch entire video, it is 3d, and it has X-axis Y-axis and Z-axis at Cartesian coordinates.
If ZERO force applied to 1 axis, it will just spin 1 way.

Credit :Thanks my High school Physics teacher from 90s.

Now, if you want to talk detail mechanical/classical movement in Jupiter with much higher atmospheric pressure + You drop it from 1000 ft from top, and you try to hit a spinning racquet with tennis ball in the middle of spin, it requires 20%er. :D

That's ok if the moment of inertia is identical in all 3-axes. The asymmetry of MOIs gives rise to the flipping of the spin vector.

[Gman]

No need to apologize for spreading cool stuff bub.

Yep. Just providing some context.

[brutal]

Irving posted this up a while back. I think it might be in the cool video thread.

ETA: It was brutal that posted this up in the video thread: https://www.ar-15.co/threads/146129-Amazing-and-Cool-Video-Thread?p=2244529&viewfull=1#post2244529

Irving also posted it in the Post Whore Thread.

My posts usually follow Irvings posts after I've gone down a rabbit hole watching his.

Last few days it's been Project Farm. Check him out. I'm making a dang list from his tests.

[Gman]

Project Farm is a regular stop for me on YouTube. Same goes for SmarterEveryDay and a number of others.

[Duman]

I'll look into Project Farm, it sounds interesting.

The last week or so I've watched Youtube videos on the derivation of euler's number, klystrons, magnetrons, and radar.
Having a general idea of how something works is good but a detailed description (sans mathematics) is better.

I like the mathematical history explanations. I was trying to understand the Gamma function for my work and have googled many documents.
But a clear, verbal, and dynamic explanation always works better for me.

The strange tennis racket rotation is a looong video but worthwhile, towards the end explains why the earth's spin vector won't flip.

[Duman]

I'm also watching videos on induction heating for melting metal. Some people doing interesting things out there.

[Irving]

You should post them up in one of the video threads. I never quite know where to stick videos often times.