Abstract
To confirm our results obtained in our former paper that, when a prolate spheroidal cavity applied with hydrostatic pressure breaks, a cone-type distribution of initial motion with pull-sense inside may occur, as a first step, we studied in this paper elastic waves generated from a prolate spheroidal cavity when a force of harmonic type is applied. Here, prolate spheroidal coordinates are applied. As a result of numerical calculations, it is found that when the cavity becomes more slender and finally, a line source with finite length, a push-pull distribution of displacement of P wave occurs as the wave length is three times the length of the source. As forces considered here are harmonic type, we can not distinguish whether our obtained distribution is a cone-type with pull-sense inside or push-sense inside, but we can assure that push-pull distribution of initial motion might occur when waves are generated from a prolate spheroidal cavity of a certain shape whose wall is subjected to normal stress.
