Page:The Mathematical Principles of Natural Philosophy - 1729 - Volume 1.djvu/396

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If a olid be plane one one ide, and infinitely extended on all other ides, and conit of equal particles equally attractive, whoe forces decreae, in the reces from the olid, in the ratio of any power greater than the quare of the diŧances; and a corpucle placed towards either part of the plane is attracted by the force of the whole olid; I ay that the attractive force of the whole olid, in the attractive force of the whole olid, in the reces from its plane uperficies, will decreae in the ratio of a power whoe ide is the ditance of the corpucle from the plane, and its index les by 3 than the index of the power of the ditance.

Let LGI (Pl. 24. Fig. 6.) be the plane by which the olid is terminated. Let the olid lie on that hand of the plane that is towards I, and let it be reolved into innumerable planes mHM, nIN, oKO, &c. parallel to GL. And firt let the attracted body C be placed without the olid. Let there be drawn CGHI perpendicular to thoe innumerable planes, and let the attractive forces of the points of the olid decreae in the ratio of a power of the ditances whoe index is the number as not les than 3. Therefore