The correct answer is A. D.C. shunt motor.
A D.C. shunt motor is a type of electric motor that uses direct current (DC) to power it. It is a brushed motor, which means that it has brushes that make contact with the commutator to switch the current to the different windings of the motor. The shunt winding is connected in parallel with the armature winding, which means that it receives the same amount of current as the armature winding. This makes the shunt motor a very stable motor, and it is often used in applications where a constant speed is required, such as in electric clocks.
A D.C. series motor is a type of electric motor that uses direct current (DC) to power it. It is a brushed motor, which means that it has brushes that make contact with the commutator to switch the current to the different windings of the motor. The series winding is connected in series with the armature winding, which means that it receives the same amount of current as the armature winding. This makes the series motor a very powerful motor, but it is also very unstable. The speed of the series motor is proportional to the current, so if the current changes, the speed of the motor will change as well. This makes the series motor unsuitable for applications where a constant speed is required.
An A.C. induction motor is a type of electric motor that uses alternating current (AC) to power it. It is an induction motor because the current in the rotor is induced by the magnetic field of the stator. The stator is the part of the motor that is stationary, and the rotor is the part of the motor that rotates. The stator has a number of windings that are arranged in slots around the stator. The rotor has a number of bars that are arranged around the rotor. The bars are not connected to each other, but they are connected to a set of slip rings. The slip rings are connected to a commutator, which is a device that switches the current to the different bars of the rotor.
An A.C. synchronous motor is a type of electric motor that uses alternating current (AC) to power it. It is a synchronous motor because the speed of the rotor is synchronized with the speed of the stator. The stator is the part of the motor that is stationary, and the rotor is the part of the motor that rotates. The stator has a number of windings that are arranged in slots around the stator. The rotor has a number of magnets that are arranged around the rotor. The magnets are arranged so that they are opposite to the poles of the stator windings. When the stator windings are energized, they create a magnetic field. The magnetic field of the stator interacts with the magnetic field of the rotor, and this causes the rotor to rotate.
In conclusion, the correct answer is A. D.C. shunt motor.