•An object at rest on
earth’s surface experiences both the gravitational force (g*)
and a centrifugal force (-Ω2R).
•As a result, these two
forces together result in an “apparent gravity” force (g):
•
•True gravity (g) is
perpendicular to a sphere, but the apparent gravity (g*) is perpendicular
to earth’s surface.
•Geopotential is the work
required to raised a unit mass to height z from mean sea
level: