5. Water dancing ball

When a ball lying on a hard and flat surface is hit by a jet of water that falls perpendicular to the surface, it may start to oscillate. Investigate how the oscillations depend on the relevant parameters.

	Report	Opposition	Review
Colombia			8.00
Croatia			7.00
Denmark	7.25		7.60
France – Université de Lyon	8.60	6.80	6.67
France – École polytechnique		7.50 7.00
Germany	6.00
Greece			6.00 6.40
India	4.40		6.00
Italy	5.80	7.40
Poland		6.60
Russia – MIPT		5.60
Sweden	5.20
Switzerland		7.80	6.80
USA		5.40
Ukraine - National University of Kharkiv	8.60 6.50	8.00	7.60
Ukraine - TSNUK	5.60

MEAN

6.44

6.90