230. Video of the day: viscosity or the arrow of time is reversible
APPLIED, ASTRO — By Dmitry Podolsky on February 5, 2009 at 3:56 pm
Save This Post as PDF
A lot of fun to watch 
CP is clearly conserved in this experiment LOL
LM explanation of the effect: The reason why it looks counterintuitive is the people normally confuse chaotic motion and organized motion.
The entropy growth in the system is extremely slow – you can see that the droplets don?t change too quickly at the beginning, and you can predict how much they would change in 2 minutes.
The systematic motion inserted into the system is non-chaotic and completely reversible, and because of the high viscosity, it doesn?t strongly help the droplets to mix microscopically with the environment.
So it?s completely analogous to stretching a piece of rubber by a lot, and releasing it, allowing it to return to the original shape. Of course that the system will almost return where it was, and the only dissipation is the slow one that could be observed at the very beginning.
1 Comment
Haha, very funny. The reason why it looks counterintuitive is the people normally confuse chaotic motion and organized motion.
The entropy growth in the system is extremely slow – you can see that the droplets don’t change too quickly at the beginning, and you can predict how much they would change in 2 minutes.
The systematic motion inserted into the system is non-chaotic and completely reversible, and because of the high viscosity, it doesn’t strongly help the droplets to mix microscopically with the environment.
So it’s completely analogous to stretching a piece of rubber by a lot, and releasing it, allowing it to return to the original shape. Of course that the system will almost return where it was, and the only dissipation is the slow one that could be observed at the very beginning.
Trackback responses to this post