Rectifiers And Converters(Engineering > Electrical Engineering ) Questions and Answers
Question 1. In which of the following equipment direct current is needed?
Telephones
Relays
Time switches
All of the above
Explanation:-
Answer: Option D. -> All of the above
Question 2. Mercury, in arc rectifiers, is chosen for cathode because
Its ionization potential is relatively low
Its atomic weight is quite high
Its boiling point and specific heat are low
All of the above
Explanation:-
Answer: Option D. -> All of the above
Question 3. It is the_______of the transformer on which the magnitude of angle of overlap depends.
resistance
capacitance
leakage reactance
any of the above
Explanation:-
Answer: Option C. -> leakage reactance
Question 4. Normally, which of the following is used, when a large-scale conversion from AC. to D.C. power is required?
Motor-generator set
Motor converter
Rotary converter
Mercury arc rectifier
Explanation:-
Answer: Option D. -> Mercury arc rectifier
Question 5. Which of the following is the loss within the mercury arc rectifier chamber?
Voltage drop in arc
Voltage drop at the anode
Voltage drop at the cathode
All of the above
Explanation:-
Answer: Option D. -> All of the above
Question 6. The voltage drop at anode, in a mercury arc rectifier is due to
self restoring property of mercury
high ionization potential
energy spent in overcoming the electrostatic field
high temperature inside the rectifier
Explanation:-
Answer: Option C. -> energy spent in overcoming the electrostatic field
Question 7. A rotary converter is a single machine with
one armature and one field
two armatures and one field
one armature and two fields
none of the above
Explanation:-
Answer: Option A. -> one armature and one field
Question 8. The efficiency of an electrolytic rectifier is nearly
80%
70%
60%
40%
Explanation:-
Answer: Option C. -> 60%
Question 9. Which of the following mercury arc rectifier will deliver least undulating current?
Six-phase
Three-phase
Two-phase
Single-phase
Explanation:-
Answer: Option A. -> Six-phase
Question 10. In a grid control of mercury arc rectifiers when the grid is made positive relative to cathode, then it the electrons on their may to anode.