Clairaut's theorem (gravity)

Clairaut's theorem characterizes the surface gravity on a viscous rotating ellipsoid in hydrostatic equilibrium under the action of its gravitational field and centrifugal force. It was published in 1743 by Alexis Claude Clairaut in a treatise which synthesized physical and geodetic evidence that the Earth is an oblate rotational ellipsoid.

Source: Wikipedia — Clairaut's theorem (gravity) (CC BY-SA 4.0)