The correct answer is: A. Universal motor.
A universal motor is a type of electric motor that can run on both alternating current (AC) and direct current (DC). It is a single-phase motor that uses a squirrel-cage rotor. The stator of a universal motor has two windings: a main winding and a field winding. The main winding is connected to the power source, and the field winding is connected to a commutator. The commutator is a rotating switch that reverses the polarity of the field winding every time the rotor turns halfway around. This reversal of polarity keeps the magnetic field of the stator aligned with the magnetic field of the rotor, which allows the motor to run on either AC or DC.
Repulsion motors, synchronous motors, and reluctance motors can only run on AC.
A repulsion motor is a type of electric motor that uses a squirrel-cage rotor. The stator of a repulsion motor has two windings: a main winding and a field winding. The main winding is connected to the power source, and the field winding is not connected to anything. The magnetic field of the stator induces a current in the rotor, which creates its own magnetic field. The interaction of the stator and rotor magnetic fields causes the rotor to turn.
A synchronous motor is a type of electric motor that runs at a constant speed, regardless of the load. The stator of a synchronous motor has two windings: a main winding and a field winding. The main winding is connected to the power source, and the field winding is connected to a DC power source. The magnetic field of the stator induces a current in the rotor, which creates its own magnetic field. The interaction of the stator and rotor magnetic fields causes the rotor to turn at the same speed as the magnetic field of the stator.
A reluctance motor is a type of electric motor that uses a reluctance rotor. The stator of a reluctance motor has two windings: a main winding and a field winding. The main winding is connected to the power source, and the field winding is not connected to anything. The magnetic field of the stator induces a current in the rotor, which creates its own magnetic field. The interaction of the stator and rotor magnetic fields causes the rotor to turn.