The present disclosure proposes a resonant motor that has a control unit for driving the resonant motor at a driving frequency a measurement unit for measuring at a predetermined first time instant a first motor signal that is indicative of whether the effective resonance frequency of the resonant motor is above or below a predetermined first resonance frequency value and an evaluation unit for evaluating the measured first motor signal and for determining whether the effective resonance frequency has changed from being above to below or from being below to above the predetermined first resonance frequency value. An electric device comprising such a resonant motor is also described.
