Tip:
Highlight text to annotate it
X
Pour some water in a glass.
And then put 10 to 15 dried grapes.
The grapes flow in the water
and go down at the bottom of the glass.
A few minutes later
some grapes rise to the surface
and get back to the bottom of the glass.
Some grapes can come up to the surface
and flow down several times
This phenomenon continue during a few minutes.
When we put the grapes in the water,
they drop to the bottom
because they undergo the Archimedes's principle
lower than their weight
carbon dioxide bubbles
escaping from the sparkling water
can hook the grapes
thanks to their rough surface.
The grape becomes lighter than the water
and can raise in the water.
When the grape rises to the surface,
carbon dioxide bubles break itself
and the grape, swept along by its weigh,
get back to the bottom.
Production: University of Lille 1 - Sciences and Technologies
SEEM Multimedia Service - University of Lille 1
The Online Thematic University for Sciences
Teachers/ Researcher: Jean-Marie Blondeau, Bernard Bonnel
Project coordinator (shooting and editing): Bernard Mikolajczyk
Technician: Gerard Destrun
Voice over: Alain Nempont
Contact: semm@univ-lille1.fr