Falling glass with water emits a strong jet

This is a surface tension phenomenon, that in some cases a falling (from 2cm height) test-tube emits a strong water jet. This is caused by the fact that instantly zeroed g (in the tube's frame) creates a large surface tension meniscus at the edge, and then it hits a water causing this g to rize rapidly to create a converging radially-symetric wave, which, increases when approaching the center (unlike the normal, diverging wave).

It reaches infinity in the center, which is how the jet is formed. In this video, this process is captured using a repeated-experiment timelapse video, with resolution of 800us (microseconds). Reflections from the tube's glass surfaces were reduced to minimum by using two polarizers (both the flash and the camera) perpendicularly oriented.

Notice the huge air bubble trapped inside the inward-broken wave. This is something we didn't know about.

(Additional credits go to Yoav, Amir, Eli, Amnon and Michael)

Category:

Howto & Style

Tags:

• physics
• timelapse
• repeatedexperiment
• water
• gravity
• surfacetension
• polarization
• glass
• jet
• waves
• highspeed
• slowmotion

[Kai327]

lol i Love the awesome science youtube vids like making bubbles from dry ice and soap... or like instant freezing water/beer with a tap done by supercooling them =)

[skullsamurai]

this is friggin cool!!

[AtomicCombustion]

This is really neat, I wish it was longer.