Electrical Machines
Which of following methods are suitable for the speed control of squirrel cage induction motor? 1. Voltage control. 2. Frequency control. 3. Pole changing method. 4. Rotor resistance control select the correct answer using the codes given below:-

 2, 3 and 4.
  1, 2 and 3.
 2 and 4.
 1, 3 and 4.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Which of the following represents the commutator pitch?

 Number of commutator segments between two successive coils.
 Number of conductors spanned by one coil at the back end of the armature.
 The distance between the staring of first coil and its next successive coil
 Number of conductors spanned by one coil at the front end of the armature.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
The residual magnetism of a self-excited dc generator is lost. To build up its emf again

 field winding must be excited by low voltage dc supply
 the field winding connection must be reversed
 the field winding must be replaced
 the armature connection must be reversed

ANSWER DOWNLOAD EXAMIANS APP
MORE MCQ ON Electrical Machines