Can a yacht ever travel faster than the wind?

Asked by: George Jeffries, St Albans

This seems like defiance of the laws of physics, but it just needs the right shape and size of sail to trap enough of the air-mass blowing in the wind. The resulting transfer of momentum can propel yachts to impressive speeds, especially if friction is minimised – some sleek catamarans can achieve 80km/h using 35km/h winds.

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