On a superhydrophobic surface,
N identical, nearly spherical liquid droplets of radius
r coalesce simultaneously into a single droplet. Surface tension stores a fixed energy per unit area, and assuming
100% conversion of the released surface energy into translational kinetic energy, the merged droplet jumps to height
hN. Let
h2 denote the jump height for
N=2, and let
h∞=limN→∞hN (with
r fixed). What is the ratio
h∞/h2?