Q.1
Which of the following is used to connect the armature conductors to the commutator?
  • a) vee-ring
  • b) Equalizer ring
  • c) Banding
  • d) Risers
Q.2
What process takes place in an electric machine when stationary is kept in a time-varying field?
  • a) Energy conversion
  • b) Energy transference
  • c) Rotation of coil
  • d) Movement of coil
Q.3
Which of the following is the same as the transformer emf?
  • a) Pulsational emf
  • b) Induction emf
  • c) Interactional emf
  • d) Motional emf
Q.4
How will be the size and cost of a rotating electric machine that has a higher output coefficient be?
  • a) small size and more cost
  • b) small size and less cost
  • c) large size and more cost
  • d) large size and less cost
Q.5
How will high specific loading according to rotating electric machine affect the efficiency?
  • a) Efficiency increases
  • b) Efficiency decreases
  • c) Efficiency may increase or decrease
  • d) Efficiency is not affected
Q.6
What kind of layer winding in an electric machine occupies the whole slot by one coil side of the coil?
  • a) Single layer
  • b) Double layer
  • c) Single layer or Double layer
  • d) Mixture of single layer and double layer
Q.7
What are the different types of interpoles in DC electric machines?
  • a) Parallel sided and Tapered
  • b) Open and closed
  • c) Single layer and double layer
  • d) Armature and field
Q.8
What is the relation between hysteresis and the number of poles?
  • a) hysteresis loss decreases with an increase in number of poles
  • b) hysteresis loss increases with an increase in number of poles
  • c) hysteresis loss remains constant with an increase in number of poles
  • d) hysteresis loss may increase or decreases with an increase in number of poles
Q.9
Which of these will increase with an increase in the number of poles?
  • a) Weight of field copper
  • c) Overall diameter of machine
  • d) Weight of armature copper
Q.10
How should be the value of field mmf to prevent excessive distortion of field form by armature reaction in an electric machine?
  • a) large compared to armature mmf
  • b) small compared to armature mmf
  • c) zero
  • d) large or small compared to armature mmf
Q.11
Which of these windings are said to be bifurcated windings?
  • a) Whole coil winding
  • b) Semi-closed winding
  • c) half-coil winding
  • d) Hemitropic windings
Q.12
How will the length of the air gap in a DC electric machine affect pulsational loss in pole faces?
  • a) Pulsational loss increases with an increase in air gap length
  • b) Pulsational loss decreases with an increase in air gap length
  • c) Pulsational loss does not change with an increase in air gap length
  • d) Pulsational loss may increase or decrease with an increase in air gap length
Q.13
Which of these options are correct for a DC electric machine with a large air gap?
  • a) More pulsational loss in pole face
  • b) Quieter operation of the machine
  • c) Distorting effect of armature reaction more
  • d) No proper ventilation
Q.14
How should be the number of slots in a DC electric machine for better cooling of armature conductors?
  • a) Large number of slots
  • b) Less number of slots
  • c) Slots equal to the number of poles
  • d) Number of slots depends on commutation
Q.15
Which of the following circuit is made to insulate one conductor from another?
  • a) Electric circuit
  • b) Magnetic circuit
  • c) Dielectric circuit
  • d) Thermal circuit
Q.16
How is the saturation level of ferromagnetic materials determined in electrical machines?
  • a) Using maximum allowable flux density
  • b) Using specific permeance
  • c) Using the linear velocity of material
  • d) Using maximum allowable loss
Q.17
What part of electric machines will the temperature rise mainly affect?
  • a) Conductance of winding
  • b) Insulation of machine
  • c) Speed of machine
  • d) Torque of machine
Q.18
How is the size of insulation determined?
  • a) By maximum voltage stress and maximum saturation
  • b) By mechanical stress
  • c) By maximum saturation and mechanical stress
  • d) By maximum voltage stress and mechanical stress
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