Hi readers, this is another post about multiple choice questions on dc generators checkout and comment if you have doubts.
1) A homopolar generator usually has
A) high voltage and high current
B) low voltage and high current
C) low voltage and low current
D) high voltage and low current
Ans:B
2) In a dc machine
A) the current and emf in armature conductors are alternating while those at the terminals are unidirectional
B) the current and emf in armature conductors are unidirectional while those at the terminals are alternating
C) the current and emf in armature conductors and at the terminals are unidirectional
D) the emf in armature conductors and at the terminals are alternating while current there is unidirectional
Ans:A
3) The armature of dc machine is made of silicon steel lamination to
A) reduce hysteresis loss only
B) reduce eddy current loss only
C) increase the permeability
D) reduce both hysteresis loss and eddy current loss
Ans:D
4) Laminated Yoke in dc motor can reduce
A) speed regulation
B) iron loss
C) temperature rise
D) sparking on load.
Ans:B
5) In a dc machine, fractional pitch winding is employed to
A) increase generated voltage
B) reduce sparking
C) save copper
D) improve cooling
E) both (B) and (C)
Ans:E
6) Poles of dc machine often laminated to
A) reduce pulsation loss.
B) reduce armature reaction
C) reduce iron weight
D) dissipate more heat
Ans:A
7) Which of the following are the variable losses in a rotating machine?
A) Core loss and mechanical loss
B) Core loss and stray load loss
C) Copper loss and core loss
D) Copper loss and stray load loss
Ans:D
8) Number of tappings to each equalizer ring is equal to number of
A) poles
B) pole pairs
C) parallel paths
D) commutator segments.
Ans:B
9) In a dc generator, the ripples in the direct emf generated are reduced by employing
A) commutator with large number of segments
B) equalizer rings
C) carbon brushes
D) graphite brushes.
Ans:A
10) In a dc machine, the space waveform of the air-gap flux distribution affects
A) torque only
B) voltage only
C) both the torque and voltage
D) neither the torque nor the voltage
Ans:D
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1) A homopolar generator usually has
A) high voltage and high current
B) low voltage and high current
C) low voltage and low current
D) high voltage and low current
Ans:B
2) In a dc machine
A) the current and emf in armature conductors are alternating while those at the terminals are unidirectional
B) the current and emf in armature conductors are unidirectional while those at the terminals are alternating
C) the current and emf in armature conductors and at the terminals are unidirectional
D) the emf in armature conductors and at the terminals are alternating while current there is unidirectional
Ans:A
3) The armature of dc machine is made of silicon steel lamination to
A) reduce hysteresis loss only
B) reduce eddy current loss only
C) increase the permeability
D) reduce both hysteresis loss and eddy current loss
Ans:D
4) Laminated Yoke in dc motor can reduce
A) speed regulation
B) iron loss
C) temperature rise
D) sparking on load.
Ans:B
5) In a dc machine, fractional pitch winding is employed to
A) increase generated voltage
B) reduce sparking
C) save copper
D) improve cooling
E) both (B) and (C)
Ans:E
6) Poles of dc machine often laminated to
A) reduce pulsation loss.
B) reduce armature reaction
C) reduce iron weight
D) dissipate more heat
Ans:A
7) Which of the following are the variable losses in a rotating machine?
A) Core loss and mechanical loss
B) Core loss and stray load loss
C) Copper loss and core loss
D) Copper loss and stray load loss
Ans:D
8) Number of tappings to each equalizer ring is equal to number of
A) poles
B) pole pairs
C) parallel paths
D) commutator segments.
Ans:B
9) In a dc generator, the ripples in the direct emf generated are reduced by employing
A) commutator with large number of segments
B) equalizer rings
C) carbon brushes
D) graphite brushes.
Ans:A
10) In a dc machine, the space waveform of the air-gap flux distribution affects
A) torque only
B) voltage only
C) both the torque and voltage
D) neither the torque nor the voltage
Ans:D
if you like my post please share and don't forget to subscribe.
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