Principle of electric motor : Electric motor is based upon Fleming\’s left-hand rule. When a current carrying conductor capable of free movement is placed in a magnetic field, it experiences a mechanical force and begins to move in a direction given by Fleming\’s left-hand rule.Electric generator is based upon Fleming\’s right-hand rule.Fleming\’s right-hand rule: Stretch the thumb, fore-finger, control (middle) finger of right hand so that they are perpendicular to each other. If fore-finger indicates the direction of magnetic field, the thumb shows the direction of motion of the conductor, the central (middle) finger will show the direction of induced current.