🔬#MESExperiments 47: Ping Pong Ball Floats in a Water Vortex when ...

In #MESExperiments 47 I have uploaded the 2018 video by The Action Lab showing a ping pong ball in a whirlpool or water vortex sinks under normal atmospheric pressure but floats inside a vacuum chamber. This is a very interesting experiment, which I wanted to test for myself but I don't have a battery powered magnetic stirrer or a clear acrylic vacuum chamber. The Action Lab's explanation is that the ping pong ball sinks in normal conditions because the fast moving rotation of the water causes a pressure drop according to Bernoulli's principle, thus the higher pressure air pushes down on the ball and water. However, inside the the vacuum chamber, the air pressure is very low so there is a smaller pressure difference, hence the ball floats.

An alternative explanation may be that the low pressure zone in the vacuum chamber where the water is rotating is enough to boil the water causing a water-vapor bubble below the ball, thus pushing it upwards. Further tests are needed to confirm this.

Vortex Vacuum.jpeg

Links original video and more info

The Action Lab video: Amazing Effect when you put a Whirlpool in a Vacuum Chamber:
The Action Lab Wikitubia: https://youtube.fandom.com/wiki/The_Action_Lab
- Channel is run by James J. Orgill whom has a PhD in chemical engineering from Brigham Young University.
Bernoulli's principle: https://youtube.fandom.com/wiki/The_Action_Lab
Alternative explanation is the "air pocket" at the bottom in a vacuum chamber is actually boiling water due to the lower pressure:
- Screenshot of comment:

Timestamps

Ping pong ball drops down in a water vortex or whirlpool created via a magnetic stirrer: 0:00
Will the ball sink or float in a vortex in a vacuum chamber? 0:45
Ball starts floating at below 0.2 atmospheres of pressure: 2:00
Ball doesn't rise completely because there is still some air pressure in the vacuum chamber: 2:37
Letting air back in sinks the ping pong ball: 2:54

Stay tuned for #MESExperiments 48...