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HEIGHT
SYSTEMS
GEOPOTENTIAL NUMBERS
GEOPOTENTIAL NUMBERS
The geopotential
number of a point is a measure of the difference in potential from the reference surface to the
equipotential surface passing
through the point
›The geopotential
number is numerically equivalent to the work required to raise a mass of 1 Kg against gravity (g) through the
orthometric height (H) to
the point:
H
›Geopotential number
(C) = g dH
0
›The difference in
height (dh) measured during each setup of leveling can be converted to a difference in potential by multiplying
dh by the mean value of
gravity (gm) for the setup
›Geopotential
difference = gm*dh
