Surface Tension of wood on water

AI Thread Summary
The discussion centers on the effects of surface tension on a uniformly floating cube of wood in water, which is completely wetted. It concludes that surface tension does not significantly affect the buoyancy of the cube, as the force is tangential to the liquid surface. The conversation shifts to considering a sphere instead, noting that perfect wetting creates a thin film of fluid that can still allow for buoyancy. However, it is suggested that this perfect wetting may exert a slight downward force on the sphere due to surface tension. The term "canthotaxis," referring to the behavior of contact lines at sharp edges, is also introduced as relevant to the discussion.
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Suppose a uniform cube of wood floats on the surface of water. Water wets it completely. Will it be buoyed up or down by surface tension?

The force of surface tension is tangential to the liquid surface (along the surface of liquid). So I think there is no effect on buoyancy of cube due to surface tension.
 
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Cubes cause problems because of the edges (canthotaxis)- let's consider a sphere instead.

Perfect wetting will result in a thin film of fluid covering the sphere, but the sphere can still be buoyant. I'm not sure what parameters govern the film thickness.
 
I guess perfect wetting will result in a vertical force downwards (due to surface tension). So the sphere/cube will get buoyed down by the water (though by a small amount)
What is canthotaxis by the way?
 

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