On Teflon, the water drop has an obtuse contact angle and beads up, whereas the oil drop has an acute contact angle and spreads into a shallower patch. For small drops with negligible Bond number, both can be drawn as spherical caps.
To compare shape at equal volume , let denote the generating sphere radius. The cap height and footprint radius are
(1)
For a fixed , these relations give a taller, narrower drop for the larger contact angle. The angles are measured inside the liquid, including the obtuse angle of the water drop.
Figure 1.
Equal-volume spherical caps on Teflon
. Original cross-sections comparing water at with oil at . The same liquid volume is used to expose the difference in shape; no particular drop size or volume was supplied in the paper. Details.

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