What determines the performance of a ferrite core at different frequencies?
Its conductivity
Its thickness
The composition, or “mix,” of materials used✓Bonne réponse
The ratio of outer diameter to inner diameter
Explication
A ferrite's permeability and loss with frequency are set by the recipe of oxides it is made from, which is why cores are sold by mix number for a given frequency range. Physical dimensions change the inductance obtained, but not the frequency behavior of the material.