Electrical Machines
In dc machines, the field system has to be provided on stator unlike synchronous machines Where in it could be on any member, because

 commutator action is not possible otherwise
 it gives more uniform air-gap flux distribution
 it reduces field structure iron losses
 dc machines are comparatively low rating machines.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Torque angle of a synchorous machine operating from a constant voltage bus is usually defined as the space angle between

 Stator mmf wave and resultant mmf wave.
  Rotor mmf wave and stator mmf wave.
 Stator mmf wave and resultant flux density.
 Rotor mmf wave and resultant flux density wave.

ANSWER DOWNLOAD EXAMIANS APP
MORE MCQ ON Electrical Machines