146During testing of technological processes, it is often necessary to obtain information on the states of mag netized objects (in particular, magnetic dipoles) that are positioned behind a flat ferromagnetic obstacle. The wall of a ferromagnetic container may serve as such an obstacle. In connection with this, the question of the penetration of a constant magnetic field through such an obstacle arises. The case of the penetration of a magnetic field (MF) through a closed ferromagnetic shell was considered in detail in the theory of magnetic shielding [1]. If the ferromagnetic obstacle is not closed, its influence on the transmission of a static MF is not very obvious. In the well known classical manuals on magnetism [2, 3], it has been shown that a flat fer romagnetic plate in a homogeneous static MF does not manifest itself in any way, i.e., it is not a barrier for this field. However, this statement is valid only for a homogeneous field. In an inhomogeneous field (as, in particular, the field of a point dipole), concentric magnetic poles arise at the points where lines of force enter the ferromagnetic plate and emerge from it. The field of these poles may substantially distort the initial field and thus exert either an attenuating or intensifying effect on it. This effect was considered in [4] and [5] using the mirror image method and the method of solving the Laplace equation, respectively. Unfortunately, in both of these cases, the studies were performed for plates whose dimensions were not limited. In addition, the data presented in [5] are insufficient for use in particular calculations. This paper presents the results of an experimental study of the influence of a ferromagnetic disk with finite dimensions on the field of a magnetic dipole that is positioned on the symmetry axis of a disk with a magnetic moment that is perpendicular to the disk plane. Figure 1 shows a point magnetic dipole with a moment that is perpendicular to the plane of a disk, which is positioned on its axis of symmetry. Under the action of the dipole field (on the disk surface), con centric circular magnetic poles ("magnetic charges") arise at the points where lines of force enter the fer romagnetic plate and emerge from it. The fields of these poles are vector summed with the initial dipole field, in particular, at the point K (Fig. 2). The axial field component, H S , from the South pole has the same direction as the initial field, H 0 , while the direction of the field component from the North pole, H N , is opposite relative to the initial field. The influence of the axial field component from the North pole (when magnetic charges have equal magnitudes) is higher than the influence of the component from the South pole because of the difference in the distances to the point K and the difference between the angles Abstract-The distorting effect of a ferromagnetic disk of finite dimensions on the constant field of a magnetic dipole is considered. It is shown that, depending on the mutual arrangement of the dipole and disk, the dipol...