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Using a finite-element method, we have calculated fluxmetric and magnetometric demagnetizing factors [N.sub.f] and [N.sub.m] for square cross-section bars as functions of susceptibility [chi] and length-to-width ratio c/a over the range [chi] = -1 to [infinity] and c/a = 0.01 to 100. We present the results in figures and tables and compare them with those for cylinders. We give an approximate conjugate relation for [N.sub.m]([chi]) of a cube. Index Terms--Fluxmetric and magnetometric demagnetizing factors, square bars.

We evaluate, using exact general formulas, the fluxmetric and magnetometric demagnetizing factors, [N.sub.f,m], of a rectangular prism of dimensions 2a x 2b x 2c with susceptibility [chi] = 0 and the demagnetizing factor, N, of an ellipsoid of semiaxes a, b, and c along the c axis. The results as functions of longitudinal and transverse dimension ratios are listed in tables and plotted in figures. The three special cases of b [much greater than] [(ca).sup.1/2], b [much less than] [(ca).sup.1/2], and a = b are analyzed together with the general case, to quantitatively show the validity of approximate formulas for special cases. [N.sub.f,m] of prisms with any given values of [chi] may be estimated to an accuracy about 10%, since 1) [N.sub.f,m] of prisms with a = b are very near those of cylinders, for which the [chi] dependence has been calculated quite completely; 2) the [chi] dependence of the transverse [N.sub.f,m] of prisms with b = [infinity] (rectangular bars) have recently been calculated completely; and 3) [N.sub.f,m]([chi] = [infinity]) for prisms of great longitudinal dimension ratios are close to N of the corresponding ellipsoids. Thus, the existing very incomplete results can be used in some cases satisfactorily, although much work has to be done before the actual [chi] dependence of [N.sub.f,m] is available as it is for cylinders. Index Terms--Cylinders, demagnetizing factors, ellipsoids, prisms.

The radial magnetometric demagnetizing factor [N.sub.mr] of a disk is calculated from the corresponding axial factor [N.sub.ma] as a function of the ratio of thickness to diameter t/d and the susceptibility of material [chi] by the formula [N.sub.ma] (t/d, [chi] = [chi]* + 2[N.sub.mr] [t/d, [chi] = -[chi]*/(1 + [chi]*)] = 1 + [delta](t/d, [chi]*). This formula is derived from the magnetostatic laws with a correction (|[delta]| [much less than] 1) based on known values of [N.sub.ma] and [N.sub.mr] for [chi]* = [infinity]. The accuracy of the [N.sub.mr] thus obtained is estimated to be better than 1%, which satisfies most practical needs. Index Terms--Demagnetizing factors, disks.

Presents a study that evaluated the flux metric and demagnetizing factors of a rectangular prism and an ellipsoid of semiaxes. Background on the study of demagnetizing factors of homogeneous bodies; Assessment of the demagnetizing factors using a wide range of dimension ratios; Results and implications.