In an induction stove there is a copper coil under the ceramic cooking plate, whereas a particular type of inductive vessel is placed on the plate. When alternating current (AC) is passed through the coil, oscillating magnetic field is formed. As per physical law of induction this “induces” electric current. The current that passes into the metallic vessel heats up the vessel due to resistance in the metal, and the vessel in turn cooks up the food in it. (See, diagram below.)
Comparing this to a gas stove, the flame of a stove wastes certain amount of thermal energy in heating up the air along with the vessel. During tests the most efficient induction cooker took 2.58 minutes to boil a specific quantity of water, whereas the same quantity of water took 5.36 minutes to reach the boiling point on a gas stove. Thus, induction cooker may very well turn out to be a cost saver.