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The conventional macroscopic interpretation of Faraday’s law assumes that the induced electromotive force (EMF) in a winding depends solely on the time variation of magnetic flux and is independent of magnetic material properties and core length. In this work, we experimentally demonstrate that, under quasi-static excitation conditions relevant to power magnetic components, the induced EMF exhibits a measurable dependence on both the magnetic permeability and the magnetic path length of the core. Three dedicated test configurations are presented to isolate the influence of permeability, core length, and core cross-section on the induced voltage. The results reveal that variations in these parameters produce non-negligible changes in the induced EMF, and in some cases enable voltage step-up behavior without altering the turns ratio. These findings highlight practical implications for the design and optimization of high-frequency transformers and magnetic components, suggesting that material and geometric factors play a more direct role in induction than typically assumed. The study motivates a refined examination of macroscopic electromagnetic induction laws, particularly regarding their treatment of magnetic media.