Abstract: An object has a plurality of parts, wherein each part of the plurality of parts can face a predetermined direction. A plurality of resonant circuits are mounted in different predetermined positions of the object, and have different resonance frequencies. A sending unit sends signals having a plurality of frequencies corresponding to the resonance frequencies of the plurality of resonant circuits. A detecting unit detects resonance signals of the plurality of resonant circuits. A plate has therein the sending unit and detecting unit. A determining unit determines a part of the object placed on the plate, the part facing the predetermined direction, using differences of detected levels of the resonance signals of the plurality of resonant circuits of the object detected by the detecting unit.