- Vorführexperimente, Videos
TOP 41 amazing tricks and science experiments
another demonstration video of the phenomenom
- Wissenschaftliche Artikel
Suction-ejection of a ping-pong ball in a falling water-filled cup
During free fall, the absence of gravity in the reference frame of the cup makes capillary forces dominant, causing the ball to be sucked into water. At impact, the high velocity ejection is due to the strong Archimedes’ force caused by vertical acceleration. In this paper, the authors study the dynamics of the capillary sinking of the ball during free fall and the ejection speed at impact, using tracking and high-speed imaging. In particular, they show that at short-time, the sinking is governed by capillary and added mass forces.
The ping-pong ball water cannon
The authors report an initial dimensional and order-of-magnitude analysis, and describe the successive experimental set-ups. The proposed explanation is confirmed by direct high-speed video observations. These videos are downloadable, too.