Attraction in a Spherical Hollow

Abstract

AMONG the papers of the late Prof. Peter Alexander, of Anderson's Medical College, Glasgow, I find the enunciation of an interesting theorem in attraction. “The attraction on a particle of unit mass, in a spherical hollow in a sphere of uniform density, is at all points of the hollow parallel to the line joining the centres of the sphere and hollow, and is of constant magnitude equal to 43πcσк. Where c is the distance between the centres, σ the density of the sphere and к the attraction of unit mass on unit mass at unit distance.”