It's good to see that French scientists are hard at work on important problems.
Want to skim the perfect stone? A team of French researchers have worked out how, using their very own stone-skipping machine. ...Incredible! That's not at all close to the angle people normally try to use to skip stones. Is angle all that matters?
To achieve the maximum number of rebounds, the angle between a spinning stone and the water should be about 20 degrees1, advises Clanet: "This is the magic angle."
Spin, speed and shape are also important. A stone is more likely to rebound if it is rotating, they found. This is because spin stabilises the object and prevents it from falling into the water.Amazing stuff.
Speedy stones are more likely to bounce than sluggish ones. A five-centimetre disc approaching the water at the magic angle needs to fly faster than 2.5 metres per second in order to avoid taking a plunge. Flat, round discs are ideal as their large surface area creates bounce on impact.