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Cake day: July 4th, 2022

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  • I don’t remember all of the details, but I thought it was essentially the water’s surface tension that foots the energy bill when climbing a paper towel or a capillary in a tree.

    The surface of fluids like water are unhappy. Molecules on the surface would much rather be deep in the fluid because on the surface they have “dangling” Van der Waals & polar bonds to one side. You can calculate the potential energy of the surface due to all of those dangling weak bonds, & that’s the energy that is used to climb a capillary (the energy isn’t free).

    I could be misremembering though, I admit. School was many years ago…