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How fast would you have to travel to be able to run on water? (cont鈥檇)

Paul Greenwood
Lugano, Switzerland

You can 鈥渞un鈥� on water by being pulled behind a speedboat on waterskis, and it is even possible to do this barefoot, although it requires a fast boat. When you do this, you are standing on a fast-moving stream of water, rather than actually walking. The relative speed between the water and the skier is horizontal, but the angle between the feet and the water deflects water downwards, creating an upward reaction force on the skier鈥檚 foot. The speed required depends on your weight and the size of your feet. For most adults, you need to be travelling at about 55 to 60 kilometres per hour, although I once taught an 11-year-old to do it at 45 km/h.

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