A. 90 to 95%
B. 85 to 90%
C. 80 to 85%
D. 65 to 75%
Related Mcqs:
- Copper oxide rectifier is usually designed not to operate above___________?
A. 10°C
B. 20°C
C. 30°C
D. 45°C - The efficiency of an electrolytic rectifier is nearly____________?
A. 80%
B. 70%
C. 60%
D. 40% - The internal efficiency of a mercury arc rectifier depends on___________?
A. voltage only
B. current only
C. voltage and current
D. r.m.s. value of current
E. none of the above - The ignited or auxiliary anode in mercury arc rectifier is made of____________?
A. graphite
B. boron carbide
C. aluminium
D. copper - Selenium rectifier can be operated at temperatures as high as____________?
A. 25°C
B. 40°C
C. 60°C
D. 75°C - Which of the following mercury arc rectifier will deliver least undulating current?
A. Six-phase
B. Three-phase
C. Two-phase
D. Single-phase - When a rectifier is loaded which of the following voltage drops take place ?
A. Voltage drop in transformer reactance
B. Voltage drop in resistance of transformer and smoothing chokes
C. Arc voltage drop
D. All of the above - 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
