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

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

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
In a stepper motor the detente torque means

  maximum of the static torque with the phase winding unexcited.
  minimum of the static torque with the phase winding excited.
  maximum of the static torque with the phase winding excited.
  minimum of the static torque with the phase winding unexcited.

ANSWER DOWNLOAD EXAMIANS APP