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Why does water follow the spoon's surface?

Is the reason surface tension, viscosity effects, a pressure gradient?

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    $\begingroup$ Almost definitely surface tension $\endgroup$
    – RC_23
    Commented Oct 1, 2021 at 20:10

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The relevant forces are adhesion (the attractive force between dissimilar molecules) and cohesion (the attractive force between similar molecules). Adhesion sticks the water molecules close to the metal-water interface to the metal. Cohesion sticks the water molecules far from the metal-water interface to the water molecules close to the metal-water interface.

Surface tension (the bulk force difference between the air side of the air-water interface, where there is no cohesion force, and the water side of the air-water interface, where there is a cohesion force) plays a minor role: it keeps the shape of the stream roughly dome shaped.

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  • $\begingroup$ if bore tiny hole at spoon at 1/4 chord and meassure static pressure,will manometar read lower pressure than atmosphere pressure? $\endgroup$
    – 22flower
    Commented Oct 2, 2021 at 8:44

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