ACCELERATION OF GRAVITY FOR THE EARTH MODEL AS AN ELLIPSOIDAL MASS WITH NONUNIFORM DENSITY

We present a model calculation of the acceleration of gravity in an el lipsoidal mass with nonuniform density. Using parameters resembling th at of the earth's dimensions and mass density, we are able to account for most of the observed variation of the acceleration of gravity at t he pole and the equator which is not related to rotational effects. Th e nonuniformity of the density of mass, when considered with the ellip soidal flattening of the earth, is one of the most important factors t o be considered when explaining the difference of the acceleration of gravity at the pole and equator. A simple model of a flattened earth w ith a uniform mass density does not give a reasonable explanation for this variation of the gravitational acceleration. (C) 1996 American As sociation of Physics Teachers.