A. 10°C
B. 20°C
C. 30°C
D. 45°C
Related Mcqs:
- The efficiency of the copper oxide rectifier seldom exceeds____________?
A. 90 to 95%
B. 85 to 90%
C. 80 to 85%
D. 65 to 75% - On which of the following factors the number of phases for which a rectifier should be designed depend ?
A. The voltage regulation of the rec¬tifier should be low
B. In the output circuit there should be no harmonics
C. The power factor of the system should be high
D. The rectifier supply transformer should be utilized to the best ad-vantage
E. all of the above - In a mercury arc rectifier, the anode is usually made of_____________?
A. copper
B. aluminium
C. silver
D. graphite
E. tungsten - A commutating rectifier consists of commutator driven by___________?
A. an induction motor
B. a synchronous motor
C. a D.C. series motor
D. a D.C. shunt motor - In a glass bulb mercury arc rectifier the maximum current rating is restricted to___________?
A. 2000 A
B. 1500 A
C. 1000 A
D. 500 A - The efficiency of an electrolytic rectifier is nearly____________?
A. 80%
B. 70%
C. 60%
D. 40% - If cathode and anode connections in a mercury arc rectifier are inter changed_____________?
A. the rectifier will not operate
B. internal losses will be reduced
C. both ion and electron streams will move in the same direction
D. the rectifier will operate at reduced efficiency - In a mercury pool rectifier, the voltage drop across its electrodes___________?
A. is directly proportional to load
B. is inversely proportional to load
C. varies exponentially with the load current
D. is almost independent of load current - The potential drop in the arc, in a mercury arc rectifier, varies_____________?
A. 0.05 V to 0.2 V per cm length of the arc
B. 0.5 V to 1.5 V per cm length of the arc
C. 2 V to 3.5 V per cm length of the arc
D. none of the above - In a mercury arc rectifier positive ions are attracted towards______________?
A. anode
B. cathode
C. shell bottom
D. mercury pool
