Eddy Currents

Eddy currents are closed loops of induced current that circulate within the bulk of a conductor when it is exposed to a changing magnetic flux, dissipating energy as heat through the conductor's resistance. An induction stove drives a high-frequency alternating current through its coil, producing a rapidly changing magnetic field at the cooktop surface. In the steel pan, this changing flux induces strong eddy currents whose ohmic dissipation (I^2R) heats the metal directly. Glass, being an electrical insulator, offers no free charge carriers for such currents to flow, so essentially no eddy-current heating occurs and the dish stays cool. The option about reflection misattributes the effect to wave optics rather than induction. The ferromagnetic-storage option is wrong because fields are not stored permanently and hysteresis is secondary here. The conduction option ignores that the coil itself does not touch the pan and transfers energy by induction, not contact. This is precisely the eddy-current application NCERT cites for induction heating, where laminating or insulating a core is used elsewhere to suppress such currents but a solid pan is chosen here to maximise them. A consistency check notes that any good conductor placed there would heat, while any insulator would not, confirming that bulk electrical conductivity is the single deciding factor.