Statistics for Relative permeability ?r of a ferrite rod can be determined by finding the series resonant frequencies of a simple L-C-R circuit with and without the rod inside the inductance coil. Compared to other methods employed for the determination of permeability, this method is simple and easy to perform in the laboratory. Using the value of ?r from this experiment, ?o—the absolute permeability of free space has been determined which provides a check for the correctness of this experiment. © 1972, American Association of Physics Teachers. All rights reserved.