Suction-ejection of a ping-pong ball in a falling water-filled cup
Dropping a water-filled cup with a ping-pong ball inside to the ground expels the ball much higher than its initial height. 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 veloci...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
EDP Sciences
2022-01-01
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| Series: | Emergent Scientist |
| Subjects: | |
| Online Access: | https://emergent-scientist.edp-open.org/articles/emsci/full_html/2022/01/emsci210004/emsci210004.html |
| _version_ | 1818218923585175552 |
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| author | Barlet A. Malhomme N. |
| author_facet | Barlet A. Malhomme N. |
| author_sort | Barlet A. |
| collection | DOAJ |
| description | Dropping a water-filled cup with a ping-pong ball inside to the ground expels the ball much higher than its initial height. 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, we 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, we show that at short-time, the sinking is governed by capillary and added mass forces. |
| first_indexed | 2024-12-12T07:31:29Z |
| format | Article |
| id | doaj.art-3f7761f7714745719eae4daa25df9441 |
| institution | Directory Open Access Journal |
| issn | 2556-8779 |
| language | English |
| last_indexed | 2024-12-12T07:31:29Z |
| publishDate | 2022-01-01 |
| publisher | EDP Sciences |
| record_format | Article |
| series | Emergent Scientist |
| spelling | doaj.art-3f7761f7714745719eae4daa25df94412022-12-22T00:33:01ZengEDP SciencesEmergent Scientist2556-87792022-01-016210.1051/emsci/2022002emsci210004Suction-ejection of a ping-pong ball in a falling water-filled cupBarlet A.0Malhomme N.1Magistère de physique d’Orsay, Université Paris-SaclayMagistère de physique d’Orsay, Université Paris-SaclayDropping a water-filled cup with a ping-pong ball inside to the ground expels the ball much higher than its initial height. 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, we 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, we show that at short-time, the sinking is governed by capillary and added mass forces.https://emergent-scientist.edp-open.org/articles/emsci/full_html/2022/01/emsci210004/emsci210004.htmlcapillary suctionsurface tensionfree fallbuoyancy |
| spellingShingle | Barlet A. Malhomme N. Suction-ejection of a ping-pong ball in a falling water-filled cup Emergent Scientist capillary suction surface tension free fall buoyancy |
| title | Suction-ejection of a ping-pong ball in a falling water-filled cup |
| title_full | Suction-ejection of a ping-pong ball in a falling water-filled cup |
| title_fullStr | Suction-ejection of a ping-pong ball in a falling water-filled cup |
| title_full_unstemmed | Suction-ejection of a ping-pong ball in a falling water-filled cup |
| title_short | Suction-ejection of a ping-pong ball in a falling water-filled cup |
| title_sort | suction ejection of a ping pong ball in a falling water filled cup |
| topic | capillary suction surface tension free fall buoyancy |
| url | https://emergent-scientist.edp-open.org/articles/emsci/full_html/2022/01/emsci210004/emsci210004.html |
| work_keys_str_mv | AT barleta suctionejectionofapingpongballinafallingwaterfilledcup AT malhommen suctionejectionofapingpongballinafallingwaterfilledcup |