Electrical Machines
The direction of rotation of a DC compound motor can be reversed by interchanging

 series field connections.
 armature connections.
 armature or field connections.
 shunt field connections.

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

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

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