Which of these statements about inducing current in ac and dc motors are true? 1. in an ac induction motor current in the stator is conducted from an external line voltage 2. in an ac induction motor current in the rotor is conducted from an external line voltage 3. in a dc motor current in the armature is conducted from an external line voltage 4. in a dc motor current in the field windings is conducted from an external line voltage

Option 2.

Explanation:

In an induction motor the flow of current in the rotor is not conducted by any DC source but by AC source through an external line voltage.

This happens because in an induction motor the 3 phase supply is given to the stator and the rotor is connected to DC source and as the result of the armature reaction, i.e., when the rotor magnetic field caused by rotor conductor cuts the stator magnetic field, a current is induced in the rotor.

Thus the conduction of current in the rotor is the result of an external line voltage.  

the correct answer is c.stops after infancy and childhood.

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