The humans can float on water but not walk. Why?
The humans can float on water but not walk. Why?
In order to “walk on water”, the water would need to support your weight on one foot. In the case of humans, both the surface tension and the buoyancy of water are insufficient to support the weight of a person.
But, even if it did, the act of shifting weight from one leg to the other to pick one leg up and move it would result in the person either breaking the surface tension or having their weight slip out from underneath them. Try, for instance, walking on an extremely low-friction surface, like a puddle of grease, or a pond of mercury. Even on ice, a person can rarely walk “normally” since the friction of the surface is typically much less than that of the ground. This static friction is almost completely eliminated on the surface of a liquid. Slick the surface of ice with a low-melting oil, and tread extremely carefully: you will injure yourself if you try to walk on such a surface.
Therefore, the reason we can’t walk on water is because of the lack of surface tension/solidityAND the lack of friction holding the foot in place as we shift our weight during walking. Only small insects, who typically have more than two legs on the surface and are light enough to be supported solely by the surface tension of the water, can technically “walk” on water. It should be noted that even these insects do not “walk” but propel themselves about by a means that isn’t requiring them to shift their weight, such as wings which provide a force of propulsion across the low-friction surface of the water.
In order to “walk on water”, the water would need to support your weight on one foot. In the case of humans, both the surface tension and the buoyancy of water are insufficient to support the weight of a person.
But, even if it did, the act of shifting weight from one leg to the other to pick one leg up and move it would result in the person either breaking the surface tension or having their weight slip out from underneath them. Try, for instance, walking on an extremely low-friction surface, like a puddle of grease, or a pond of mercury. Even on ice, a person can rarely walk “normally” since the friction of the surface is typically much less than that of the ground. This static friction is almost completely eliminated on the surface of a liquid. Slick the surface of ice with a low-melting oil, and tread extremely carefully: you will injure yourself if you try to walk on such a surface.
Therefore, the reason we can’t walk on water is because of the lack of surface tension/solidityAND the lack of friction holding the foot in place as we shift our weight during walking. Only small insects, who typically have more than two legs on the surface and are light enough to be supported solely by the surface tension of the water, can technically “walk” on water. It should be noted that even these insects do not “walk” but propel themselves about by a means that isn’t requiring them to shift their weight, such as wings which provide a force of propulsion across the low-friction surface of the water.
