Electrical Machines
The mmf produced by rotor currents of a 3 - Φ induction motor

  is at standstill with respect to stator mmf.
  rotates at the speed of rotor in the air gap.
  rotates at synchronous speed with respect to rotor.
  rotates at slip speed with respect to stator mmf.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Flashing the field of DC generator means

  creating residual magnetism by a DC source.
  neutralising residual magnetism.
  making the magnetic losses forces parallel.
 increasing flux density by adding extra turns of winding.

ANSWER DOWNLOAD EXAMIANS APP