Stone skippingStone skipping
is a pastime which involves throwing a stone
with a flattened surface across a lake
or other body of water. The object of the game is to see how many times a stone can be made to bounce before sinking.
The pastime is also called stone skipping and ducks and drakes in England and stone skiffing in Ireland.
The current world record according to the Guinness Book of Records is 38 skips, set by Jerdone Coleman-McGhee in 1992.
Research undertaken by a team lead by French physicist Lydéric Bocquet has discovered that an angle of about 20° between the stone and the water's surface is optimal. Bocquet and his colleagues were surprised to discover that changes in speed and rotation did not change this fact.
Earlier research reported by Bocquet calculated that the world record of 38 rebounds required a speed of 12 m/s (25 mph), with a rotation of 14 revolutions per second.