A rotary unit of this motor has a plurality of magnets, a hollow shaft which has a tubular shape, and a ball nut. Each of the magnets is in contact with an outer surface of the hollow shaft. The ball nut is disposed on a radially inner side of the hollow shaft. At least a portion of the magnets, at least a portion of the hollow shaft, and at least a portion of the ball nut overlap in a circumferential direction. The hollow shaft and the ball nut are made of a magnetic material. An inner circumferential surface of the hollow shaft and an outer circumferential surface of the ball nut are in contact with each other.