The applications of selenium rectifiers are usually limited to potential of 100 V 30 V 20 V 10 V TRUE ANSWER : ? YOUR ANSWER : ?
The internal efficiency of a mercury arc rectifier depends on voltage and current r.m.s. value of current current only voltage only TRUE ANSWER : ? YOUR ANSWER : ?
The cathdde voltage drop, in a mercury arc rectifier, is due to expenditure of energy in overcoming the electrostatic field expenditure of energy in ionization expenditure of energy in liberating electrons from the mercury surface resistance TRUE ANSWER : ? YOUR ANSWER : ?
Selenium rectifier can be operated at temperatures as high as 25°C 40°C 60°C 75°C TRUE ANSWER : ? YOUR ANSWER : ?
A rotary converter operates at a high power factor None of the listed here zero power factor low power factor TRUE ANSWER : ? YOUR ANSWER : ?
In a mercury arc rectifier positive ions are attracted towards anode mercury pool cathode shell bottom TRUE ANSWER : ? YOUR ANSWER : ?
The potential drop in the arc, in a mercury arc rectifier, varies 0.05 V to 0.2 V per cm length of the arc 0.5 V to 1.5 V per cm length of the arc none of the listed here 2 V to 3.5 V per cm length of the arc TRUE ANSWER : ? YOUR ANSWER : ?
Normally, which of the following is used, when a large-scale conversion from AC. to D.C. power is required? Rotary converter Mercury arc rectifier Motor converter Motor-generator set TRUE ANSWER : ? YOUR ANSWER : ?
In phase-shift control method the control is carried out by varying the of grid voltage. phase polarity magnitude All of the listed here TRUE ANSWER : ? YOUR ANSWER : ?
In a rotary converter I2R losses as compared to a D.C. generator of the same size will be Remain same More None of the listed here Less TRUE ANSWER : ? YOUR ANSWER : ?