Induction cooktops utilize a unique method of heating that is different from traditional stovetops. Instead of using direct heat transfer through a flame or electric coil, induction cooktops generate an electromagnetic field.
Here's how it works:
Electromagnetic field: When you turn on an induction cooktop, an alternating current is passed through a coil beneath the glass surface. This current creates a rapidly alternating magnetic field.
Induction effect: When a compatible cooking vessel, such as one made of ferrous (magnetic) material like cast iron or stainless steel, is placed on the cooktop, the alternating magnetic field induces electric currents within the vessel.
Resistance heating: These induced electric currents encounter resistance within the metal vessel, generating heat. This heat is produced directly in the bottom of the cooking vessel due to the resistance of the metal, rather than through the transfer of heat from an external source.
Magnetic field containment: The induction cooktop's design focuses the magnetic field within the cooking zone, ensuring that most of the energy is concentrated on the bottom of the vessel. The field does not extend significantly beyond the boundaries of the vessel.
As a result of this process, the heat generated by the induction cooktop is efficiently transferred to the cooking vessel itself. The vessel, in turn, transfers the heat to the food inside through conduction. The surrounding air and the rest of the vessel remain relatively cool because the heat is not radiated or conducted to them directly.
It's worth noting that while induction cooktops are highly efficient at heating cookware and food, they require the use of compatible magnetic materials for effective heat generation. Non-magnetic materials like aluminum, copper, and glass do not interact with the magnetic field and, therefore, do not heat up directly on an induction cooktop.