An induction cooktop uses magnetic energy to heat cookware. The heating elements in induction cooktops are not electric coils or burners, but powerful electromagnets. When an element is switched on, the corresponding electromagnet generates a magnetic field. When a magnetic utensil is kept on top of the cooking surface, the magnetic field from underneath induces an electric current through it. Iron forms a large percentage of the composition of ferromagnetic utensils. Iron is a poor conductor of electricity and resists the flow of current. The ferromagnetic utensil generates resistance to the current, resulting in the production of thermal energy.
To cook on an induction cooktop, you can use only cookware made of ferromagnetic materials, such as cast iron and steel. Though stainless steel contains a large percentage of iron, not all stainless steel cookware is magnetic, and only certain varieties can be used on an induction cooktop.
You can also use colored cookware on induction cooktops, so long as the material is magnetic. Such cookware is usually covered with enamel finish to make them more attractive.
You can not use cookware made of aluminum or copper unless it has been modified to accommodate a magnet underneath the layers. Glass cookware cannot be used on an induction cooktop under any circumstances. If you place a non-magnetic utensil on an induction cooktop, it will be unaffected by the magnetic field being generated by the electromagnets underneath the surface of the cooktop. As a result, it will not heat up.
Testing Induction Readiness
When you plan to buy cookware, perform a simple test to judge its suitability. If a magnet sticks to the bottom of the cookware, it will work on your induction cooktop. But if the attraction does not exist or is weak, it will not heat up due to magnetic energy.
If you buy online, you can not perform the magnet test, so you must never buy cookware that is not explicitly described as "induction ready." If you are getting a good deal online, you can try and find the same cookware model in a nearby store, and test it there. If it works, you can safely buy it online. Also look for warranties and refund policies on induction cookware so that if something goes wrong, you have an option to return or exchange your cookware.
Try to look for cookware with smooth flat bottoms. The bottom of the cookware must be completely aligned to the cooktop, or it will not heat properly. Rough bottoms can cause scratches on the cooktop surface, which are hard to remedy.
Never slide cookware on the surface of an induction cooktop, as this can also cause damage. In such cases, the warranty may not cover your costs, and you may have to spend more money on repairs or replacements. Proper usage of magnetic cookware is essential for the maintenance of your induction cooktop, so choose your induction cookware with care.