2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/29941The magnetic characteristics for superconducting samples of different geometries (plates and films of various widths) and orientation with respect to external field are compared. A similarity is established between the magnetization curves M(H) and the corresponding susceptibilities. A sign reversal is predicted for the 3rd harmonic of the ac susceptibillity when the irreversibility mechanism changes from bulk pinning to edge barrier. A mutual influence of the edge barrier and bulk pinning on the magnetization curves and field-dependent ac susceptibility is studied on the basis of an exactly solvable model (narrow plate in a parallel field and/or narrow film in a perpendicular magnetic field).24 pages, 10 figuresSuperconductivitytext