Electromagnetic deceleration of metallic spheres

The author reports the results of an approximate model of the potential of static magnetic fields, producible by permanent magnets, to decelerate spherical metal samples by eddy currents induced in the materials. It is assumed that the velocity of the sample is low enough that the magnetic field diffusion time is significantly less than the time required for the samples to pass through a half cycle of the magnetic field. Thus, the interaction between the sample and the field will be fully resistive, and the sample´s kinetic energy will be converted directly into heat by joule heating. The mode incorporates the effects of magnetic field strength and system geometry, and it predicts that a useful braking device can be constructed. The results of the theoretical analysis are also compared against preliminary tests using a laboratory model